Dissertations / Theses: 'Nestlings'

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Berg, Melanie Dawn. "Yolk androgens and development in American kestrel nestlings." [Boise, Idaho] : Boise State University, 2009. http://scholarworks.boisestate.edu/td/11/.

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Borgia, Lisa. "Factors affecting growth and survival of snowy egret nestlings." FIU Digital Commons, 1999. http://digitalcommons.fiu.edu/etd/1734.

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It is widely believed that wading birds in the Everglades have declined as a result of historic water management practices. I determined growth rates for Snowy Egret (Egretta thula) chicks by assessed the nestling body condition through measurement of body weight and skeletal traits. A growth index was calculated as a residual of body weight regressed on age. A body condition index was calculated as the residual of body weight regressed on a skeletal trait (tarsus). Growth was significantly related to water level and hatch date. Survival rates were calculated to day 14, 21, and 50. Survival to 50 days of age was significantly related to hatch date and order. Survival to 21 days of age was significantly related to water level and hatching order. Survival to 14 days of age was marginally related to hatching order. Growth and survival is greatly influenced by water level and hatch date.

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McCullagh, Melanie Cuchlaine. "Decision-making in zebra finches : parent-offspring communication." Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363783.

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Moe, Børge. "Energy-allocation in avian nestlings facing short-term food shortage." Doctoral thesis, Norwegian University of Science and Technology, Department of Biology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-1662.

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This thesis investigates effects of short-term food shortage on growth, body composition and metabolic development of Pekin ducklings (Anas platyrhynchos domesticus) and European shag nestlings (Phalacrocorax aristotelis), two species representing extremes within the altricial-precocial spectrum. The aims of the thesis were to 1) characterise patterns of growth and development in response to short-term food shortage during early development, 2) examine aspects of energy allocation during these responses with special emphasis on the basal level of energy metabolism, thermoregulatory ability and body composition and 3) investigate the effect of shortterm food shortage on subsequent growth and fledging body size.

Paper III: The original publication is available at www.springerlink.com

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Kilner, Rebecca Mary. "Parental investment in canaries and zebra finches." Thesis, University of Cambridge, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326633.

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Pires, Bárbara Afonso. "Use and effects of aromatic plants in Blue Tit nests." Doctoral thesis, Universidade de Évora, 2020. http://hdl.handle.net/10174/28077.

