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1

Bertolucci, Maria Paula Barchi [UNESP]. "O tipo de mesohabitat (corredeira e remanso) e a complexidade do substrato afetam a fauna de macroinvertebrados aquáticos de riacho." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/99453.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Os diferentes tipos de mesohabitat e a complexidade do substrato podem ser um importante fator na determinação da riqueza, abundância e distribuição das comunidades bentônicas. Neste sentido, no presente trabalhos fizemos um experimento em um riacho do Parque Estadual Intervales, Estado de São Paulo, com o objetivo de responder as seguintes questões: 1) a abundância, riqueza e composição da fauna de macroinvertebrados aquáticos são afetadas pelo tipo de mesohabitat (corredeira e remanso)? 2) a abundância, riqueza e composição da fauna são afetadas por substratos com diferentes complexidades fractais? 3) A fauna é afetada pela interação entre o tipo de mesohabitat e a complexidade do substrato? Para responder esses questionamentos, coletamos dados experimentais em um riacho de Mata Atlântica do Sudeste do Brasil. Foram coletados 2.223 indivíduos. O primeiro eixo da DCA explicou 48,5% da variabilidade e separou a fauna coletada em remanso daquela coletada em corredeira. O segundo eixo explicou 15,9% e não pôde ser interpretado. A DCA não mostrou nenhum padrão que pudesse ser explicado pelas diferentes dimensões fractais. A maior abundância dos macroinvertebrados aquáticos foi observada em corredeiras. O tipo de mesohabitat e a complexidade do substrato não afetaram a riqueza padronizada. Por outro lado, o tipo de mesohabitat afetou significativamente a composição faunística, DCA I
The richness, abundance and distribution of benthic communities may be affected by the different types of mesohabitat and by substrate complexity. In this sense, in the present work, we made a experiment in a stream located in the Intervales State Park, São Paulo State, with the aim to answer the following questions: 1) are abundance, richness and the faunal composition of aquatic macroinvertebrates affected by the type of mesohabitat (riffle and pool)? 2) Are abundance, richness and the faunal composition affected by the substrates with different fractal complexity? 3) Does the interaction between mesohabitat type and substrate complexity affect the fauna? To answer these questions, we collected experimental data in an Atlantic Rainforest stream in the Southeastern of Brazil. We collected 2.223 individuals. The first axis of DCA explained 48.5% of the variability and segregated the fauna of riffle from that of pool. The second axis explained 15,9% and could not be interpreted. The DCA analyses did not show any pattern that could be explained by the different fractal dimensions. The greatest aquatic macroinvertebrate abundance was observed in riffles. The mesohabitat type and the substrates complexity did not affect the standardized richness. On the other hand, the mesohabitat type affected significantly the faunal composition, DCA I
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2

Bertolucci, Maria Paula Barchi. "O tipo de mesohabitat (corredeira e remanso) e a complexidade do substrato afetam a fauna de macroinvertebrados aquáticos de riacho /." Botucatu : [s.n.], 2012. http://hdl.handle.net/11449/99453.

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Orientador: Ricardo Cardoso Benine
Banca: Virginia Sanches Uieda
Banca: Alaide Aparecida Fonseca Gessner
Resumo: Os diferentes tipos de mesohabitat e a complexidade do substrato podem ser um importante fator na determinação da riqueza, abundância e distribuição das comunidades bentônicas. Neste sentido, no presente trabalhos fizemos um experimento em um riacho do Parque Estadual Intervales, Estado de São Paulo, com o objetivo de responder as seguintes questões: 1) a abundância, riqueza e composição da fauna de macroinvertebrados aquáticos são afetadas pelo tipo de mesohabitat (corredeira e remanso)? 2) a abundância, riqueza e composição da fauna são afetadas por substratos com diferentes complexidades fractais? 3) A fauna é afetada pela interação entre o tipo de mesohabitat e a complexidade do substrato? Para responder esses questionamentos, coletamos dados experimentais em um riacho de Mata Atlântica do Sudeste do Brasil. Foram coletados 2.223 indivíduos. O primeiro eixo da DCA explicou 48,5% da variabilidade e separou a fauna coletada em remanso daquela coletada em corredeira. O segundo eixo explicou 15,9% e não pôde ser interpretado. A DCA não mostrou nenhum padrão que pudesse ser explicado pelas diferentes dimensões fractais. A maior abundância dos macroinvertebrados aquáticos foi observada em corredeiras. O tipo de mesohabitat e a complexidade do substrato não afetaram a riqueza padronizada. Por outro lado, o tipo de mesohabitat afetou significativamente a composição faunística, DCA I
Abstract: The richness, abundance and distribution of benthic communities may be affected by the different types of mesohabitat and by substrate complexity. In this sense, in the present work, we made a experiment in a stream located in the Intervales State Park, São Paulo State, with the aim to answer the following questions: 1) are abundance, richness and the faunal composition of aquatic macroinvertebrates affected by the type of mesohabitat (riffle and pool)? 2) Are abundance, richness and the faunal composition affected by the substrates with different fractal complexity? 3) Does the interaction between mesohabitat type and substrate complexity affect the fauna? To answer these questions, we collected experimental data in an Atlantic Rainforest stream in the Southeastern of Brazil. We collected 2.223 individuals. The first axis of DCA explained 48.5% of the variability and segregated the fauna of riffle from that of pool. The second axis explained 15,9% and could not be interpreted. The DCA analyses did not show any pattern that could be explained by the different fractal dimensions. The greatest aquatic macroinvertebrate abundance was observed in riffles. The mesohabitat type and the substrates complexity did not affect the standardized richness. On the other hand, the mesohabitat type affected significantly the faunal composition, DCA I
Mestre
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3

Arendse, Clement J. "Aspects of the early life history and a per-recruit assessment of white stumpnose Rhabdosargus globiceps (Pisces: Sparidae) in Saldanha Bay with recommendations for future research and monitoring." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/10069.

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This study focuses on several aspects of the life history of R. globiceps, and includes a study of juvenile habitat, a hatch date analysis, methods to increase precision of age estimates obtained from reading otoliths and a per-recruit assessment.
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4

Alva, Julia Sandoval. "Thermal Ecology of Urosaurus ornatus (Ornate Tree Lizard), in the Northern Chihuahuan Desert on Indio Mountains Research Station, Texas." Thesis, The University of Texas at El Paso, 2014. http://pqdtopen.proquest.com/#viewpdf?dispub=1564658.

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The main goal of this study was to determine the thermal ecology of the small tree lizard Urosaurus ornatus in a Chihuahuan Desert landscape. The study site was located at Indio Mountains Research Station (IMRS), Hudspeth County, Texas. We obtained body temperature (Tb) data on 385 lizards collected from April 2007 to June 2014 during the active period using a cloacal thermometer. Additionally, we recorded air temperature (Ta) and substrate temperature (Ts) of lizard microhabitats at the time of capture, and the operative temperature of lizard models left in the sun and shade from May to September 2014. My results showed that the mean Tb for all adult lizards was 33.6 ± 2.8°C, with a range of 24.0 to 40.2°C. This average Tb was similar but lower than those found in other populations in Southwestern United States. The results indicated that U. ornatus at IMRS displays mostly a thigmothermic behavior. Thermoregulatory behavior of these individuals showed that U. ornatus is a thermoconformer on IMRS. There was no statistical difference in mean Tb between males and females or between non-gravid females. However, there was a significant difference between lizards found in the sun and lizards found in the shade. It is expected that rising global temperatures will influence this region and therefore will have an impact on the population of U. ornatus too; possibly affecting aspects such as time for feeding, reproducing, and of course thermoregulating. Thus, it is important for us to understand the thermoregulatory needs of ectothermic organisms as they are dependent on the direct environmental temperatures for survival, especially since many recognize that rapid global warming has already been activated by human misuse of natural resources.

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5

McClelland, Gregory T. W. "Ecology of the Black-faced sheathbill on Marion Island." Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/85617.

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Thesis (PhD)--Stellenbosch University, 2013.
ENGLISH ABSTRACT: As the pace of climate change has begun to accelerate so too has it become clear that the direct impacts thereof are likely to have profound consequences for many island systems. Moreover, it has also been suggested that climate change will exacerbate the effects of many invasive species, so further impacting both diversity and ecosystem functioning. Forecasts for such interactions have been most pronounced for the Southern Ocean islands, which are home to a wide variety of endemic species. This thesis is about such interactions and their specific impacts on a key endemic, the black-faced sheathbill (Chionis minor) on the Prince Edward Islands. Of increasing concern is how invasive rodent populations in the Southern Ocean may be responding to global climate change, as ameliorating conditions on these islands are forecast to decrease thermal and resource restrictions on rodents. However, firm evidence for changing rodent populations in response to climate change, and demonstrations of associated impacts on the terrestrial environment, are entirely absent for the region. In Chapter 2 of this thesis, these relationships are explored for invasive house mice (Mus musculus) on Marion Island. Using spatially explicit capture-recapture modeling, it is determined that mouse populations across a range of habitats have increased over time. Owing to an extended breeding season, made possible by ameliorating conditions brought on by climate change, the total number of mice on the island at annual peak density more than doubled over the past decade. It is also demonstrated that mice directly reduce invertebrate densities, with biomass losses up to two orders of magnitude in some habitats. Because of the importance of invertebrates to nutrient cycling on the island, such changes are likely to have significant ecosystem-level impacts. In Chapter 3 the focus expands to examine how increasing mouse impacts and other outcomes of climate change are affecting the ecology of the black-faced sheathbill. It has been established that invasive house mice are capable of suppressing the populations of several seabird species in the Southern Ocean. However, mouse impacts on the region’s few island endemic land-birds remain largely unexplored. Further, a significant effect of climate change may be realized by altering interspecific interactions, specifically food webs. A significant portion of sheathbill diets is derived from rockhopper penguins, a species currently under a climate-change-driven decline, which may have significant effects on sheathbills. The study found that terrestrial invertebrates are no longer a significant prey resource for sheathbills on Marion Island, and that sheathbills have effectively been displaced from a formerly important winter food resource by mice. In response, the number of sheathbills foraging in king penguin colonies increased. Moreover, a reduced rockhopper penguin population lead to significant declines in both the number and proportion of sheathbills foraging in rockhopper penguin colonies. The sum result was a significant decline in the body condition of female sheathbills. Rather than decrease reproductive output, sheathbills responded by decreasing clutch size and producing significantly fewer male nestlings. While population estimates did not detect a reduction in the number of sheathbills, population projections suggest that the population is in decline, with the reproductive population declining faster than the absolute population. There is need for greater study of island species, as for even relatively well-studied taxa such as birds many aspects of ecology remain significantly less studied when compared to species occurring on continents. For example, basal metabolic rate (BMR) is a fundamental characteristic of all endotherms, yet only a handful of island birds have had their BMR measured, and fewer still to a level that allows intraspecific analysis. In Chapter 4 the BMR of black-faced sheathbills on Marion Island was measured to determine whether the unique phylogenetic position and ecology of sheathbills equate to a unique BMR when allometrically compared to other birds. It was found that the BMR of sheathbills is typical for a bird of its size. However, significant intraspecific variation was found to occur, with differences in habitat quality a likely driver. The results of the study show that the combined effects of climate change and invasive species can have significant consequences for terrestrial endemics in the Southern Ocean. Further, the long-term changes observed in sheathbills make clear the need for improved documentation and study of island species in general, as many of the responses observed in this study are significant but subtle and would not have been evident without detailed knowledge of species ecology and vital rates. Giving greater focus to insular biota is imperative to understanding their current status and ecology as well as establishing a barometer against which further global change can be measured and mitigation measures evaluated. Specific conservation responses for the black-faced sheathbill on Marion Island include the provision of nest boxes at king penguin colonies, and eradication of house mice. The latter would have long-term benefits for the species, invertebrates, ecosystem functioning generally, and likely also for important seabirds such as several species of albatrosses whose chicks are being increasingly preyed on by mice. Eradication would, however, be difficult and expensive, and with substantial potential non-target effects, including on sheathbills, that would have to be carefully managed. In the absence of local mouse eradication, and with ongoing climate change, specific management of the sheathbill population through the provision of supplementary nesting sites seems the most appropriate conservation action. It should therefore be examined in small-scale trials to ascertain the likelihood of unintended consequences. Importantly, the maintenance of Prince Edward Island as largely free of invasive species is key to the conservation of the local black-faced sheathbill subspecies, Chionis minor marionensis, endemic to the Prince Edward Island group.
AFRIKAANSE OPSOMMING: Soos die tempo van klimaatsverandering begin om te versnel, het dit ook duidelik geword dat die direkte impak daarvan waarskynlik ernstige gevolge vir baie eilande gaan hê. Verder word dit is ook voorgestel dat klimaatsverandering die gevolge van baie indringerspesies sal vererger, so ʼn verdere impak het op beide diversiteit en die funksionering van die ekosisteem. Voorspellings vir sulke interaksies is die meeste uitgespreek vir die Suidelike Oseaan-eilande, wat ook die tuiste van 'n wye verskeidenheid van endemiese spesies is. Hierdie tesis is oor sulke interaksies en hul spesifieke impak op 'n sleutel endemiese spesie is, die swart gesig skedebek (Chionis minor) op die Prince Edward-eilande. ʼn Groter bron van bekommernis is hoe uitheemse knaagdier bevolkings in die Suidelike Oseaan kan reageer teenoor globale klimaatsverandering, aangesien toestande op die eilande voorspel word om hitte en hulpbron beperkings vir knaagdiere te verminder. Maar, ferm bewyse vir die verandering van knaagdier bevolkings in reaksie op klimaatsverandering, en demonstrasies van gepaardgaande impakte op die terrestriële omgewing, is heeltemal afwesig vir die streek. In Hoofstuk 2 van hierdie tesis, word hierdie verhoudings ondersoek vir indringende huis muise (Mus musculus) op Marion-eiland. Ruimtelik vang-terugvang modelle word gebruik om vas te stel dat die muis bevolkings oor 'n verskeidenheid van habitatte mettertyd toegeneem het. As gevolg van 'n uitgebreide broeiseisoen as gevolg van die verligting van toestande gebring deur klimaatsverandering, het die totale aantal muise op die eiland by die jaarlikse hoogtepunt digtheid meer as verdubbel oor die afgelope dekade. Dit is ook getoon dat muise die digtheid van ongewerweldes direk verminder het, met biomassa verliese tot twee ordes in sommige habitatte. As gevolg van die belangrikheid van die ongewerweldes vir voedingstof sirkulering op die eiland, behoort sulke veranderinge waarskynlik 'n beduidende ekosisteem-vlak impak te hê. In Hoofstuk 3 word die fokus verbreed om te sien hoe die verhoging van die muis impakte en ander uitkomste van klimaatsverandering die ekologie van die swart gesig skedebek beïnvloed. Daar is vasgestel dat indringende huis muise in staat is om die bevolkings van verskeie spesies seevoëls te onderdruk in die Suidelike Oseaan. Maar die muis impak op die streek se paar eiland endemiese land voëls bly grootliks onverken. Verder kan 'n beduidende uitwerking van klimaatsverandering verwesenlik word deur die wysiging van interspesifieke interaksies, veral voedselwebbe. 'n Beduidende gedeelte van skedebek dieet word gekry van Geelkuifpikkewyne, 'n spesie wat tans onder 'n klimaat-veranderinggedrewe agteruitgang is, wat ook 'n beduidende uitwerking het op die skedebek. Die studie het gevind dat terrestriële ongewerweldes nie meer 'n beduidende prooi hulpbron vir die skedebek op Marion-eiland is nie, en dat die skedebek effektief is verplaas uit 'n voorheen belangrike winter kos hulpbron deur muise. In reaksie hierop het die aantal skedebekke wat kos soek in die koning pikkewyn kolonies toegeneem. Verder, 'n verlaagde Geelkuifpikkewyn bevolking lei tot 'n beduidende afname in beide die aantal en persentasie van skedebekke wat kos soek in Geelkuifpikkewyn kolonies. Die gevolg was 'n beduidende afname in die liggaamstoestand van die vroulike skedebekke. Eerder as ʼn afname van reproduksie, het skedebekke gereageer deur 'n vermindering in die aantal eiers en produseer aansienlik minder manlike kuikens. Terwyl bevolking skattings nie 'n afname in die aantal skedebekke kan vind nie, dui bevolking projeksies daarop dat die bevolking besig is om af te neem, met die voortplanting bevolking wat vinniger daal as die absolute bevolking. Daar is 'n behoefte vir 'n groter studie van eiland spesies, omdat selfs vir betreklik goed bestudeerde groepe soos voëls baie aspekte van die ekologie aansienlik minder bestudeer bly in vergelyking met spesies op die vastelande. Byvoorbeeld, basale metaboliese tempo (BMT) is 'n fundamentele kenmerk van alle endotermiese diere, maar net 'n handjievol van die eiland voëls het hul BMT laat meet, en nog minder tot 'n vlak wat dit moontlik maak intraspesifieke analise. In Hoofstuk 4 was die BMT van die swart gesig skedebek op Marion-eiland gemeet om te bepaal of die unieke filogenetiese posisie en ekologie van skedebekke gelyk aan 'n unieke BMT wanneer allometries vergelyk word met ander voëls. Daar is gevind dat die BMT van skedebekke tipies is vir 'n voël van sy grootte. Daar is egter belangrike intraspesifieke variasie gevind, met verskille in habitat kwaliteit as 'n waarskynlike verduideliking. Die resultate van die studie toon dat die gekombineerde effek van klimaatsverandering en indringerspesies beduidende gevolge vir terrestriele inheemse spesies in die Suidelike Oseaan kan hê. Verder maak die lang-termyn veranderinge waargeneem in skedebekke dit duidelik dat die behoefte aan verbeterde dokumentasie en studie van die eiland spesies in die algemeen, omdat baie van die reaksies waargeneem in hierdie studie betekenisvol is, maar subtiel en sou nie gewees het sonder gedetailleerde kennis van die spesies ekologie van die spesie nie. Om ʼn groter fokus op die insulêre biota te plaas is noodsaaklik om hul huidige status en die ekologie te begryp, sowel as om 'n barometer waarteen verdere globale verandering gemeet kan word en versagtende maatreëls geëvalueer. Spesifieke bewaring antwoorde vir die swart gesig skedebek op Marion-eiland sluit in die voorsiening van nes bokse by koning pikkewyne, en die uitwissing van huis muise. Laasgenoemde sou lang-termyn voordele vir die spesie en ongewerweldes hê, asook funksionering van die ekosisteem in die algemeen, en waarskynlik ook vir belangrike seevoëls soos verskeie spesies van albatrosse wie se kuikens toenemend geëet word deur muise. Uitwissing sou egter moeilik en duur wees, en het 'n aansienlike potensiaal vir nieteiken effekte, insluitend op skedebekke, wat sal versigtig moet bestuur word. In die afwesigheid van plaaslike muis uitwissing, en met voortdurende verandering van die klimaat, spesifieke bestuur van die skedebek bevolking deur die voorsiening van aanvullende broeiplekke blyk die mees geskikte bewaringsaksie. Dit moet dus ondersoek word in 'n kleinskaal proewe om die waarskynlikheid van onbedoelde gevolge te bepaal. Wat belangrik is die instandhouding van Prince Edward Eiland as grootliks vry van indringerspesies en is die sleutel tot die bewaring van die plaaslike swart gesig skedebek subspesie, Chionis minor marionensis, endemies aan die Prince Edward Eiland groep.
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Paulin, M. G. (Michael Geoffrey). "A mathematical and comparative study on cerebellar control of vestibular reflexes." Thesis, University of Auckland, 1985. http://hdl.handle.net/2292/2041.

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The first aim of this thesis is an introduction to some basic aspects of multivariate control theory which are relevant to the question of how the brain controls movements. A regulator is a device which forces a system to follow a specified trajectory in the presence of perturbations which might cause it to diverge from that trajectory. Regulation involves constructing an additional control input which depends upon the difference between the actual system state and the desired state. This requires the construction of a state estimate from raw data about system input and output. For effective state estimation, the sensor input gain to the state estimator needs to be time-varying. Under certain assumptions, the appropriate input gain can be specified analytically. The feedback regulation signal can then be constructed as a function of the state estimate. For effective regulation, the gain of the feedback function has to vary during maneuvers. Under certain assumptions an appropriate feedback gain can be specified analytically. The state observer input gain equations have a simple relationship to the feedback gain equations, so that gain specification is essentially the same task in each case. Cerebellar research has been dominated for the past 25 years by the theories of James Albus and David Marr. These mathematicians proposed similar models in which certain synapses in the cerebellar cortex are continuously modified by experience in such a way that movements which are consistently repeated under a given set of circumstances come to be performed automatically by the cerebellum. Much experimental work has focussed on the role of the vestibulo-cerebellum in fine control and learning of the vestibulo-ocular reflex. The state of the art along this line is formally described by Fujita's adaptive filter model of the cerebellar cortex. In chapter 4 it is shown that a basic feature of Fujita's model is inconsistent with available evidence. The 'Tensorial theory of brain function' is discussed in chapter 5. This is a novel theory of brain function which has been used in an attempt two explain cerebellar function. The attempt is a failure, based on sophistocated misconceptions and flawed by poor reasoning and clumsy analysis. The approach serves to confuse rather than clarify the question of cerebellar function. The final chapter of the first part of the thesis presents a basis for a new approach to cerebellar function based on the engineering theory of control of multivariate dynamical systems. It is proposed that the cerebellum is involved in movement regulation by controlling the gains of brainstem motor pathways, and in mapping the animal's environment by controlling the gains of sensory inputs to the midbrain. While learning undoubtedly does occur in the cerebellar cortex, this is not specifically a 'learning device', as commonly conceived. The second part of the thesis is concerned with the development and application of a method of system identification for characterising the dynamics of the vestibulo-ocular reflex and its components in an elasmobranch. The chosen method involves pulse-rate modulated bilateral electrical stimulation of the horizontal semicircular canal ampullary nerves. This produces a synthetic vestibulo-ocular reflex in a stationary preparation. The stimulus pattern is a pseudorandom binary sequence of pulse rates, so that cross-correlation of the stimulus pattern with the response signal gives a Unit Impulse Response dynamic signature for the system. Computer software for signal generation, recording, analysis and display was written by the author. The identification system was applied first to characterise the dynamics of the eye movement response to horizontal canal ampullary nerve stimulation, and compare this to the dynamics of the eye motor plant alone. The eye motor preparation acts as a first order low-pass filter with a time constant of about 0.2 seconds (16°C), while the ampullary preparation acts as a second order low-pass filter with a dominant time constant of about 0.75 seconds (16°C). Central pathways of the elasmobranch vestibulo-ocular reflex extend the time constant of the motor plant by a factor of 3-4, as in other animals. Eye movements predicted by fitted linear models accurately mimic eye movements recorded during experiments, suggesting both that central pathways of the reflex operate normally during this somewhat un-naturally evoked response and that the identification procedure is effective. Furthermore, combination of the ampullary nerve to eye movement transfer function obtained in this study, with head rotation to ampullary nerve transfer functions obtained by other workers, gives a consistent picture of elasmobranch vestibulo-ocular reflex function predicting compensatory eye movements in the band 0.2 - 4.0 Hz., and perhaps higher. The identification method has also been applied to produce models of vestibulocerebellar Purkinje cell dynamics during electrically evoked vestibular eye movements. Linear identification gives a poor characterisation of Purkinje cell activity during the high frequency vestibulo-ocular reflex. This is incompatible with linear phase-compensator models of the cerebellar cortex, but consistent with the reflex gain modulation theory of cerebellar function advocated in the first part of the thesis.
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Millar, Craig D. (Craig Donald). "A molecular and evolutionary study of skua breeding systems." Thesis, University of Auckland, 1993. http://hdl.handle.net/2292/2269.

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The skua (Family Stercorariidae) are a group of large, gull-like, predatory seabirds. Two skua species are found in the Antarctic region; the south polar skua (Catharacta maccormicki) and the brown skua (C. lonnbergi). The breeding distribution of the former, is restricted to the Antarctic continent and nearby islands, while the latter has a circumpolar distribution which extends northward from the Antarctic Peninsula and includes many of the Southern Ocean islands. The south polar skua is strictly monogamous, while in contrast, a number of populations of brown skua are comprised in part of communally breeding groups. The brown skua represents the only known example of a communally breeding seabird. In every skua species, breeding females are on average larger and heavier than males. However, in most skua species this dimorphism is relatively small and is of only limited use in sexing individuals. The discovery of sex-specific fragments in the DNA fingerprints of the south polar skua is reported. The multilocus probe pV47-2 hybridised to Hae III restriction fragments which were present exclusively in females and therefore presumably W-linked. The presence of these sex-specific fragments were used to identify female adults and chicks. In addition, the use of these fragments as potentially informative maternal markers is discussed. The parentage of the 13 families from two populations from Ross Island, Antarctica, determined by DNA fingerprinting, revealed a single instance of extra-pair paternity and a single instance of a chick which was parented by neither resident adult. The most likely explanation for the latter is the 'adoption' of a chick from a neighbouring territory. Similarly, DNA fingerprinting was used to assign the sex of individuals of brown skua from a population which breeds on the Chatham Islands, New Zealand. A large proportion of the Chatham Islands population breed in communal groups. Each communal group was shown to be comprised of a single female and two or more males. Consequently, the overall sex ratio amongst breeding birds was biased, with almost twice the number of males as females. In contrast the sex ratio amongst fledgling chicks did not differ significantly from 1:1. The patterns of reproductive success in breeding pairs and communal groups of the brown skua from the Chatham Islands population were determined using multilocus DNA fingerprinting. Sixteen breeding groups were examined, the parentage of 45 chicks produced over three breeding seasons was established using the probes 33.15 and 33.6. No evidence was found of either extra-pair paternity or extra-group fertilisation and there was no evidence of egg dumping by females in any breeding group. These results suggest that long-term banding records for breeding pairs and communal groups accurately reflect the overall reproductive success of these individual groups. In addition, preliminary band sharing analysis indicated that adult members of communal groups were not closely related. These findings are also supported by banding records and are in contrast to the findings of the majority of communally breeding species studied. In the 10 communally breeding groups examined, multiple paternity within a clutch was recorded on two of the 12 occasions in which two chicks were reared. Furthermore, analysis of parentage of the chicks belonging to communal groups in which the adults had remained unchanged for two or more seasons showed that some males had variable reproductive success in different seasons. These records suggest that estimates of reproductive success of individuals based on a single season's data can be misleading. Should temporal changes in paternity (and/or maternity) be shown to be common phenomena in other species, this would have major implications for the interpretation of many parentage studies. The explanation of altruistic behaviour is one of the central issues in contemporary evolutionary theory and behavioural ecology. One of the best known examples of apparent altruism is the helping behaviour which occurs in communal breeding groups such as those found in the brown skua. Within these groups individuals often help to raise offspring which are not their own. This behaviour is an apparent enigma in a world in which organisms are assumed to act in a selfish manner. Consequently, this behaviour has become a focal example at the centre of much evolutionary debate. A variety of theories have been suggested to explain helping behaviour, the most recent is that helping is an unselected consequence of the evolution of communal breeding. This hypothesis is discussed in relation to the recent literature and it is concluded that it does little to advance the current debate. An alternative theoretical approach to helping behaviour is outlined. In conclusion the general findings from the investigation of communal breeding in the brown skua are summarised and these findings are discussed. Finally, possible areas of future research are outlined.
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8

Stevens, Peter M. (Peter Michael). "Host races and cryptic species in marine symbionts." Thesis, University of Auckland, 1990. http://hdl.handle.net/2292/2321.

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The Pinnotheridae is a family of decapod crustaceans comprising more than 120 mostly microphagous and commensal species. As symbionts of a variety of aquatic invertebrates, pinnotherids typically live in an intimate association with their host depending on it for an almost lifelong source of nourishment and shelter, together with a site for mating. The New Zealand pinnotherid fauna was thought to comprise only one species, Pinnotheres novaezelandiae Filhol, associated with a multitude of hosts. Recently, however, a separate species, P. atrinicola Page, has been described which is regarded as being host specific to the horse mussel Atrina zelandica Gray. In this context, the relationship between pea crabs and their hosts is of special interest, and is the focus of this thesis. An investigation into the population dynamics of the symbiotic relationship between P novaezelandiae and its host, the green-lip mussel Perna canaliculus, at Westmere Reef, Auckland between May 1986 and July 1988 is reported. Ovigerous females and Stage I males and females were found throughout the sampling period, indicating that reproduction is continuous in this species. The developmental composition of the pea crab population reveals that soft-shelled males, usually regarded as an anomalous instar, formed a significant component of the pea crab population at all times. It is suggested that these individuals represent a distinct facies, analogous to the Stage II female instar. The presence of a pea crab was found to have a highly significant detrimental effect on mussel condition. Analysis of the distribution of pea crabs among the mussel population indicates mature crabs display a repulsed distribution favouring to live a solitary existence, whereas younger (pre-hard and Stage I) crabs showed a random distribution in broad agreement with a theoretical Poisson distribution. The biological status of the two described taxa was investigated by a survey of electrophoretically detectable genetic variation of populations from throughout the North Island of New Zealand. Pea crabs from 18 host populations from nine geographically disparate localities were subjected to cellulose acetate and poly-acrylamide electrophoresis. Forty-one enzyme systems were screened for polymorphism. Clearly resolved enzyme phenotypes were obtained at 23 presumptive loci, of which l5 exhibited polymorphism. An analysis of electromorph frequency data revealed that both taxa are highly genetically structured and typified by high levels of polymorphism and heterozygosity; results atypical of brachyuran crabs. P- atrinicola was found to exhibit strong patterns of geographic differentiation and clinal variation in electromorph frequency. Of particular significance is the pattern of genetic differentiation observed among populations of p. novaezelandiae. Hierarchical F-statistics indicated that the preponderance of inter-population differentiation can be attributed to differences in electromorph frequency among host-associated populations of P. novaezelandiae within a sampling locality. Geographic differentiation was a comparatively insignificant factor in the structuring of the sampled P. novaezelandiae populations. Individuals belonging to two genetically very distinct units were found within a newly recorded host species, Mactra ovata ovata Gray at Green and Wood Bays, Manukau Harbour. Hardy-Weinberg analyses indicate the host-associated populations of P. novaezelandiae exhibit such a pronounced pattern of homozygote excess and disturbance from genetic equilibrium in sympatry that it is unreasonable to consider them as a single panmictic population. It is concluded that significant biological discontinuities based on host origin exist within the currently recognised taxon. Such a conclusion is supported by data presented on qualitative differences in host recognition observed between different host-associated populations of P. novaezelandiae. Conservatively these discontinuities indicate host race development, although a viable alternate hypothesis would be the presence of cryptic, host-specific biological species within P. novaezelandiae. Hostrace development as found here is a well recognised phenomenon in insect-host and parasitoid-host relationships, although little studied in marine symbiotic relationships. Such a phenomenon has important implications for ecological, behavioural and physiological studies on marine symbionts in general.
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9

Ochieng'-Odero, James Patrick. "Aspects of the life cycle, biological performance and quality of the black lyre leafroller 'Cnephasia' jactatana (Walker)." Thesis, University of Auckland, 1988. http://hdl.handle.net/2292/2480.