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Some bird species also incorporate aromatic plants in their nests. To explain this behaviour several hypotheses have been proposed, mainly related to hiding/shading of the nest, but also with regulation of nest water loss and heat rates. In secondary cavity-nesting species like Blue Tits, hypotheses related to reduction of parasite populations and improvement of nestlings’ condition are considered more appropriate to explain this behaviour. These species, because their nests are hidden and because they often reuse the same cavities year after year, are more exposed to higher abundances of parasites, arising mainly from overwintering parasites. This study aims to understand i) how nestlings of secondary cavity-nesting species are affected by parasites present in nests, ii) how aromatic plants are used in Blue Tit (our model species) nests and iii) how that use influences nest features, reproductive parameters and nestling condition. Nestlings of cavity-nesting species are affected by parasites present in nests through close contact with parasites and through parental condition. Parents and nestlings adopt different defence mechanisms to limit and/or alleviate deleterious effects of parasites. Incorporation of specific aromatic plants in Blue Tit nests produced nestlings with longer tarsi but only in large broods. Even when aromatic plants were experimentally incorporated in nests, female Blue Tits found the need to incorporate aromatic plants of their choice, with a very diverse pattern of use, and not always directly related to the availability of these plants in the nests’ vicinities. Significant associations between aromatic plants incorporated in nests by females, nest weight, laying date and reproductive parameters were observed. These results provide new insights on how female Blue Tits use aromatic plants in their nests and how this use is related to nest construction features, reproductive parameters and nestling condition; Resumo: Uso e Efeitos de plantas aromáticas em ninhos de Chapim-azul Algumas aves, além do material que utilizam para construção do ninho, também adicionam plantas aromáticas. Para explicar este comportamento foram propostas várias hipóteses relacionadas com dissimulação/sombra dos ninhos, mas também com regulação da perda de água e níveis de calor. Em aves cavernícolas secundárias, como o Chapim-azul, as hipóteses relacionadas com redução das populações de parasitas e melhoria da condição das crias têm sido valorizadas para explicar este comportamento. Estas espécies, cujos ninhos são abrigados e muitas vezes reutilizados ano após ano, estão mais expostas a maiores abundâncias de parasitas, principalmente dos que fazem a hibernação de inverno nas cavidades. Este estudo pretende compreender i) como as crias de aves cavernícolas são afetadas por parasitas presentes nos ninhos, ii) como as plantas aromáticas são utilizadas em ninhos de Chapim-azul e iii) como essa utilização influencia características dos ninhos, parâmetros reprodutivos e condição das crias. As crias de aves cavernícolas são afetadas por parasitas presentes nos ninhos por contacto direto com esses parasitas, mas também através da condição dos progenitores. Progenitores e crias adotam diferentes mecanismos de defesa para limitar e/ou aliviar os efeitos prejudiciais desses parasitas. A incorporação de plantas aromáticas específicas em ninhos de Chapim-azul produziu crias com maior tarso, mas apenas em ninhadas grandes. Mesmo com suplementação de plantas aromáticas nos ninhos, as fêmeas de Chapim-azul adicionaram plantas escolhidas por si, com um padrão de uso muito diverso, e nem sempre diretamente relacionado com a disponibilidade dessas plantas na área circundante dos ninhos. Foram observadas relações significativas entre plantas aromáticas adicionadas aos ninhos pelas fêmeas, peso dos ninhos, data de postura e parâmetros reprodutivos. Estes resultados fornecem novas perspectivas de como as fêmeas de Chapim-azul utilizam plantas aromáticas nos seus ninhos e de como este uso está relacionado com características dos ninhos, parâmetros reprodutivos e condição das crias.

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Kovatch, Jeffrey J. "Resource allocation to growth and thermoregulation during early development in altricial nestlings." Related electronic resource: Current Research at SU : database of SU dissertations, recent titles available full text, 2008. http://wwwlib.umi.com/cr/syr/main.

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Randa, Jacob G. "Diet and Effects of Environmental Stressors on the Altricial Nestlings of Double-Crested Cormorants (Phalacrocorax Auritus)." Thesis, North Dakota State University, 2014. https://hdl.handle.net/10365/26911.

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Double-crested cormorants (Phalacrocorax auritus) are a common species of altricial waterbird found across much of North America. As a piscivorous colonial waterbird, cormorants are often persecuted due to perceived impacts on fisheries. In this study I examined the diet of cormorant nestlings at five cormorant colonies in central North America to answer two questions: 1) Is nestling diet reflective of opportunistic feeding behavior, thus diminishing the likelihood of negative impacts to the fishery? and 2) How do diet and environmental stressors effect the development of cormorant nestlings? By analyzing the caloric content of nestling diet and quantifying environmental stressors such as endoparasite and ectoparasite loads, I found diet was a significant contributor to structural long bone growth in both the wing and tarsus. Diet analysis also corroborated the long held belief that cormorants have highly variable diets reflective of local fish communities and may vary annually as fish assemblages change.
Voyageurs National Park
Ontario Ministry of Natural Resources
Windels, Steve

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9

Martinovic, Barbara. "Corticosterone and vitamin A concentrations in tree swallow (Tachycineta bicolor) nestlings exposed to environmental contaminants along the St. Lawrence River, Canada and United States of America." Thesis, University of Ottawa (Canada), 2002. http://hdl.handle.net/10393/6253.

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In 1999 and 2000 reproductive success and chemical biomarkers were measured in 16 day old tree swallows (Tachycineta bicolor) collected from nine sites along the St. Lawrence River in Canada and USA. Chicks were collected for analysis of organochlorine pesticides, polychlorinated biphenyls (PCBs), total mercury, polychlorinated dibenzodioxins (PCDDs), and polychlorinated dibenzofurans (PCDFs), and measures of corticosterone response, and vitamin A concentrations. Study sites were located in the vicinity of landfill sites and industrial outfalls in the St. Lawrence River area of concern (AOC). Altered vitamin A metabolism and corticosterone homeostasis in wildlife exposed to contaminants may lead to numerous effects on reproduction, growth, and immune function. Overall these data suggest that current levels of organochlorine contamination may be affecting the hypothalamo-pituitary-adrenal axis and vitamin A levels in environmentally exposed tree swallow nestlings along the St. Lawrence River. (Abstract shortened by UMI.)