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The thesis answers the general question of whether the quality of artificially reared insect species should be based on performance tests for intended use or whether quality should be based on a more holistic biological approach. The empirical research is carried out using the lepidopteran leafroller 'Cnephasia' jactatana (Walker). The thesis defines biological performance and quality in terms of the success of an insect population in survival and reproduction and regards the laboratory environment as an artificial habitat that insects must colonise in order to survive and reproduce. Changes in biological performance that occurred during 12 successive generations of laboratory rearing were due to selection, acclimatisation and domestication and not adaptation. Artificial colonisation is theoretically successful within a limited range of environmental factors. As the inherent genetic variability of the founder population determines the resilience of the population to changes in performance, the ranges of environmental factors during colonisation should be wide to 'capture' much of the variability. Using body size (weight) as an aspect of overall quality, the thesis presents evidence that the final instar larva of C. jactatana has a threshold mechanism (larval critical weight, LCW) that determines pupal and adult size. There is a proportionate decrease in weight from the maximum weight that a larva attains in the final instar (LMW) to pupa ( described as constant DP ) and to adult (DA). There is a direct relation between the latent feeding period (period between attaining an LCW and LMW), LMW, pupal and adult size, and the reproductive performance (fecundity ). Within the experimental conditions diet quality, temperature, photoperiod and artificial selection had no effect on the larval critical weight, DP or DA, the larval threshold mechanism in C. jactatana is probably a mechanical trigger that initiates pupation. Diet quality, temperature and thermophotoperiods affected pupal size, adult size and reproductive performance. Photoperiod had no significant effects on size and reproductive performance. Positive assortative selections for slow development and low pupal weight significantly decreased pupal and adult size, and reproductive performance. Selection for fast development and heavy pupal weight for three generations had no significant effect on size or reproductive performance. Larval critical weight is demonstrated as useful to define quality indices and predict the performance of laboratory reared insects. The general conclusion of the thesis is that insect quality should be defined more in terms of the success in survival and colonising ability rather than solely on the success for 'intended role' or 'fitness for use'.
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10

Bojarski, Christina. "Seasonal changes in pituitary and plasma prolactin concentrations, and the role of Prolactin in the control of delayed implantation in female Miniopterus schreibersii." Thesis, Rhodes University, 1993. http://hdl.handle.net/10962/d1005452.

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Mammotropes were successfully identified in the anterior pituitary gland of Miniopterus schreibersii using immunocytochemical (ICC) staining at the light and electron microscopy level. Mammotropes were distributed throughout the gland, were polygonal in shape and during secretory activity contained numerous large secretory granules (350 - 800nm). Using double ICC labelling, prolactin and growth hormone were never co-localiszed and found in individual cells only. Plasma prolactin levels were successfully measured on a monthly basis using radioimmunoassay and monthly pituitary prolactin levels were quantified using morphometric analysis of immunogold ICC staining and densitometry with polyacrylamide gels. Seasonal changes in the ultrastructure of mammotropes, and pituitary and plasma prolactin concentrations in female Miniopterus schreibersii indicated that there was an increase in prolactin secretion during the second half of the period of delayed implantation and that prolactin secretion remained elevated during normal embryonic development and lactation. This suggests that prolactin may be part of the luteotropic and lactogenic complex, and that the hormone might be responsible for terminating the period of delayed implantation. The latter is supported by experiments, where exogenous prolactin initiated precocious implantation during early delayed implantation, and treatment with bromocryptine (which inhibits prolactin synthesis) retarded implantation. Activation of mammotropes to synthesise prolactin and an increase of plasma prolactin levels occurred shortly after the winter solstice (21 June), suggesting that increasing daylength may be the environmental cue, which terminates the period of delayed implantation in Miniopterus schreibersii.
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11

Geerts, Sjirk. "Assembly and disassembly of bird pollination communities at the Cape of Africa." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/6904.

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Thesis (PhD (Botany and Zoology))--Stellenbosch University, 2011.
ENGLISH ABSTRACT: With the current global decline in pollinators, and the concurrent decline in plant species, pollination research is becoming increasingly important. However, studies outside Europe and North-America and on groups other than insects are needed to make generalisations possible. In this thesis I study how pollination structures plant and bird communities in a biodiversity hotspot, the Cape Floristic Region of South Africa. I show that bird-plant pollination mutualisms are an important ecological factor structuring ornithophilous Proteaceae and nectar-feeding bird communities. This close association between plant and bird communities suggests an important role for community wide pollination mutualisms. How these mutualisms disassemble in reaction to a range of anthropogenic impacts is determined. Firstly, I use experimental manipulation of honeybee density to test whether honeybee farming affects nectar-feeding birds. Hive addition increased honeybee abundance far above natural levels but nectar-feeding bird pollinators were not consistently affected. Secondly, I document the impact of a two lane tar road on the bird pollination community. The two-fold decline found in pollination along roadsides, should have important implications for the way we view and manage road verges for ecological processes. Thirdly, I investigated how fragmentation affects bird-pollination communities by assessing an endangered, bird-pollinated plant, Brunsvigia litoralis. The only flower visitor at the urban sites, the shorter billed Greater Double-collared Sunbird is unable to access the nectar due to a long perianth tube. The longer billed Malachite Sunbird was the sole pollinator of B. litoralis at the rural site, significantly increased seed set. The lack of ecological analogs in these urban fragments might place pollinator specialist plants, such as B. litoralis, at risk. Fourthly, fire is a frequent disturbance in communities of bird-pollinated plants. In a before/after fire observation study and a burnt/unburnt transplant study, birds visited flowers in the “before fire” and “unburnt” areas only. The results are surprising given the large number of bird-pollinated plants flowering in the early post-fire vegetation. Lastly, I find that alien invasive plant species are incorporated into the native pollination community in a spectacular way; sunbirds adapt to a hummingbird-like, hovering lifestyle to obtain nectar. Alien invasive plants greatly increase nectar-feeding bird abundance; in turn, birds enhance seed set in these alien plants. I conclude by asking whether the disassembling of bird pollination communities really matters. To answer this question I report on a decade of demographic data on the geophytic bird-pollinated Brunsvigia orientalis. In the demographic analysis, the elasticity component for reproduction was more important than expected for a long lived plant. Reduced population growth in the shade and a large investment in a winged inflorescence, suggest B. orientalis is a light demanding, well dispersed, gap colonising species. The link between pollination and seed has been made before, but I take this one step further and show that pollination intensity predicts population growth rate. By linking plant demography and pollination, I was able to predict the future of plant populations under variable pollination conditions. The disassembly of bird pollination communities only becomes important for population persistence once the mutualism has almost entirely broken down.
AFRIKAANSE OPSOMMING: Met die huidige globale afname in bestuiwers en die gelyktydige afname in plant spesies, word bestuiwing navorsing toenemend belangrik. Studies buite Europa en Noord-Amerika en op groepe anders dan insekte is nodig on veralgemenings moontlik te maak. In hierdie tesis bestudeer ek hoe bestuiwing struktuur gee and plant en voël gemeenskappe in 'n biodiversiteit hotspot, die Kaapse Floristiese Ryk van Suid-Afrika. Ek wys dat voël-plant bestuiwings mutualismes 'n belangrike ekologiese faktor is in die strukturering van voël bestuifde Proteaceae gemeenskappe en nektar-etende voël gemeenskappe. Hierdie noue assosiasie tussen plant en voël gemeenskappe impliseer 'n belangrike rol vir gemeenskapwye bestuiwings meganismes. Ek bepaal hoe hierdie mutualismes aftakel in reaksie op 'n verskeidenheid van antropogeniese impakte. Eerstens gebruik ek 'n eksperimentele manipulasie van heuningby getalle om te toets of bye boerdery nektar-etende voëls affekteer. Byekorf toevoeging het heuningby getalle laat toeneem tot ver bo natuurlike vlakke maar nektar-etende voël bestuiwers is nie konsekwent beïnvloed nie. Tweedens dokumenteer ek die impakte van 'n twee baan teerpad op die voël bestuiwings gemeenskap. Die twee-malige afname in bestuiwing langs paaie sal belangrike implikasies hê vir die manier hoe ons pad reserwes sien en bestuur met betrekking tot ekologiese prosesse. Derdens bestudeer ek hoe fragmentasie die voël-plant gemeenskappe affekteer deur die bedreigde voël-bestuifde Brunsvigia litoralis te assesseer. Die enigste besoeker in die meer stedelike area, die Groot-rooibandsuikerbekkie, wat 'n korter snawel het, is nie in staat om die nektar te bereik nie, weens 'n te lang blombuis. Die Jangroentjie suikerbekkie met sy langer snawel is die enigste bestuiwer van B. litoralis in die meer landelike area, met 'n betekenisvolle vermeerdering in saad vorming. Die gebrek aan ekologies analogiese spesies in die stedelike fragmente kan 'n risiko inhou vir bestuiwer gespesialiseerde plante soos B. litoralis. Vierdens, vuur is 'n gereelde versteuring van voël-plant gemeenskappe. In 'n voor/na vuur observasie studie en 'n brand/nie-brand verplasing studie, het voëls blomme net in die “voor brand” en “nie-brand” areas besoek. Hierdie resultate is verrassend siende die groot hoeveelheid voël-bestuifde plante wat blom direk na brande. Laastens het ek gevind dat uitheemse indringer plante geïnkorporeer word in die inheemse bestuiwers gemeenskappe op 'n skouspelagtige manier; suikerbekkies pas aan tot 'n kolibri-tipe, fladderende lewenswyse om nektar te bekom. Uitheemse indringer plante het nektar-etende voël hoeveelhede laat toeneem; in reaksie het voëls saad opbrengs vermeerder. In konklusie vra ek of hierdie aftakeling van die voël bestuiwers gemeenskap belangrik is. Om hierdie vraag te antwoord assesseer ek 'n dekade van demografiese data van die geofietiese, voël-bestuifde plant, Brunsvigia orientalis. In die demografiese analises was die elastisiteit komponent van reproduksie belangriker as verwag vir 'n langlewende plant. Verminderde populasie groei in die skaduwee en 'n hoë investering in 'n gevlerkte bloeiwyse suggereer dat B. orientalis 'n lig afhanklike, goed verspreide, gaping koloniserende spesie is. Die skakel tussen bestuiwing en saadvorming is voorheen gemaak, maar ek neem dit een stap verder en wys dat bestuiwings intensiteit populasie groeikoers voorspel. Deur plant demografie en bestuiwing te koppel was ek in staat om die toekoms van populasies onder variërende bestuiwings kondisies te voorspel. Die aftakeling van voël bestuiwings gemeenskappe word slegs belangrik vir populasies se voortbestaan wanneer die mutualisme amper heeltemal verdwyn het.
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12

Waghorn, Tania Susanne. "Molecular and Ecological Aspects of Heliothis Armigera." Thesis, University of Auckland, 1999. http://hdl.handle.net/2292/522.

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The species status and host range of Heliothis armigera was investigated. DNA profiling, mitochondrial DNA sequencing, RAPD's, along with traditional morphological and crossing methods were used to investigate micro, macro and mega-population structuring. Thirty-six new host records were added, of which a number are important common weeds and crops. Mortality due to parasitoids and fungal infections were quantified on many host species. Genetic analysis of the COII and the AT-rich regions of the mitochondrial DNA showed very high levels of variation, as did the DNA profiling using the probes (CA)n and 33.15. The morphological analyses also showed variation, but to a lesser degree and without statistical significance. The variation found at all levels and in all aspects is discussed with respect to caterpillar host-plants and geographical location. All host-plant populations of caterpillars showed very high levels of genetic variability. However, the population of caterpillars found on Sulla (Hedysarium coronarium) was significantly more variable than those found on Lotus and Lucerne when compared using DNA profiling. The sequences obtained from the two mtDNA regions also showed considerable variation, a great percentage of which was uninformative. This variation did not allude to any structuring of caterpillar populations with respect to host-plant or geographical location. H. armigera is genetically a very variable species which does not equate with any population structuring present in the host-plant or geographical populations investigated here. This study has greatly increased the general understanding of this insect, and has elucidated a portion of the genetic makeup, but not helped in the development any new control methods.
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13

Haw, James. "Effects of Argentine Ant (Linepithema Humile) on Arthropod Fauna in New Zealand Native Forest." Thesis, University of Auckland, 2006. http://hdl.handle.net/2292/625.

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Although Argentine ant(Linepithema humile), a highly invasive ant species, has been in New Zealand for at least l4 years, little is known about their ecology and potential for invasion. Increasing spread and establishment of populations throughout New Zealand is disturbing because of the devastating impacts documented on native invertebrate biodiversity overseas. The primary aim of this study was to determine the impacts of Argentine ants on arthropods in native forest habitats in west Auckland. Pitfall traps at invaded and uninvaded sites were used to quantify ant and non-ant arthropod faunas. Argentine ants did not adversely affect native host ant communities. Moreover, two ant species appeared to be resistant to invasion. Argentine ant invasion reduced the abundance of a few orders of invertebrates while several taxa were more abundant in the presence of Argentine ants. Distribution and foraging activity of Argentine ant populations were monitored in this study from 2000-2003. Also, rate of spread was investigated to evaluate whether native forest habitats would be at risk from invasion. Measurements of foraging ant trails on monitored tree trunks revealed seasonal distribution patterns involving high activity in summer/autumn and low activity in winter/early spring. Argentine ants were found to be established primarily along the edge of the forest and did not invade into the interior of the forest during the study period. An Argentine ant poisoning operation on Tiritiri Matangi Island in January 2001 provided the opportunity to document the results of the eradication trial. In addition, pitfall traps placed at two treated sites and one untreated site were used to compare pre-poison and post-poison effects on ant and non-ant invertebrate communities. Fipronil baiting at 0.01% effectively reduced Argentine ants at the study sites and very few ants were observed in both tree count and pitfall trap recordings two months after poisoning. The invasion of Argentine ants on Tiritiri Matangi Island decimated native host ants and no recovery was detected throughout the study. Several groups of invertebrates appeared to benefit from the removal of Argentine ants while a few showed no detectable changes. Conservation implications resulting from the findings of this study are discussed Also, potential future research involving Argentine ants are outlined.
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14

Beck, Nancy Gunther. "Lepidopterous pests on vegetable brassicas in Pukekohe, New Zealand: their seasonality, parasitism, and management." Thesis, University of Auckland, 1991. http://hdl.handle.net/2292/1982.

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The vegetable brassicas of cabbage, broccoli, and cauliflower are grown in Pukekohe for the Auckland fresh-produce markets. These brassicas are attacked by three major lepidopterous pests: diamondback moth (DBM) (Plutella xylostella (L)) (Yponomeutidae), white butterfly (WB) (Pieris rapae (L.)) (Pieridae), and soybean looper (SBL) (Thysanoplusia orichalcea (F.)) (Noctuidae). Current grower strategy to combat these pests is calendar-scheduled insecticide applications. The goal of this thesis is to develop pest management alternatives. The seasonality of these three pests is discussed. DBM and WB are each under biological control by a larval and a pupal parasitoid, but this natural control is not sufficient to allow economic harvests in cabbage and was not synchronized. No parasitoids of SBL were found. The importation of additional natural enemies is discussed. A scouting system of the percent of cabbage plants infested coupled with an action threshold of. 15%-20% infested plants, resulted in good yields in field trials and allowed up to a 50% reduction in insecticide applications over the growth period when compared to a 14-day calendar schedule. Implementation of the 15% infested threshold in commercial cabbage fields resulted in up to an 83% reduction in insecticide applications with no yield decrease in quality or quantity. Application of this 15% infested plant threshold to broccoli and cauliflower decreased insecticide applications by 40% and 17%, respectively. Study of larval biology indicated that all of the lepidopterans preferentially fed on leaves; timing of the first insecticide application in broccoli and cauliflower to coincide with floret initiation decreased insecticide applications by 80% and 67%, respectively. Laboratory and field trials comparing DBM oviposition preference, larval survivability, and parasitism rates between cabbage, broccoli, and cauliflower are discussed. Knowledge of lepidopterous pest seasonality and biology, linked to careful timing of insecticide applications to coincide with threshold levels of pests, can take full advantage of natural enemies and reduce insecticide input in the vegetable brassicas of cabbage, broccoli, and cauliflower with no decrease in crop quality.
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15

Hines, Dustin J., and University of Lethbridge Faculty of Arts and Science. "The role of cues and the hippocampus in home base behaviour." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2004, 2004. http://hdl.handle.net/10133/646.

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The thesis examines the ability of animals to construct a home base. The home base is a point in space where animals rear, groom, and circle and is a primary element in organized spatial behaviour (Eilam and Golani 1989). Once animals establish a home base, they make outward trips and stops, and after a series of trips and stops they return again to the home base. The home base behaviour of animals acts as a platform for asking questions about the cognitive organization of an environment. The thesis describes five main findings. Control and hippocampectomized animals use (1) proximal and (2) distal cues to form a home base and organize their behaviour. (3) Control and olfactory bulbectomized animals form home bases in the dark where as hippocampectomized animals are impaired suggesting self-movement but not olfactory cues play a role in home base behaviour. A final set of experiments demonstrated that control and hippocampectomized animals learn the position of (4) proximal and (5) distal cues so that in the cue's absence, animals still form a home base at that position. The demonstration that a central feature of exploratory behaviour, establishing a home base, is preserved in hippocampectomized rats in relation to proximal, distal, and conditioned visual cues - reveals that exploratory behaviour remains organized after hippocampal lesions. The inability of hippocampectomized rats to form a virtual home base in the absence of visual cues is discussed in relation to the idea that the hippocampus contributes to inertial behaviour that may be dependent upon self-movement cues.
xv, 232 leaves : ill. ; 29 cm.
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Gutzwiller, Sarah C. "POSTCRANIAL SKELETAL PNEUMATICITY, BONE STUCTURE, AND FORAGING STYLE IN TWO CLADES OF NEOGNATH BIRDS." Ohio University Honors Tutorial College / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors1275601248.

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17

Calderone, Carli E. "Stem Cell Research: Science Education and Outreach." Miami University Honors Theses / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=muhonors1268751337.

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18

Burger, Lena F. "Characterisation of a novel tick-derived dendritic cell modulator, Japanin." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:cbe8d327-8907-40ab-b410-36c21011f4db.

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Dendritic cells (DC) play a key role in immunity and represent a great target for modulation, because of their ability to prime T cells and direct their polarisation into effector subsets. Ticks release immunomodulatory compounds in their saliva, possibly in order to evade host immune responses during feeding. We have recently reported that Rhipicephalus appendiculatus ticks produce ‘Japanin’, a secretory lipocalin that arrests differentiation of monocytes into DC and reprogrammes maturation of DC in response to various stimuli towards a tolerogenic phenotype . Japanin was cloned and recombinantly expressed in a baculovirus system for subsequent immunological and biochemical analysis. This study was set out to further investigate the immunomodulatory activity of Japanin as well as the underlying mechanism of action. We have discovered that Japanin prevents DC-mediated proliferation and polarisation of allogeneic T cells. Experiments with labelled Japanin have demonstrated that it binds predominantly to ex vivo generated human monocyte-derived DC (moDC) and to a reduced degree to monocyte and DC populations in peripheral blood, yet to no other blood leucocytes. We have identified CD206, also known as the mannose receptor, as a Japanin-binding receptor on moDC. This identification has been achieved by crosslinking and subsequent pull-down of Japanin-receptor complexes from moDC. Affinity studies with recombinant CD206 constructs have confirmed the binding to Japanin. Moreover, the binding has been verified by specific siRNA knock-down of CD206 in moDC, which resulted in significantly decreased binding of Japanin. Unexpectedly, CD206 has appeared to be dispensable for at least most of the DC-modulatory activity of Japanin. Therefore, attempts were made to determine other factors in the mode of action of Japanin, through which we have found that IL-10 is not essentially involved. Further results have suggested that the activity of Japanin demands cell contact. Collectively, we have come to the conclusion that the mechanism of action of Japanin might require internalisation by DC, potentially enabling modulation of intracellular pathways involved in the regulation of DC maturation.
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Kumar, Mohit. "Image Performance Characteristics of Bio-Inspired Image Sensor." University of Akron / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=akron1386765298.

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20

Vice, President Research Office of the. "Species Showdown." Office of the Vice President Research, The University of British Columbia, 2006. http://hdl.handle.net/2429/2700.

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21

Middleton, Danielle Mary Rose Lea. "The prevalence of Salmonella and the spatial distribution of its serovars amongst New Zealand's native lizards : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Zoology at Massey University, Palmerston North, New Zealand." Massey University, 2008. http://hdl.handle.net/10179/906.

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This thesis considers the prevalence and spatial distribution of Salmonella serovars amongst wild endemic lizards on offshore islands around the coast of New Zealand. The mean test prevalence of faecal excretion of Salmonella was 4.7%. Skinks (Scincidae) were more likely (8.5%) to be carriers of Salmonella than geckos (1.6%). Each island was host to between one and three Salmonella serovars that were not found on any other islands in this study. Two exceptions were Salmonella Bousso and Salmonella Mana which were found on two islands within the same geographical area. Based on the findings of this study, different islands are likely to be hosts to different Salmonella serovars which could have implications for future translocations of native lizards. I also assessed the prevalence and spatial distribution of faecal excretion of Salmonella, Aeromonas and Hafnia alvei within Mana Island. The prevalence of Salmonella on Mana Island was estimated at 5.8%. Salmonella was found predominantly in skinks (10.0%) and less often in geckos (4.1%). H. alvei was found at a prevalence of 1.9%. No Aeromonas species were cultured from any of the cloacal swabs, suggesting that the 95% confidence interval for the true prevalence is 0-3%. Each site sampled in this study was host to one or more unique serovar of Salmonella not found at any of the other sites. The results of this study indicate that Salmonella serovars may become established within populations of lizards and is not spread between them. This may be due to a lack of dispersal of lizards between sites, raising important considerations for the translocation of native lizards. I investigated the prevalence of faecal excretion of Salmonella, H. alvei and Aeromonas by New Zealand native lizards from two captive populations. The mean prevalence of faecal excretion of Salmonella in the captive lizards sampled was 11.5%. There was a higher prevalence of Salmonella within captive population A (22.0%) than in population B (3.6%). No Aeromonas was cultured from any of the lizards. H. alvei was found at a prevalence of 5.2%. The prevalence of Salmonella and H. alvei was significantly higher in captive lizards than in wild populations. Captive lizards may, therefore, not be appropriate founders for new populations of wild lizards. Finally I assessed the different efficiencies of two media and two temperatures in isolating six Salmonella serovars from a reptilian source. All serovars grew equally well at 37°C and 27°C. For most serovars XLD agar was the more successful media than MacConkey agar but the success of different culture media depended on the serovar being cultured. Because lizards are frequently host to a wide range of Salmonella serovars, screening samples using multiple microbiological methods is likely to give the best chance of isolating all Salmonella serovars present.
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22

Meynier, Laureline. "Feeding ecology of the New Zealand sea lion (Phocarctos hookeri) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor Philosophy in Zoology at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/901.

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The New Zealand (NZ) sea lion Phocarctos hookeri is the only pinniped endemic to NZ with a population of approximately 12,000 individuals. Its breeding range is currently restricted to NZ sub-Antarctic islands, and it has failed to recolonise its pristine distribution around the NZ main islands despite its protection since 1881. The current hypothesis is that the population growth of this pinniped is limited by the distribution of suitable prey on the Auckland Islands (50°30'S, 166°E) shelf, and by the direct and indirect pressure exerted by the arrow squid Nototodarus sloani fishery. However, this hypothesis has not been fully tested to date as there has been limited information on the diet of the NZ sea lion and their potential prey. The objective of this thesis is to analyse the diet of NZ sea lions over several years with particular emphasis on the most reproductively important segment of the population: lactating females. This thesis provides the first quantification by percentage mass of the diet of NZ sea lion using a combination of stomach content analysis, qualitative fatty acid (FA) analysis, and quantitative FA signature analysis (QFASA). Stomach contents and blubber FAs were analysed from 121 individuals incidentally caught (by-caught) in the southern arrow squid fishery from the years 1997 to 2006. The blubber FAs of 78 freeranging lactating females captured at Enderby Island, Auckland Islands, were also examined during January and February of 2000 to 2005. Data obtained from both stomach analysis and QFASA indicate that arrow squid, rattails Macrouridae, hoki Macruronus novaezelandiae and red cod Pseudophycis bachus are key prey species for NZ sea lions in the Auckland Islands region. Because these prey species live mostly at depths greater than 200 m, lactating females must undertake long foraging trips and dive regularly to greater depths than other sea lion species. Data from QFASA indicates that this foraging pattern is conducted over an extended period through the summer and autumn. The daily food requirement of a lactating female was estimated by a simple energetic model to be greater than 20% of its body mass. During years of low arrow squid recruitment such as 1999 and 2001, the amounts of squid required by the NZ sea lion population may have been similar to the amount harvested by the fishery, suggesting that resource competition is likely to occur between the arrow squid fishery and NZ sea lions in years of low squid abundance. Half of the fishing activity of the southern squid fishery occurs in the north of the Auckland Islands shelf where NZ sea lions forage, leading to incidental captures every year. This research emphasises that management of the NZ sea lion must not only consider the direct interactions with the arrow squid fishery, but also the likelihood of food resource competition between the fishery and NZ sea lions.
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23

Tingey, Leigha. "Post-occupancy Evaluation at the Zoo: Behavioral and Hormonal Indicators of Welfare in Orangutans (Pongo pygmaeus abelii)." PDXScholar, 2012. https://pdxscholar.library.pdx.edu/open_access_etds/901.

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An increased understanding of species-specific behavioral needs has lead zoos to focus on providing more naturalistic and stimulating environments. Scientific assessments of how changes in habitat affect animal behavior are necessary in improving overall animal welfare. This study examined the move of three orangutans housed at the Oregon Zoo into a new and innovative exhibit. Post-occupancy evaluation (POE), which offers systematic information regarding the success or failure of the built environment (Maple & Finlay, 1987), was utilized to effectively evaluate the results of the move. The collection of behavioral data and adrenal activity monitoring through collection of non-invasive saliva, urine and hair provided a comprehensive methodology for comparing changes in behavior and physiological functioning. Behavioral results showed that following the move to the new enclosure animals spent less time inactive, more time at higher elevations and utilized exhibit structures at a greater frequency. Hormonal results suggest that detection of cortisol in orangutan hair could be a useful tool for monitoring chronic stress.
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24

Francis, Malcolm 1954. "Population dynamics of juvenile snapper (Pagrus auratus) in the Hauraki Gulf." Thesis, University of Auckland, 1992. http://hdl.handle.net/2292/1976.

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The population dynamics of juvenile snapper, Pagrus auratus, were investigated in the Hauraki Gulf, north-eastern New Zealand, between 1982 and 1990. Attention focused on age and growth, temporal and spatial variation in abundance, and recruitment. Daily increment formation was validated in the sagittae of snapper up to about 160 days old. Increment width varied with time of year, and snapper age, and increments were not resolvable with a light microscope during winter. Increment counts inside a prominent metamorphic mark showed that larval duration was 18-32 days, and was inversely related to water temperature. Spawning dates were back-calculated from increment counts in settled juveniles, and ranged from September to March with a peak in November-January. The onset of spawning was temperature dependent. Fast-growing snapper had smaller sagittae than slow-growing snapper, indicating an uncoupling of otolith and somatic growth. Snapper gonads differentiated first as ovaries during the second year of life, and then some juveniles changed sex to become males during their third year. Sex change occurred before maturity, so snapper are functionally gonochoristic. Growth was slow during the larval phase, but increased rapidly after metamorphosis to about 0.6-0.9 mm.day-1. From the first winter, growth followed a well-defined annual cycle, with little or no growth during winter, and linear growth of 0.16-0.43 mm.day-1 during spring-autumn for 0+/1+ and 1+/2+ snapper. Snapper grew faster at higher temperatures. Trawl catch rates were affected by numerous gear and environmental factors, but probably provided reasonable estimates of snapper relative abundance. Recommendations are made for improving snapper trawl survey procedures. There was a strong annual abundance cycle in the Kawau region, peaking in spring, and declining to a minimum in winter. Snapper were patchily distributed at a spatial scale of 1-2 km, probably because of preference for specific micro-habitats. Year class strength of 1+ snapper varied 17-fold over seven years, and was strongly positively correlated with autumn sea surface temperature during the 0+ year. The strengths of the 1991 and 1992 year classes are predicted to be below average, and extremely weak, respectively.
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25

Page, Roderic D. M. (Roderic Dugald Morton). "Panbiogeography: a cladistic approach." Thesis, University of Auckland, 1990. http://hdl.handle.net/2292/1999.

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This thesis develops a quantitative cladistic approach to panbiogeography. Algorithms for constructing and comparing area cladograms are developed and implemented in a computer program. Examples of the use of this software are described. The principle results of this thesis are: (1) The description of algorithms for implementing Nelson and Platnick's (1981) methods for constructing area cladograms. These algorithms have been incorporated into a computer program. (2) Zandee and Roos' (1987) methods based on "component-compatibility" are shown to be flawed. (3) Recent criticisms of Nelson and Platnick's methods by E. O. Wiley are rebutted. (4) A quantitative reanalysis of Hafner and Nadler's (1988) allozyme data for gophers and their parasitic lice illustrates the utility of information on timing of speciation events in interpreting apparent incongruence between host and parasite cladograms. In addition the thesis contains a survey of some current themes in biogeography, a reply to criticisms of my earlier work on track analysis, and an application of bootstrap and consensus methods to place confidence limits on estimates of cladograms.
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26

Pankhurst, Patricia Melva. "Growth, development and visual ontogeny of two temperate reef teleosts Pagrus auratus, (Sparidae) and Forsterygion varium, (Tripterygiidae)." Thesis, University of Auckland, 1991. http://hdl.handle.net/2292/2000.