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Wink, Judy. "Great horned owl nestling behavior /." Instructions for remote access. Click here to access this electronic resource. Access available to Kutztown University faculty, staff, and students only, 1985. http://www.kutztown.edu/library/services/remote_access.asp.

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Thesis (M.S.)--Kutztown University of Pennsylvania, 1985.
Source: Masters Abstracts International, Volume: 45-06, page: 3047. Typescript. Abstract precedes thesis as preliminary leaves [1-2] Includes bibliographical references (leaves 64-66).

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Feltham, Mark J. "The energetics of nestling birds." Thesis, University of Stirling, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254397.

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Budden, Amber Elizabeth. "Nestling begging in southern grey shrikes." Thesis, Bangor University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.340444.

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13

Söderberg, Axel. "Song recognition in nestling Ficedula Flycatchers." Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-302274.

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14

Michaud, Trista. "The influence of nestling size, parental behaviour, and sibling interactions on fledging in nestling tree swallows (Tachycineta bicolor )." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ49410.pdf.

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Domingo, Ollé Roger. "The glycogen body in neonate birds of the order Psittaciformes and its role in neonate mortality." Giessen : VVB Laufersweiler, 2006. http://geb.uni-giessen.de/geb/volltexte/2007/4441/index.html.

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Glassey, Barb C. "Resource competition among nestling red-winged blackbirds (agelaius phoeniceus)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0021/NQ57508.pdf.

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Mainwaring, Mark Charles. "Evolutionary causes and consequences of hatching asynchrony in nestling birds." Thesis, Lancaster University, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518330.

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Lavigne, André J. "Growth of nestling American Kestrels in relation to dietary factors." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63828.

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19

Hill, Ian Franklin. "Post-nestling mortality and dispersal in Blackbirds and Song Thrushes." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.298192.

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20

Heiss, Rebecca. "American crow nestling growth and nutritional state vary with habitat." Diss., Online access via UMI:, 2006.

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21

Nonaka, Yuki. "Life-History Divergence and Relative Fitness of Nestling Ficedula Flycatcher Hybrids." Thesis, Uppsala universitet, Zooekologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-165807.

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The typical intermediate morphology of hybrids may result in their failure to utilize the same niches as their parents. However, the fitness consequences of the potentially intermediate life-history traits of hybrids have been given less scientific attention. In this study I aimed to investigate how life-history divergence in parental species affects the relative fitness of nestling hybrids resulting from crosses between collared (Ficedula albicollis) and pied flycatchers (F. hypoleuca). Previous studies showed that collared flycatcher nestlings beg more intensively and grow faster under good conditions, but are less robust against the seasonal decline in food availability compared to pied flycatcher nestlings. This life-history divergence between the species allows regional coexistence. To investigate whether the life-history divergence in flycatchers influences the relative fitness of nestling hybrids, I cross-fostered hybrid nestlings in aviaries into the nests of conspecific pairs and compared their performance. I found that the hybrids displayed intermediate growth rates between collared and pied flycatchers across the season. There might therefore be environmental conditions when hybrids perform better than purebred offspring with respect to growth and survival.

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Frumkin, Ron. "Egg quality, nestling development and dispersal in the sparrowhawk (Accipiter nisus)." Thesis, University of Oxford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.480582.

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Goodship, Nicola M. "Endocrine control of nestling begging behaviour in the pied flycatcher, Ficedula hypoleuca." Thesis, Cardiff University, 2006. http://orca.cf.ac.uk/56109/.