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Growth, development and behaviour were examined in artificially reared larval Pagrus auratus and Forsterygion varium, from the time of hatching. Yolk-sac larval P.auratus hatched at a small size (2.00mm SL), without functional eyes, mouth or digestive tract, and for three days spent long periods at rest. Growth was initially rapid but slowed by 3 days as yolk reserves neared depletion. By days 4-5, the mouth had opened, eyes were functional, yolk was depleted, and a rudimentary gut had formed. Larvae were now able to maintain a horizontal swimming mode and were actively searching for and attacking prey. First feeding was observed in some larvae. Growth was retarded during the transition from endogenous to exogenous nutrition and then increased as feeding proficiency improved. Yolk-sac F.varium hatched at a larger size (4.78mm SL), with functional eyes and jaws. Larvae were able to maintain a horizontal swimming mode from hatching. First feeding was observed from the first day after hatching. F.varium larvae grew steadily from the time of hatching. Ocular morphology was examined in larval, juvenile and adult P.auratus and F.varium. There was a 96 fold increase in eye size, from 0.23mm diameter in a 4 day old larval P.auratus (3.4mm SL) to a maximum diameter of 22mm in an adult of 333mm body length. F.varium displayed a 26 fold increase in eye size, from 0.28mm diameter in the smallest larva (5.00mm SL) to a maximum eye diameter of 7.2mm in a 11gmm long adult. Larval fish had pure cone retinae, however putative rod precursor cells were present from hatching in F.varium and from 18 days in P.auratus. Juvenile and adult fish had duplex retinae with cones arranged in a square mosaic in which 4 twin cones surround a central single cone. Hypertrophy of cone ellipsoids with increasing eye size, resulted in maintenance of a closely packed array in fishes of all sizes. The appearance of retinomotor movements was coincident with the development of a duplex retina in both species. Theoretical spatial acuity (calculated as a function of cone spacing and focal length of the lens) was poor in the smallest larval fish (2° 1' and 1° 8' minimum separable angle in 4 and 1 day old P.auratus and F.varium respectively) but improved to asymptotic values in adults (3'- 4', and 9' in P.auratus and F.varium respectively). Behavioural acuity (determined using the optokinetic response) of 4 day old larval P.auratus (37° 30') and 1 day old F.varium (29°) was very much lower than histological estimates. Behavioural acuity improved to 8° 8' in 16 day old P.auratus and 4° 18' in 14 day old F.varium, but did not attain theoretical estimates for fish of that size (55' and 54'). A rudimentary retractor lentis muscle was first apparent in larval fish 1 week after hatching, and was coincident with the formation of a posterior lental space. Presumably larval fish eyes were incapable of accomodative lens movements until this time. A relative measure of Matthiessen's ratio (distance from lens centre to boundary of the pigmented retinal epithelium/lens radius) measured histologically, decreased from 4.2 and 2.7 in 3 day old P.auratus and newly hatched F.varium, to 2.2 and 2.3 in larvae 22 and 16 days of age respectively. This suggests that growth of the retina and lens were not symmetrical in the eyes of very small larval fish. If Matthiessen's ratio holds for little eyes, then they will initially be strongly myopic. This may account in part for the mismatch between behavioural and theoretical acuity. Perceptive distances of first feeding larval P.auratus and F.varium, estimated for prey items equal in dimensions to maximum jaw widths, were very small (0.2mm and 0.4mm for prey 0.15mm and 0.2mm in size respectively), but increased with increasing body size to 2.1mm and 4.0mm for prey 0.3mm in size, at 16 and 14 days of age respectively. These data have implications for larval feeding in the wild.
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27

Laslie, Kathryn C. "Investigations of Biotremors in the Veiled Chameleon (Chamaeleo calyptratus)." TopSCHOLAR®, 2018. https://digitalcommons.wku.edu/theses/3067.

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While substrate-borne vibrations are utilized by different reptile species, true conspecific communication via biotremors has not yet been demonstrated in reptiles. This study follows a preliminary report that the veiled chameleon (Chamaeleo calyptratus) could produce biotremors in communicative contexts. I tested chameleon behavioral sensitivity to vibrations by placing them on a dowel attached to a shaker emitting vibrations of 25, 50, 150, 300, and 600 Hz and then measured their changes in velocity before and after the stimulus. I then paired chameleons in various social contexts [anthropogenic disturbance (human disruption of animal); dominance (malemale; female-female C. calyptratus); courtship (male-female C. calyptratus); heterospecific (C. calyptratus + C. gracilis); and predator-prey (adult + juvenile C. calyptratus)] and used a video camera and accelerometers to record their behavior. This study demonstrates that chameleons produce biotremors and that receivers exhibit a freeze response when exposed to a simulated biotremor stimulus. Furthermore, veiled chameleons produce biotremors in anthropogenic disturbance, conspecific dominance and courtship contexts, and these biotremors are elicited by visual contact with another adult conspecific and heterospecifics. Overall, two classes of biotremor were identified, "hoots” and “rumbles,” which differ significantly in dominant frequency and waveform. No correlation was identified between animal size and dominant frequency of the biotremors they produced as biotremors originate from rapid muscle contractions. Juvenile chameleons of two months of age are able to produce biotremors, suggesting this behavior may have multiple functions. Overall, the data suggest that the veiled chameleon has the potential to utilize substrate-borne vibrational communication during conspecific and possibly heterospecific interactions.
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28

Dalebout, Merel Louise. "Species identity, genetic diversity, and molecular systematic relationships among the Ziphiidae (beaked whales)." Thesis, University of Auckland, 2002. http://wwwlib.umi.com/dissertations/fullcit/3083930.

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Beaked whales (family Ziphiidae) are one of the least known of all mammalian groups. The majority of species have been described from only a handful of specimens. Found in deep ocean waters, these species are widespread and often sexually dimorphic. Little is known of intra-specific variation in morphology, and many species are very similar in external appearance. A reference database of mitochondrial DNA sequences was compiled for all 20 recognised ziphiid species to aid in species identification. All reference sequences were derived from validated specimens, which were often represented only by bone or teeth. DNA was obtained from this ‘historic’ material using ‘ancient’ DNA methods. For three species, holotypes were sampled. Phylogenetic analyses using this database led to the discovery of a new, previously unrecognised species of beaked whale (Mesoplodon perrini), new specimens of Longman's beaked whale (Indopacetus pacificus), a species known previously from only two partial skulls and the synonymy of a third (M. traversii = M. bahamondi). Phylogenetic reconstructions based on sequence data from three mitochondrial and two nuclear loci (total, 2815 bp) using neighbour joining, parsimony, and maximum likelihood methods, resolved many of the sister-species relationships in this group. Inferred relationships among Mesoplodon beaked whales indicated that cranial and tooth morphology may be far more variable between closely related species than previously assumed. No support was found for a linear-progression of tooth form as suggested by Moore (1968) in his phenetic evaluation of relationships among the Ziphiidae. The geographic distribution of Mesoplodon species with similar or divergent tooth morphology is likely due to a combination of sexual selection and selection for species recognition. Both hypotheses predict similar patterns, such as dissimilar tooth morphology among species with sympatric or parapatric distributions. However, only sexual selection appears to offer an explanation for why there are so many Mesoplodon beaked whales. Investigation of mtDNA diversity among a number of beaked whale species indicated that nucleotide diversity was generally lower in this group than in other wide-ranging oceanic cetaceans. The cause of this low diversity was not clear but may be indicative of overall low abundance. Particularly low levels of diversity were found in Baird's beaked whale Berardius bairdii , Arnoux's beaked whale B. arnuxii and the northern bottlenose whale Hyperoodon ampullatus. Strong geographic structure in haplotype frequencies was observed among a worldwide sample of Cuvier's beaked whales Ziphius cavirostris.
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29

Zhang, Yifei. "Fred Regulatory Network in Drosophila Neurogenesis." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1332015401.

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30

Campbell, Kirsten L. "A study of home ranges, movements, diet and habitat use of kereru (Hemiphaga novaeseelandiae) in the southeastern sector of Banks Peninsula, New Zealand." Master's thesis, Lincoln University. Bio-Protection and Ecology Division, 2006. http://theses.lincoln.ac.nz/public/adt-NZLIU20080317.131118/.

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The present study is part of the Kaupapa Kereru Programme. The main aim of the programme is to increase the numbers and range of kereru (Hemiphaga novaeseelandiae) on Banks Peninsula. Home ranges, movements, diet and habitat use of 15 kereru captured in Hinewai Reserve, Banks Peninsula, were investigated from February 2005 to February 2006. Hinewai Reserve is the largest tract of regenerating native forest in a highly modified urban-rural landscape. Phenology of 11 plant species predicted to be key kereru foods, was studied to determine the pattern of food availability in Hinewai Reserve. Twelve radio-tagged kereru resided in the Hinewai Reserve study site (Otanerito Valley and Sleepy Bay) and three resided in Akaroa. Ripe fruit was available from January to August; the height of the fruiting season was in autumn. The bulk of new leaf growth occurred in spring and early summer although new leaves were available on broom and tree lucerne year round. Peak flowering occurred in spring. Kereru in Akaroa ate a total of 21 plant species; six of these species were native and 15 introduced. Kereru in the Hinewai Reserve study site ate a total of 26 plant species; 20 of these species were native and six introduced. Fruit was preferred when readily available. Native fruit appeared to be preferred over fruit of introduced species in Akaroa, where both types were available. New foliage of introduced legumes and deciduous species appeared to be preferred over new foliage of native species at both sites during winter and spring. These species were important food sources prior to the breeding season and may be selected specifically for their nitrogen and protein content. Food is currently not a limiting factor for kereru survival or reproductive success. Considerable variation in the use and preference of vegetation types of individual kereru made it difficult to identify trends in habitat selection. Use and preference for many vegetation types was seasonal; this was certainly because of the availability of food species included in or close to these vegetation types. Overall, native vegetation communities were used more than communities dominated by introduced species and forest communities were used more than non-forest communities. Kanuka (Kunzea ericoides) was used most often for non-feeding activities and 67% of observed nests were built in kanuka. Annual home ranges and core areas in the Hinewai Reserve study site (mean of 15.9 and 2 ha respectively) were significantly larger than those found in Lyttelton Harbour, Banks Peninsula in previous research (mean of 8 and 0.08 ha respectively). Home ranges were larger when fruit was eaten, than when no fruit was eaten indicating that kereru are more sedentary when feeding on foliage. Kereru from the Hinewai Reserve study site made no excursions >5 km and no daily movements >2 km. Kereru from Akaroa and Sleepy Bay travelled into Otanerito Valley to feed on horopito in autumn, indicating that there may have been a lack of fruit in their local areas during autumn. No kereru in Otanerito Valley travelled outside of the valley. The distribution of high quality food sources is likely to have caused the observed differences in home range and core area size between localities. Kereru in Lyttelton Harbour may have been restricted to small patches of high quality resources in a study area consisting largely of unsuitable habitat. In Hinewai Reserve, high quality resources were spread over larger areas and were more uniformly distributed. The density of kereru was unknown at both study sites, and this confounded assessment of habitat quality. However, it is likely that the Hinewai Reserve study site would support a higher number of kereru. The main factor limiting population growth in the present study was failure of nests at the egg and chick stage. The fledge rate was 17%. Two of fifteen adult kereru died. Control of predators should be the first aspect of management that is focused on, and will almost certainly increase reproductive success of kereru and loss of breeding adults. As the population of kereru on Banks Peninsula increases due to predator control in existing kereru habitat, food may become a limiting factor. Habitat can be improved for kereru by planting a diverse range of plant species that provide food year-round. Native fruiting species are greatly recommended for habitat enhancement and should be selected so that fruit is available for as much of the year as possible. Native and introduced legumes should also be made available as foods for winter and spring. As most land on Banks Peninsula is privately owned, co-operation and enthusiasm of the community is critical for successful management. Information and support needs to be given to landowners wishing to enhance their properties for kereru.
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31

Brown, Samuel David James. "Molecular systematics and colour variation of Carpophilus species (Coleoptera: Nitidulidae) of the South Pacific." Diss., Lincoln University, 2009. http://hdl.handle.net/10182/1430.

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The sap beetle genus Carpophilus Stephens (Coleoptera: Nitidulidae) is a large genus consisting of over 200 species and are found worldwide. Several species are important pests of crops and stored products, and are frequently intercepted as part of biosecurity operations. The genus is poorly known taxonomically, and there are several species groups that are challenging to identify by morphological methods. In particular, two species found across the Pacific, C. maculatus Murray and C. oculatus Murray are frequently confused with each other. These two species are similar in size and colour, but differ primarily by the shape of the colour pattern on their elytra. However, this colour pattern is highly variable within both species, leading to ambiguity in the indentification of these species. Within C. oculatus, three subspecies have been described based on differences in the male genitalia and pronotal punctation: C. o. oculatus and C. o. gilloglyi Dobson are distributed widely across the Pacific, while C. o. cheesmani Dobson is known only from Vanuatu. A search of literature records and specimen collections revealed 32 species of Carpophilus recorded from the Pacific region. In addition there remain several unidentified specimens representing at least four species, two of which will be described subsequent to this research. A number of species recorded in the literature may have been misidentified, and these require further field collections and inspection of museum specimens to confirm their presence in the Pacific. To test the validity of the subspecies of C. oculatus, and its distinctiveness from C. maculatus, a phylogeny of available specimens of Carpophilus was inferred from one mitochondrial gene (cytochrome c oxidase subunit I (COI)), and two nuclear genes (28S ribsomal RNA (28S) and the internal transcribed spacer 2 (ITS2)). These data show large genetic distances between the three subspecies of C. oculatus of 7-12%. Given these distances are similar to those between other species in the genus, this indicates these subspecies may be elevated to full species. The data also consistently support a monophyletic relationship between C. o. oculatus and C. o. gilloglyi. Nuclear genes also support C. o. cheesmani as part of a clade with the other subspecies, but these relationships are unresolved in COI. Carpophilus maculatus was not supported as being the sister taxon of the C. o. oculatus and C. o. gilloglyi clade. Other relationships within Carpophilus were unresolved, possibly due to a combination of incomplete taxon sampling, and saturation of substitutions within the COI gene. Phylogeographic analysis of specimens collected from several localities within the range of C. oculatus showed that, with only one exception, there were no shared haplotypes between archipelagoes. This result suggests it may be possible to determine the provenence of intercepted specimens, providing further information regarding potential invasion pathways. A degree of geographic structuring was also present within C. o. gilloglyi, being separated into a western clade found in Fiji and Rotuma and an eastern clade distributed from the Kermadec Islands and Tonga to French Polynesia. This separation was most profound in COI data, with a mean pairwise distance between the clades of 7%. ITS2 data also demonstrates a degree of differentiation between the two clades, based on differences in the insertions and deletions between the clades. The variability in the shape and colour of the elytral pattern of C. oculatus was also investigated. Colour was quantified using a method based on Red-Green-Blue (RGB) colour values derived from digital photographs, while an outline analysis of the elytral pattern was conducted using elliptic Fourier analysis (EFA). Principal Components Analysis of the RGB values and EFA coefficients showed no clear separation between subspecies, nor were any trends correlated with host fruit or collection localities. Variation at all levels and all measures studied in this thesis show that this geographic region and this genus of beetles offer intruiging insights into speciation, biogeography and biological invasions. There is much scope for further research on the causes and consequences of this variation and the lives of these interesting insects.
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32

Guichard, Sylvain. "Modelling the proximal source of intercepted exotic insects." Lincoln University, 2009. http://hdl.handle.net/10182/1472.

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Biological invasions are major threats to any nation’s economy and biodiversity. To detect new biological incursions of some species biosecurity agencies deploy pheromone sentinel traps for targeted species at high risk sites such as airports, seaports and transitional facilities. A good example is the gypsy moth surveillance program in New Zealand. Following the detection of an incursion by an unwanted organism, ground-based searches to locate the source can be very expensive, but are essential to identify the introduction pathway and to increase the chances of success eradicating the unwanted organism. In such circumstances, the possibility of better targeting the search for the source of the incursion using a modelling approach is worthy of investigation A stochastic mechanistic model to hindcast moth flight from a recapture location to the release location was developed based on insect behaviour in response to wind and pheromones. The model was composed of two main processes, 1) downwind dispersal, assumed to result from an appetitive behaviour, indicated by an analysis of a previous mark-release-recapture experiment on painted apple moth (Teia anartoides, Walker) and, 2) anemotaxic dispersal inspired by pheromone anemotaxis theory but up-scaled from a fine-scaled behaviour model to a 2 m scale. A genetic algorithm was used to fit some model parameters. A specialised fitness function was developed to allow the genetic algorithm to identify parameters that resulted in models that reflected both the spread and density patterns in the trapping data. The resulting function allowed the stochastic model results to be compared with the inherently stochastic trapping data. The resulting individual based model simulates the spatio-temporal dispersal pattern of painted apple moth recorded during a previous mark-release-recapture experiment. While the proposed model is shown to have limitations with respect to accuracy and precision it is also demonstrated to greatly improve biosecurity incursion response capability, by more efficient targeting of search effort for the proximal source of an incursion.
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33

Hughey, Kenneth F. D. "Hydrological factors influencing the ecology of riverbed breeding birds on the plains' reaches of Canterbury's braided rivers." Lincoln College, University of Canterbury, 1985. http://hdl.handle.net/10182/1639.

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The wide, unstable, braided riverbeds of the eastern South Island, New Zealand, have been inhabited by a diverse avifauna. Several species including the wrybill breed only on these rivers. Use is restricted mainly to the breeding season from September to December, so this was the critical study period. Previous, behaviourally oriented studies have occurred mainly in the high country catchments where habitat modification is slight. However, substantial bird numbers also occur on lowland riverbeds. These areas are subject to existing or planned water developments which may have negative impacts on the conservation of these habitats and bird species. The principal goal of this study was to add to the information necessary to conserve lowland riverbed habitat within multiple use planning strategies. Specific objectives associated with assessing breeding and feeding requirements were therefore hydrologically oriented. Study areas were chosen on the lower Rakaia and lower Ashley rivers. Both are braided but have markedly different flow regimes. The Rakaia is snowfed and has peak flows occurring during the breeding season. The Ashley is primarily rainfed and has a declining breeding season flow regime. Wrybills, black-fronted terns, banded dotterels, South Island pied oystercatchers, and pied stilts breed in these areas. The first two of these were selected as indicator species. It was assumed that because of their restricted habitat needs, flow requirements recommended to meet their needs would also meet those of most other species. Banded dotterels were also studied because of their close taxonomic relationship and overlapping distribution with wrybills. South Island pied oystercatchers and pied stilts were chosen to check the validity of the approach. Breeding, nest site requirements, microhabitat preferences for foraging, diets, home ranges and food supply were studied. Wrybill time-budgets were examined, and the incremental approach to impact assessment was applied to wrybill foraging needs. Breeding success for all species was dependent on the flow regime. In 1982 wrybill fledging success was moderate on the Rakaia, whereas in 1983 it was very low. Conversely, in both years fledging success was very high on the Ashley. This variability resulted from serious flooding on the Rakaia in 1983 which effected all species. Wrybills have nest site characteristics most closely approximating a habitat specialist, while the other species should be considered habitat generalists. Nests are generally close to water, near minor braids, and on non-vegetated shingle substrates. On average there is a higher chance of nests being flooded on the Rakaia than on the Ashley where predation is more likely to reduce nesting success. Vegetation encroachment threatens nest site provision and floods are presently the only natural regular of exotic plants such as lupin. Banded dotterel home ranges were significantly smaller than wrybills, and on an intra-specific basis were smaller on the Ashley. A correlation existed between home range size and habitat quality, so that small wrybill home ranges were dominated by the occurrence of productive minor braids, and larger ones by less productive major channels. Time-budgets provided further insights into the influence of hydrological factors on wrybill ecology. Wrybill time-budgets appear to be inflexible because a high proportion of time is devoted to foraging, with relatively little time available for other activities. Resource depression on the Rakaia in 1983 lessened the chances for wrybills to breed successfully because sufficient food could not be gathered to provide for breeding energy needs. This did not occur on the Ashley River where flows were generally more stable. From a management viewpoint, development strategies which lead to greater flow fluctuations will have a detrimental impact on wrybills. The foraging patterns for all species except black-fronted terns were examined. There was a general preference for aquatic habitats, particularly those associated with minor braids and disconnected pools. Depth and substrate use were studied in detail for wrybills and banded dotterels. Wrybills displayed consistent use patterns between rivers, which reflected specialisation in habitat use. Banded dotterel habitat use varied considerably. Diet was studied by faecal analysis. Both wrybills and banded dotterels fed on invertebrates of aquatic and terrestrial origin. For wrybills it was noticeable that Ephemeroptera larvae did not dominate the diet as had previously been reported for high country catchments. Coleoptera, Hemiptera, and Ephemeroptera were important on the Rakaia with Trichoptera replacing Ephemeroptera larvae on the Ashley. Banded dotterels were more reliant on Coleoptera and Hemiptera on both rivers. Pitfall trapping results showed that terrestrial invertebrate availability was dependent on the proximity of water. Fewer floods on the Ashley led to a more consistent food supply on that river. This helps explain the greater bird density on this river. Severe flooding in 1983 appeared to seriously depress aquatic invertebrate densities on the Rakaia. The incremental approach to impact assessment was applied to wrybill foraging requirements. Depth, substrate, and water velocity preferences were included within a weighted usable area model already developed for fisheries use on the Rakaia River. Over the range of median to low flows studied, weighted usable area increased with declining discharge. A simplified usable width approach was applied to a highly braided section of the Ashley River. Here, usable width declined with falling discharges. This inter-basin difference could be explained with reference to the braiding pattern of each river. The main study objectives were achieved, but the indicator species management approach was of limited value in areas other than nest site requirements. Pied stilts and South Island pied oystercatchers fed at greater depths than wrybills, and often used different microhabitats. However, for foraging, wrybills need appeared adequate indicators of banded dotterel requirements.
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34

Cripps, M. G. "Influence of natural enemies on Cirsium arvense — a biogeographic perspective." Lincoln University, 2009. http://hdl.handle.net/10182/1411.

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Cirsium arvense (L.) Scop. (Californian, Canada, or creeping thistle) is an exotic perennial herb indigenous to Eurasia that successfully established in New Zealand (NZ) approximately 130 years ago. Presently, C. arvense is considered one of the worst invasive weeds in NZ arable and pastoral productions systems. The mechanism most commonly invoked to explain the apparent increased vigour of introduced weeds is release from natural enemies. The enemy release hypothesis (ERH) predicts that plants in an introduced range should experience reduced herbivory, particularly from specialists, and that release from this natural enemy pressure facilitates increased plant performance in the introduced range. In 2007 broad surveys were carried out in NZ and central Europe in order to quantify and compare growth characteristics of C. arvense in its native vs. introduced range. Additionally, permanent field plots were established in NZ and Europe where natural enemies were excluded with the use of insecticide and fungicide applications, and compared with controls (ambient natural enemy pressure). The impact of the specialist leaf-feeding beetle, Cassida rubiginosa Müller, which was recently released in NZ as a biological control agent against thistles, was also assessed. From the field surveys, significantly more endophagous herbivory was present in the native range compared to the introduced range, as predicted by the ERH. Endophagous herbivory in NZ was solely from the capitulum-feeding weevil, Rhinocyllus conicus (Frölich), and was only found in the North Island surveys. No stem mining attack was found anywhere in NZ. The proportion of shoots attacked by the specialised rust pathogen, Puccinia punctiformis (Str.) Röhl., was similar in both the native and introduced ranges. Interestingly, this has casted doubt on the idea that stem-mining vectors, such as Ceratapion onopordi Kirby, are important for transmission of the rust pathogen. Contrary to the ERH, there were no significant difference in plant performance between the native and introduced ranges, or differences could be explained by simple climatic factors. Climate tended to be more favourable for growth of C. arvense in NZ. In the permanent field plots in the native range, population growth of C. arvense was significantly greater where natural enemies were excluded, suggesting that insect herbivores and pathogens might have a regulating influence on the population growth of this plant. Furthermore, the probability of shoots transitioning to the reproductive growth stage was enhanced when insect herbivores were excluded, indicating that natural enemies might influence plant development. The biological control agent C. rubiginosa reduced the growth of C. arvense, although the impact of this herbivore was minimal in comparison to interspecific plant competition. Thus, although there is reduced specialist natural enemy pressure in NZ, the growth of C. arvense is not significantly different from in its native range. Nevertheless, there is some evidence that natural enemies in the native range might have a regulating influence on the population dynamics of the plant, and that the specialist herbivore, C. rubiginosa, can impact the plant in certain conditions.
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35

Troup, Christina. "Foraging strategies of Southern Royal Albatrosses, Diomedea epomophora, Campbell Island during incubation." Lincoln University, 2004. http://hdl.handle.net/10182/1273.

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Among the species of Diomedea albatrosses, diverse foraging strategies during breeding have been described, indicating species differences in foraging ecology and behaviour. Foraging strategies of Southern Royal Albatrosses, Diomedea epomophora (SRA) breeding on Campbell Island were studied in January – early February 1999 during the latter half of incubation. Movements and activity of ten birds were monitored using satellite transmitters and wet-dry activity recorders. Three birds from a pilot tracking study in February 1997 were also included in some analyses. Foraging strategies, zones used, factors influencing the duration of foraging trips, and the influence of wind conditions were investigated. Foraging activity took place at sites with bathymetric characteristics associated with high productivity: outer shelf and shelf-break zones, with a concentration of activity on a shelf contour south of the Snares Islands. This is in contrast to Wandering (D. exulans) and Gibson’s (D. gibsoni) albatrosses, typically deep oceanic foragers, but is similar to Northern Royal Albatross (D. sanfordi). The maximum distance of foraging trips from the colony was 1250 kilometres (mean 584 +351(SD)). This was closer than for incubating Wandering and Gibson’s Albatrosses but more distant than for Northern Royal Albatross from the Otago Peninsula. The mean duration of 77 foraging trips from 52 nests was 10.11 days for females and 8.76 for males (ns). Foraging trips became shorter as incubation progressed. Foraging trips were shorter, but not significantly so, when the median wind speed throughout the foraging trip was higher. No significant relationship was found between bird mass and duration of foraging trips. The mean cumulative distance flown by the ten birds tracked in 1999 was 4262 km + 1318 (SD). Eight of the ten SRA employed a ‘commute, forage, commute’ foraging strategy, and the other two alternated short bouts of commuting and foraging. Commuting phases were characterised by rapid directional flight with a straight-line distance (range) of 180 km to 800 km between positions 24 hours apart. Foraging phases were characterised by a range of less than 180 km per 24 hour interval and frequent tight turns. Displacement rate between successive uplinks was significantly higher during commuting phases (28.6 kph + 1.93 SE) than foraging phases (15.1 kph + 1.4 SE). Wind strength and direction influenced the timing of the return commute to the colony. SRA covered greater distances at more favourable wind angles relative to flight track (broad reach and close reach) than in head, tail or direct side winds. Birds of low mass (< 8kg) made fewer landings in winds above 40 kph than in lighter winds, whereas heavier birds had a similar level of landing activity across all wind speed bands. One bird was delayed for several days by light winds, and another flew off course during strong winds. Two birds exploited the same window of wind conditions to return to the colony, each flying a similar course in both timing and route. These results define the foraging strategies of SRA during incubation, and demonstrate the influence of wind conditions and other factors on the overall duration of foraging trips and on the timing of commuting and foraging phases.
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36

Fuller, Grace Anne. "The Night Shift: Lighting and Nocturnal Strepsirrhine Care in Zoos." Case Western Reserve University School of Graduate Studies / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=case1384463090.

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37

Simeonidis, Andrew. "Development of a mass rearing technique for the Tasmanian brown lacewing, Micromus tasmaniae Walker." Lincoln University, 1995. http://hdl.handle.net/10182/1302.

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Aphids are one of the most important insect pests of greenhouse crops yet to be controlled by biological means. Broad spectrum chemical control is becoming increasingly difficult to use in integrated pest management programmes, therefore, there is a need for a suitable biocontrol agent to be mass reared and released. The Tasmanian brown lacewing, Micromus tasmaniae Walker is an aphid predator that is found commonly throughout Australasia and has suitable characteristics that make it a candidate for mass rearing. A technique for rearing M. tasmaniae was developed. Eggs of M. tasmaniae were reared in batches of 50, 100 and 200 in 20 litre clear plastic containers. The oat aphid, Rhopalosiphum padi L. was fed to the larvae. The results revealed that the highest initial egg density (200 eggs per container) produced the cheapest adults at 22 cents per adult. However, mass rearing adults was considered not practical because of the high production cost, although, mass production of eggs is considered to be economically viable. The cost of producing one egg was 0.015 cents. M tasmaniae was maintained in mass culture for six generations. Simple experiments were carried out to monitor the quality of laboratory-reared insects. The 'wild' insect was used as a quality standard and comparisons with laboratory-reared insect populations were made. The fecundity, development rates and tolerance to pirimicarb, a carbamate insecticide, were determined. Fecundity was found to decline with successive generations in mass culture. The lacewing development experiment indicated that larval stages of each generation suffered the highest mortality rate and that between 35-45% of individuals emerged as adults. The tolerance of adults to pirimicarb did not alter over five generations. Recommendations for improving the mass rearing of M. tasmaniae are discussed.
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38

Schmechel, Frances A. "Aspects of habitat selection, population dynamics, and breeding biology in the endangered Chatham Island oystercatcher (Haematopus chathamensis)." Lincoln University, 2001. http://hdl.handle.net/10182/1814.

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In the late 1980s the endangered Chatham Island oystercatcher (Haematopus chathamensis) (CIO) was estimated at less than 110 individuals. Endemic to the Chatham Islands, New Zealand, it was feared to be declining and, based on existing productivity estimates, in danger of extinction within 50-70 years. These declines were thought to be caused by numerous changes since the arrival of humans, including the introduction of several terrestrial predators, the establishment of marram grass (Ammophila arenaria) which changes dune profiles, and increased disturbance along the coastline. The New Zealand Department of Conservation has undertaken recovery planning and conservation management to increase CIO numbers since the late 1980s. Recovery planning raised some key research questions concerning the population dynamics, habitat selection, and breeding biology of Chatham Island oystercatcher (CIO), and the critical factors currently limiting the population. The objectives of this study were to collect and interpret data on: 1) population size, trends, and distribution across the Chathams, 2) basic breeding parameters, 3) recruitment and mortality rates, 4) habitat selection at the general, territorial and nest-site levels, 5) habitat factors that are correlated with territory quality, and 6) cues that elicit territorial behaviour in CIO.
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39

Travis, Georgia-Rose. "Boat preference and stress behaviour of Hector's dolphin in response to tour boat interactions." Diss., Lincoln University, 2008. http://hdl.handle.net/10182/303.

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Dolphins are increasingly coming into contact with humans, particularly where tourism is involved. It has been assumed that such contact causes chronic stress on dolphin populations. This study examined relatively naive populations of Hector's dolphins and their interaction with various watercrafts. Dolphins in New Zealand have been observed using theodolites and boat-based observations over the last two decades, particularly on the east side of the South Island at Akaroa, which is situated on the coast line of Banks Peninsula. This research was undertaken using shore-based theodolite tracking to observe boat activity around the coast of Lyttelton and Timaru and their associated Harbours. Observations were made mostly over two periods each of six months duration and included the months October through to March during the years 2000-2001 and 2001-2002. Observations made during a third period in 2005 were also incorporated for some of the analyses. Field investigations using a theodolite included more than 376 hours/site/season and recorded dolphin behaviour both with and without the presence of tour boats. Of primary interest were the tours, which ran regular trips to observe Cephalorhynchus hectori in their natural habitat. Hector's dolphins at both Lyttelton and Timaru were consistently observed with particular boat types and not with other types of water craft. Dolphins at Timaru exhibited a greater range of behaviours than those at Lyttelton. Stress-related behaviours such as an increase in swimming speed to open ocean and grouping behaviour were only observed in the presence of boats. Other potential stress behaviours, such as head slaps and repeated tail slaps, were only performed in the absence of boats. Observations implied that some generic dolphin behaviours, which often indicate stressed individuals may not apply to Hector's dolphins, and therefore question the assumption that all dolphin species behave in similar ways. We suggest that low-level tourist boat activity is not placing undue stress on the population. In addition to theodolite observations, tour boat based observations of Hector's dolphin were undertaken and behaviour at each site recorded for a focal animal. Tour boat-based observations concentrated on determining any preference to bow, stern, portside and starboard sides of the vessel. Dolphins consistently showed a preference in direction of approach and departure from tour vessels with a strong tendancy to the bow of the boat, and least with the stern. These results were similar irrespective of site or vessel. Behaviour data were also collected from tour boat vessels over 48 trips/season/site and the data divided into transitional behaviour groups, which included stress behaviours, association / interaction behaviour and neutral behaviour. Behavioural count and time data were collected to reflect the number of times and duration of behaviour occurrence, particularly in relation to transitional behaviours. Determining the presence of stress in Hector's dolphins varied between the data sets and indicated that time is a necessary factor when attempting to determine whether an individual or a general population is genuinely stressed. Quadrant preference and swimming direction in relation to the Black Cat were observed over six years, and both count and time data were collected with regard to behaviour. The results were consistent with preference in quadrant being expressed towards the bow of the boat and least with the stern. The count data suggested no significant impact on Hector's dolphin behaviour in the presence of the Black Cat over time, where time data indicated there was a transition over the years from neutral behaviour in the second year of tour boat activity, to positive behaviour in the third year of boat-activity and finally avoidance behaviour in the seventh year of tour boat activity at Lyttelton Harbour in response to the presence of the Black Cat.
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40

Bowie, Mike H. "Evaluation of image analysis for studing mite behaviour." Lincoln University, 1996. http://hdl.handle.net/10182/1056.

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The aim of this study was to investigate the usefulness of image analysis for studying mite behaviour. Image analysis was used to convert video recordings of mites' locomotory behaviour into a series of x,y coordinates that, when joined, closely resemble the paths of mites. The coordinates were also used to calculate walking speed, direction of travel, turning frequency, turn bias and tortuosity. Two experimental arenas were developed and used to study the movement of three mite species: 1) a leaf disc arena for two-spotted spider mite, Tetranychus urticae Koch and European red mite, Panonychus ulmi (Koch); and 2), a cover-slip/tack-trap arena for Typhlodromus pyri Scheuten. Two-spotted spider mite exhibited a change in locomotory behaviour through a 48 minute period. Mites exhibited a significant decline in distance travelled, whereas the mean stationary time (per four minute interval) more than doubled, and the duration of stationary events increased steadily over the same period. A reduction in sampling frequency of mite coordinates from one per second to one every two seconds and every four seconds produced a 5% and 12% 'loss' in path length respectively. Sample period length was shown to greatly influence the results produced for some of the mean parameters calculated, however, a reduction in sample length from 3000 to 1500 coordinates was not considered to cause a major loss in information. The influence of the inherent mite movement could not be ignored and made it difficult to make decisions on the 'best' sample length to use. Some strong correlations were found between parameters used to analyse mite locomotory behaviour. In particular, arithmetic mean vector length, speed, total stationary time and total distance travelled were significantly correlated with each other. Mean angular deviation and weighted mean vector length, which both measure the degree of clustering around the mean heading angle, were strongly negatively correlated. Parameters which differentiated between 'straight' and 'tortuous' mite movement were found to be mean meander, absolute mean turn and fractal dimensions. Mean meander was thought to be the most 'powerful', while coefficient of a straight line, a commonly used parameter for measuring tortuosity, did not significantly differentiate between the two different behaviours. Frequency distributions of turns and standard deviations of the three mite species were very similar. All three species had a slight bias to turning right (clockwise) rather than to the left (counter-clockwise) and for each species certain angles occurred more often than would be expected in a 'perfect' normal distribution. A similar pattern also occurred with the frequency distribution of two-spotted spider mite heading angles, in that angles which were expected to occur more often, did not, and vice versa. The potential to use saturated salt solutions to control relative humidity on the arena was` demonstrated and indicated that relative humidity is likely to have an important influence on mite behaviour. Two-spotted spider mites appeared to move more quickly in an attempt to escape the unfavourable, extreme (10% and 95% R.H. at 25°C) moisture conditions. All three mite species displayed a characteristic edge-walking behaviour around the arenas. However, when 'edge' and 'non-edge' behaviours were compared, mean meander was the only parameter (of the parameters tested) which gave a significant difference. Behavioural responses of European red mite and T. pyri to sub-lethal (field rate) esfenvalerate were investigated and the results indicated that these mites did not seek the unsprayed halves of the arenas during the first 48 minutes. However, significant differences in most behavioural parameters to esfenvalerate residues were found with European red mite when whole arenas were compared. Image analysis is an extremely useful research tool for studying mite behaviour because of its ability to measure many parameters quickly. Careful choice of the environmental conditions, the sampling framework, and interpretation of data is essential for meaningful results.
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41

Barron, M. C. "Population ecology of the red admiral butterfly (Bassaris gonerilla) and the effects of non-target parasitism by Pteromalus puparum." Lincoln University, 2004. http://hdl.handle.net/10182/1763.

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There is anecdotal evidence that populations of the New Zealand endemic red admiral butterfly Bassaris gonerilla (F.) have declined since the early 1900s. This decline has been associated with the introduction of the generalist pupal parasitoids Pteromalus puparum (L.) and Echthromorpha intricatoria (F.). The former was deliberately introduced for the biological control of the cabbage white butterfly (Pieris rapae (L.)); the latter is an adventitious arrival from Australia. The objective of this thesis was to quantify, using population models, the effect that P. puparum is having on B. gonerilla abundance. Population monitoring and a phenology model (based on temperature-related development rates) indicated that B. gonerilla has two full generations and one partial generation per summer in the Banks Peninsula region of New Zealand. B. gonerilla abundance was greatly reduced in drought summers, which was probably due to the negative effects of drought on the quality and quantity of the larval host plant Urtica ferox Forst. A life table study showed that egg parasitism by the unidentified scelionid Telenomus sp. was the largest mortality factor for the pre-imaginal stages of B. gonerilla, followed by "disappearance" mortality (predation and dispersal) in the larval stages. Pupal mortality due to P. puparum was lower compared with that caused by E. intricatoria, with 1-19% and 20-30% of pupae being parasitised by P. puparum and E. intricatoria, respectively. Collection of B. gonerilla pupae from the Christchurch, Dunedin and Wellington areas confirmed higher rates of percentage parasitism by E. intricatoria. B. gonerilla collected from the Banks Peninsula had a 50: 50 sex ratio and lifetime fecundity was estimated in the laboratory as 312 eggs per female. There was no evidence of density-dependent parasitism of B. gonerilla pupae by P. puparum in the field, although there was a significant positive relationship between life table estimates of E. intricatoria parasitism and B. gonerilla pupal abundance. Larval dispersal from the host plant showed a positive relationship with larval instar but no relationship with larval density. Rates of change in B. gonerilla adult abundance between generations within a year showed evidence of density dependence, and this negative feedback was stronger in a drought year. A discrete-time model for B. gonerilla population dynamics was constructed which had two summer generations per year and a partial overwintering generation. The model showed that the presence of this overwintering generation provides a temporal refuge from high levels of E. intricatoria parasitism. Removal of parasitoid mortality from the model suggested that P. puparum was suppressing B. Gonerilla populations on the Banks Peninsula by 5% and E. intricatoria by 30%. An important assumption of the model was that parasitism rates were independent of B. gonerilla density. This assumption appears valid for P. puparum parasitism, but may not be valid for E. intricatoria; therefore the estimated suppression levels due to this adventive parasitoid should be viewed with some caution. It is too soon to generalise on what determines the magnitude of non-target effects by arthropod biocontrol agents, this being only the second study to quantify effects at a population level. However, in this case retrospective analysis has shown that the impact of non-target parasitism by P. puparum on B. gonerilla abundance has been small. There is anecdotal evidence that populations of the New Zealand endemic red admiral butterfly Bassaris gonerilla (F.) have declined since the early 1900s. This decline has been associated with the introduction of the generalist pupal parasitoids Pteromalus puparum (L.) and Echthromorpha intricatoria (F.). The former was deliberately introduced for the biological control of the cabbage white butterfly (Pieris rapae (L.)); the latter is an adventitious arrival from Australia. The objective of this thesis was to quantify, using population models, the effect that P. puparum is having on B. gonerilla abundance. Population monitoring and a phenology model (based on temperature-related development rates) indicated that B. gonerilla has two full generations and one partial generation per summer in the Banks Peninsula region of New Zealand. B. gonerilla abundance was greatly reduced in drought summers, which was probably due to the negative effects of drought on the quality and quantity of the larval host plant Urtica ferox Forst.. A life table study showed that egg parasitism by the unidentified scelionid Telenomus sp. was the largest mortality factor for the pre-imaginal stages of B. gonerilla, followed by "disappearance" mortality (predation and dispersal) in the larval stages. Pupal mortality due to P. puparum was lower compared with that caused by E. intricatoria, with 1-19% and 20-30% of pupae being parasitised by P. puparum and E. intricatoria, respectively. Collection of B. gonerilla pupae from the Christchurch, Dunedin and Wellington areas confirmed higher rates of percentage parasitism by E. intricatoria. B. gonerilla collected from the Banks Peninsula had a 50: 50 sex ratio and lifetime fecundity was estimated in the laboratory as 312 eggs per female. There was no evidence of density-dependent parasitism of B. gonerilla pupae by P. puparum in the field, although there was a significant positive relationship between life table estimates of E. intricatoria parasitism and B. gonerilla pupal abundance. Larval dispersal from the host plant showed a positive relationship with larval instar but no relationship with larval density. Rates of change in B. gonerilla adult abundance between generations within a year showed evidence of density dependence, and this negative feedback was stronger in a drought year. A discrete-time model for B. gonerilla population dynamics was constructed which had two summer generations per year and a partial overwintering generation. The model showed that the presence of this overwintering generation provides a temporal refuge from high levels of E. intricatoria parasitism. Removal of parasitoid mortality from the model suggested that P. puparum was suppressing B. Gonerilla populations on the Banks Peninsula by 5% and E. intricatoria by 30%. An important assumption of the model was that parasitism rates were independent of B. gonerilla density. This assumption appears valid for P. puparum parasitism, but may not be valid for E. intricatoria; therefore the estimated suppression levels due to this adventive parasitoid should be viewed with some caution. It is too soon to generalise on what determines the magnitude of non-target effects by arthropod biocontrol agents, this being only the second study to quantify effects at a population level. However, in this case retrospective analysis has shown that the impact of non-target parasitism by P. puparum on B. gonerilla abundance has been small.
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42

Wragg, Graham. "The comparative biology of Fluttering shearwater and Hutton's shearwater and their relationship to other shearwater species." Lincoln College, University of Canterbury, 1985. http://hdl.handle.net/10182/1635.

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The discovery and taxonomic history of fluttering shearwater (Puffinus gavia (Forster) and Hutton's shearwater (Puffinus huttoni Mathews) are reviewed. Taxonomic theory, where appropriate to this thesis, is discussed. The external morphology of P. gavia and P. huttoni is compared. No single external measurement or plumage character separates more than 60% of birds examined. The best system of identification is to compare the ratio of different body parts within an individual bird. The distribution of P. gavia and P. huttoni is compared. Hutton's shearwater feeds further out to sea and it is believed to be a migrant species wintering in north west Australian waters. The fluttering shearwater is believed to be a semi-migrant species with only the juveniles spending time in south east Australia. The red cell enzymes of P. gavia, P. huttoni and P. griseus are compared. There are differences in two esterase loci between gavia and huttoni, while P. griseus is more distantly related. Nei's genetic identity values are calculated. The systematic value of electrophoretic data is discussed. The relationship of an undescribed subfossil shearwater to P. gavia and P. huttoni is discussed. An outgroup analysis to other shearwater species is carried out according to phylogenetic (cladistic) theory. The subfossil shearwater is most closely related to the fluttering shearwater, and these two form a sister group to Hutton's shearwater. These three species are a sister group of P. opisthomelas. The relationship between the many P. assimilis subspecies, the black-backed Manx shearwaters, and the gavia, huttoni and opisthomelas group was not resolved. Puffinus nativitatis is more closely related to the Manx and the little shearwaters than to the P. griseus, P. tenuirostris group.
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43

Santos, Wellington Bittencourt. "Análise de livros didáticos e validação de sequência didática sobre pluralismo de processos e evo-devo no contexto do ensino de Zoologia de Vertebrados." Universidade Federal da Bahia, 2011. http://repositorio.ufba.br/ri/handle/ri/14548.

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Fapesb
Este artigo relata os resultados de uma análise de conteúdo comparativa de três livros didáticos de biologia evolutiva e três livros didáticos de zoologia de vertebrados, muitos adotados em ementas de cursos de formação superior de biologia de diversas universidades de países de línguas latinas e anglo-saxônicas. Através de uma análise documental quali-quantitativa dos livros didáticos, realizada através de metodologia de análise de conteúdo, empreendemos uma investigação sobre a abordagem e recontextualização de conteúdos relativos à biologia evolutiva do desenvolvimento (evo-devo) e ao pluralismo de processos presentes nos livros selecionados. Com base nesta investigação, buscamos responder à seguinte pergunta: em que medida e de que maneira os referidos conteúdos, relacionados a avanços importantes que tiveram lugar na biologia evolutiva das últimas duas décadas, estão sendo recontextualizados em livros didáticos de evolução e nas discussões sobre evolução presentes em livros didáticos de zoologia de vertebrados? Os achados deste estudo indicam que os livros de evolução se encontram ainda em uma fase inicial de recontextualização dos conteúdos relativos ao pluralismo de processos e, assim, ao que tem sido denominada a síntese estendida no campo da biologia evolutiva. Contudo, eles se encontram em um estágio mais avançado de recontextualização que os livros de zoologia de vertebrados analisados, nos quais foi observada uma diversidade substancialmente menor de mecanismos evolutivos, com uma grande ênfase apenas sobre a seleção natural. Estes achados não são surpreendentes, uma vez que a idéia de uma síntese estendida ainda não está bem estabelecida na própria biologia evolutiva. No que diz respeito aos conteúdos relativos à evo-devo, foi constatado um nível mais significativo de recontextualização nos livros didáticos de ambos os campos de estudo, o que mostra que ao menos parte do conteúdo da chamada síntese estendida já alcançou o ensino superior de biologia.
Salvador
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44

Schwarzer, Julia [Verfasser]. "Cichlids of the lower Congo River - a new model system in speciation research? / Julia Schwarzer." Bonn : Universitäts- und Landesbibliothek Bonn, 2012. http://d-nb.info/1044970634/34.

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45

Martins, Luciana Conrado. "A relação museu/escola: teoria e prática educacionais nas visitas escolares ao Museu de Zoologia da USP." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/48/48134/tde-19062007-152057/.

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Esta pesquisa versa sobre as relações museu/escola. Identifica e confronta os discursos e as práticas educacionais dos profissionais envolvidos. Inserido em uma perspectiva qualitativa de pesquisa em educação, o estudo analisa as práticas presentes na visita de escolas ao Museu de Zoologia da Universidade de São Paulo. Considera-se que os educadores de museus são portadores de um conhecimento empírico e teórico que é, em grande medida, o responsável pela normatização das atividades educacionais da instituição onde estão inseridos. Outros fatores tais como a história da instituição, sua estrutura administrativa e o contexto social do qual faz parte também são relevantes para o entendimento do campo analisado. São esses aspectos os que vão determinar qual é o discurso dos profissionais de educação responsáveis pela ação educativa de um museu, frente às práticas pedagógicas por eles estabelecidas, passo necessário para compreensão do objeto de estudo. Por outro lado, considera-se também que os professores das escolas são portadores de uma concepção própria a respeito do museu. Qual é essa concepção? Quais são as expectativas destes profissionais que enfrentam inúmeras dificuldades para levarem seus alunos a uma instituição cuja linguagem e conteúdo não lhes são familiares? Suas expectativas são cumpridas durante a visitação? Entender esse universo passa pela observação das práticas desses profissionais quando em contato com a instituição museal. A fim de responder esses questionamentos, optou-se pela confrontação das expectativas desses profissionais (professores e educadores do Museu) com a sua prática em um momento determinado: a visita das escolas ao Museu. Essa escolha baseou-se na verificação de que a visita é o momento onde se efetivam/confrontam as intenções a respeito da prática pedagógica dentro de uma exposição de museu. A escolha do Museu de Zoologia da Universidade de São Paulo, e posterior pesquisa empírica nas suas dependências, trouxe à tona outros questionamentos, acerca do papel da educação dentro de uma instituição museológica, voltada historicamente a pesquisa em Zoologia. Para fundamentação das análises propostas foi utilizado o referencial oriundo das pesquisas de educação e pesquisas de público, feitas em museus. Em termos gerais, constatou-se que professores e educadores de Museu têm expectativas semelhantes a respeito do potencial pedagógico das exposições museais. Entretanto, as escolas continuam buscando os museus sem atentar para as especificidades educacionais desses espaços, fazendo com que a visita seja um acontecimento isolado na vida escolar dos estudantes. Por outro lado, o Museu de Zoologia, agrega uma série de fatores que contribuem para não otimização de sua relação com as instituições escolares. A constatação desses problemas aponta a necessidade de construção de uma parceria a ser realizada institucionalmente entre museus e escolas, ou seja, apoiada por todas as instâncias que as compõem, e não dependente apenas de alguns poucos profissionais interessados.
This research treats of the museum/school relation. Identifies and confronts the educational discourses and the practices of the involved professionals. Inserted on a qualitative view on education, this study analyses the present practices on school visits to the Museum of Zoology of University of São Paulo. It is considered that the museum\'s educators carry an empirical and theoretical knowledge, which is responsible for the normative conduction of the educational activities on the institution where they are involved. Other factors such as the institution\'s history, the administration\'s structure and the social context are relevant for the comprehension of the analysis field. Those are the aspects that are going to determine what is the discourse of the professionals of education who are responsible for educational actions of the museum, facing their pedagogical practises, necessary step to the comprehension of the object. On the other hand, it\'s as well considered that schools teachers have their own conception regarding the museum. What is this conception? What are the expectancies of those professionals, who confront innumerable difficulties to take their pupils to an institution whose language and contents are not familiar to them? Are their expectancies fulfilled during visitation? To understand the universe means to observe the practices of those professionals in contact with the museum institution. Aiming to answer those questions, the confrontation of the professional\'s expectancies (teachers and museum\'s educators) with their practices in a specific moment: the schools visitations to the Museum. This choice is based on the verification that the visit is the moment when the intentions, regarding to the pedagogical practice, are accomplished/confronted in a museum exposition. The choice for the University of São Paulo\'s Museum of Zoology, and posterior empirical research inside the museum, emerged other questions concerning the educational role inside the museological institution, historically dedicated to zoological researches. A referential originating in education researches and public researches, that took place in museums, was used to ground the proposed analysis. It was verified that teachers and museum\'s educators have similar expectancies regarding to the pedagogical potential of museums expositions. However, the schools still attending to museums without being alert to the educational particularities of these places, converting the visit on a isolated event to the school life of the student. On the other hand, the Museum of Zoology, aggregates factors, which contributes to the non-optimisation of its relation with school institutions. The evidencing of those problems indicates the need to enter an institutional partnership between museums and schools, supported by all the instances involved and not only few interested professionals.
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46

Hoang, Thanh V. "TRANSCRIPTIOME ANALYSIS AND EPIGENETIC REGULATION OF OCULAR LENS DEVELOPMENT." Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1478876890292631.

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47

Laubertie, Elsa. "The role of resource subsidies in enhancing biological control of aphids by hoverflies (Diptera: Syrphidae)." Diss., Lincoln University, 2007. http://hdl.handle.net/10182/984.

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In this thesis, experiments were conducted in the laboratory and the field to determine whether the provision of floral resources to hoverflies could enhance the biological control of aphids. The overall aim was to clarify hoverfly behaviour and ecology in an agroecosystem in order to understand the potential of these insects for biocontrol under a conservation biological control (CBC) regime. A preliminary experiment in New Zealand compared the effect of different coloured water-traps on catches of the hoverflies Melanostoma fasciatum (Macquart) and Melangyna novaezelandiae (Macquart). Significantly more individuals were caught in completely yellow traps than in traps with green outer walls and yellow inner walls or in completely green traps. This suggested that if a measure of hoverfly numbers relating to a particular distance along a transect is required, consideration should be given to the ability of hoverflies to detect yellow traps from a distance. The use of traps that are green outside would more accurately reflect the local abundance of hoverflies, as the insect would be likely to see the yellow stimulus only when above or close to the trap. Also, the addition of rose water significantly increased the number of M. fasciatum caught. From a suite of flowering plants chosen for their ability in other studies to increase hoverfly visit frequencies, laboratory experiments were conducted in France to determine the plant’s effectiveness at enhancing Episyrphus balteatus (De Geer) ‘fitness’, and to evaluate whether adult feeding on flowers was related to performance. Phacelia (Phacelia tanacetifolia Bentham cv. Balo), followed by buckwheat (Fagopyrum esculentum Moench cv. Katowase) and coriander (Coriandrum sativum L.) gave the optimal reproductive potential of female E. balteatus. There was no correlation between pollen and nectar consumption, and there was no discernible positive correlation between the quantity of pollen ingested and the resulting female performance. Phacelia and buckwheat were then studied as resource subsidies in the field in New Zealand. The effect of incorporating phacelia or buckwheat in the margins of 5 m x 5 m broccoli plots was tested for hoverfly activity and floral ‘preferences’. Hoverflies which had fed on phacelia and buckwheat pollen were found up to 17.5 m from the floral strips and females of M. fasciatum and M. novaezelandiae consumed more phacelia pollen than that of buckwheat in the field. These results support the choice of phacelia as an ideal floral resource subsidy in crops for enhanced biological control by these New Zealand species. The need for studying hoverfly movement in a large-scale field experiment was apparent from the field studies, so the next experiment was carried out in a field 450 × 270 m and flies were marked via their ingestion of the pollen of phacelia. The focus was on the proportion of flies having consumed the pollen. Although large quantities of pollen were found in some hoverfly guts, most did not contain phacelia pollen and very few were captured at 50 m from phacelia, compared with numbers at the border of the floral strip. A possible explanation was that hoverflies feed on a large variety of pollen species, reducing the relative attraction of phacelia flowers. Another possibility was that hoverflies dispersed from the phacelia away from the crop. Also, pollen digestion rates are likely to be a factor. Finally, a series of experiments was conducted in the field and laboratory to study hoverfly efficacy through oviposition and larval behaviour. In field experiments, female M. fasciatum and M. novaezelandiae laid more eggs where buckwheat patches were larger; however higher oviposition rates did not lead to improved aphid population suppression. In greenhouse experiments, larvae of E. balteatus could initiate a decline in aphid numbers at the predator: prey ratio 1: 8.3, however this control did not persist. Experiments in the laboratory showed that hoverfly larvae became more active and left the system while aphid numbers declined or numbers of larvae increased. This behaviour was caused by two factors: hunger and avoidance of conspecific larvae. Further experiments showed that the avoidance of conspecifics was caused by mutual interference rather than cannibalism. The results of this work highlight the importance of hoverfly dispersal ability. Given the observations of foraging behaviour of females and mutual interference observed between larvae, and the lack of success in CBC by hoverflies in experiments at the crop scale, it is essential to assess the impact of insect predators and parasitoids at a landscape scale.
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48

Murray, Tara J. "Effect of physiological and behavioural characteristics of parasitoids on host specificity testing outcomes and the biological control of Paropsis charybdis." Lincoln University, 2010. http://hdl.handle.net/10182/1558.

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An established host-parasitoid-hyperparasitoid system was used to investigate how the physiological and behavioural characteristics of parasitoids influence the outcomes of laboratory-based host specificity tests. The characteristics of the two pteromalid egg parasitoids, Enoggera nassaui (Girault) and Neopolycystus insectifurax Girault, were assessed and interpreted in regard to the particular host specificity testing methods used and the control of the eucalypt defoliating beetle Paropsis charybdis Stål (Chrysomelidae) in New Zealand. The physiology of N. insectifurax was examined to determine how to increase production of female parasitoids that were physiologically capable and motivated to parasitise P. charybdis eggs in laboratory trials. Neopolycystus insectifurax were found to be more synovigenic than E. nassaui. Provisioning them with honey and host stimuli for three days, and allowing females to parasitise hosts in isolation (i.e. in the absence of competition) was an effective means of achieving these goals. No-choice tests were conducted in Petri dish arenas with the four paropsine beetles established in New Zealand. All four were found to be within the physiological host ranges of E. nassaui and N. insectifurax, but their quality as hosts, as indicated by the percent parasitised and offspring sex ratios, varied. The results of paired choice tests between three of the four species agreed with those of no-choice tests in most instances. However, the host Trachymela catenata (Chapuis), which was parasitised at very low levels by E. nassaui in no-choice tests, was not accepted by that species in paired choice tests. A much stronger preference by N. insectifurax for P. charybdis over T. catenata was recorded in the paired choice test than expected considering the latter was parasitised at a high level in the no-choice test. The presence of the target host in paired choice tests reduced acceptance of lower ranked hosts. Both no-choice and choice tests failed to predict that eggs of the acacia feeding beetle Dicranosterna semipunctata (Chapuis) would not be within the ecological host range of E. nassaui and N. insectifurax. Behavioural observations were made of interspecific competition between E. nassaui and N. insectifurax for access to P. charybdis eggs. Two very different oviposition strategies were identified. Neopolycystus insectifurax were characterised by taking possession of, and aggressively guarding host eggs during and after oviposition. They also appeared to selectively oviposit into host eggs already parasitised by E. nassaui, but did not emerge from significantly more multi-parasitised hosts than E. nassaui. Enoggera nassaui did not engage in contests and fled when approached by N. insectifurax. Although often prohibited from ovipositing by N. insectifurax, E. nassaui were able to locate and begin ovipositing more quickly, and did not remain to guard eggs after oviposition. It is hypothesised that although N. insectifurax have a competitive advantage in a Petri dish arena, E. nassaui may be able to locate and parasitise more host eggs in the field in New Zealand, where competition for hosts in is relatively low. The biology of the newly established encyrtid Baeoanusia albifunicle Girault was assessed. It was confirmed to be a direct obligate hyperparasitoid able to exploit E. nassaui but not N. insectifurax. Field and database surveys found that all three parasitoids have become established in many climatically different parts of New Zealand. Physiological characteristics were identified that may allow B. albifunicle to reduced effective parasitism of P. charybdis by E. nassaui to below 10%. However, the fact that hyperparasitism still prevents P. charybdis larvae from emerging, and that B. albifunicle does not attack N. insectifurax, may preclude any significant impact on the biological control of P. charybdis. Overall, parasitoid ovigeny and behavioural interactions with other parasitoids were recognised as key characteristics having the potential to influence host acceptance in the laboratory and the successful biological control of P. charybdis in the field. It is recommended that such characteristics be considered in the design and implementation of host specificity tests and might best be assessed by conducting behavioural observations during parasitoid colony maintenance and the earliest stages of host specificity testing.
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49

Schulte, Katharina [Verfasser], and Axel [Akademischer Betreuer] Temming. "The monitoring of the spatiotemporal distribution and movement of brown shrimp (Crangon crangon L.) using commercial and scientific research data / Katharina Schulte. Betreuer: Axel Temming." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/1106404858/34.

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50

Schulte, Katharina Verfasser], and Axel [Akademischer Betreuer] [Temming. "The monitoring of the spatiotemporal distribution and movement of brown shrimp (Crangon crangon L.) using commercial and scientific research data / Katharina Schulte. Betreuer: Axel Temming." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2016. http://d-nb.info/1106404858/34.

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