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Begging signals given by nestling birds may advertise their condition or quality and parents may respond by allocating their resources in relation to begging intensity. In order for such signals to be honest, they must be costly to produce. The aim of this project was to investigate the role of nestling endogenous testosterone (T) as a potential mechanism to control begging signals in pied flycatchers, Ficedula hypoleuca. Androgen levels were analysed from invasive and non-invasive (faecal) samples using T radioimmunoassay. In the laboratory, nestling begging behaviour was measured as: 1) the duration of begging displays and 2) the maximum height of begging stretches. It was found that individual nestlings begging most intensively had the highest circulating levels of T immediately after testing. This relationship was tested experimentally by dosing nestlings with oral doses of T and assessing the effects on nestling begging signals. The results showed that the duration of begging displays by T-dosed nestlings were longer than controls, confirming the causal nature of T in controlling nestling begging signals. A field study investigated the effect of brood reduction on parental provisioning strategies, nestling behaviour and T levels. During brood reduction parents allocated food resources according to rules based more strongly on nestling begging behaviour compared with control days. A partial cross-fostering experiment tested whether nestling T and begging behaviour related to levels of relatedness within the nest. The begging duration of cross-fostered broods was longer than control broods and fostered nestlings increased their faecal androgen levels, although the reliability of this result should be further investigated. A biochemical validation study confirmed that excreted androgen metabolites were measured in the faeces of pied flycatchers. Overall, the results of this project confirmed that T is responsible in part for the control of begging intensity and may be a mechanism that controls begging behaviour in nestling birds.

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Russell, Janet. "Chick diet and nestling condition among Atlantic puffins at three northwest Atlantic colonies." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp03/MQ47473.pdf.

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Canestrari, Daniela. "Individual variation in nestling care in cooperatively breeding carrion crows Corvus corone corone." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613711.

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Johnston, Ross D. "Effects of nestling diet quality on the growth and adult size of passerine birds." Thesis, University of Stirling, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.281224.

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Gjerdrum, Carina. "Nestling growth and parental provisioning of tufted puffins, Fratercula cirrhata, on Triangle Island, British Columbia." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ61559.pdf.

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Tsang, P. (Poying). "Nestling growth and breeding biology of great tit, blue tit, willow tit and crested tit." Master's thesis, University of Oulu, 2018. http://urn.fi/URN:NBN:fi:oulu-201805312306.

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The correlative relationship of growth rate constant, environmental variables and life history traits was studied in the nestlings of the great tit, the willow tit, the crested tit and the blue tit in the Oulu area of northern Finland in 1969, 1977–1981 and 2017. All the species reached their species specific asymptotic weights by the age of 13–14 days. The asymptotic weight of the great tit was relatively lower than the adult weight compared with the other parids studied. The mortality rate of the nestling great tits was higher than of the crested and willow tits in 2017. Large intial brood size pose an negative imapct on the great tit mass growth. It is possiblely related to the high energy maintainence from the parents and unpredictable weather reduces food supply. The high number of hatchlings seems to be related to increasing nestling mortality in the great tit. After the brood reduction, parents can better nourish the rest of the nestlings which leads to a positive association between the number of fledged chicks and the growth rate constant. We did not find any significant relationship between the ambient temperature and growth rate constant in any of the species. It can be associated with the method of collecting the temperature data. However, the amount of rainfall during the nestling period was positively related to the wing growth rate constant in great tits. The late hatched willow tit nestlings grew faster than the early nestlings. There was a trade-off for the timing of breeding in the willow tit. The early nestling might be able to prepare themselves into breeding population while the late nestling might receive better nourishment from their parents. Besides, the brood size at hatching were markedly related to the growth rate constant in the willow tit. This possibly reflects the female quality and habitat quality in the Oulu area. The growth rate constant of different species was related to the body size, clutch size, and species specific breeding strategies.

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Sadondo, Phenias. "The influence of temperature on parental investiment in Common Fiscal and consequences for nestling growth." Master's thesis, University of Cape Town, 2014. http://hdl.handle.net/11427/9192.

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Includes bibliographical references.
Global climate models project a 1.5-4oC increase in the Earth’s temperature by 2100. Africa, especially southern Africa, is expected to experience not only an increase in average temperatures but also an increase in the frequency and duration of extreme temperature events. Increasing temperatures will result in increased vulnerability to heat and drought stress to biodiversity. A recent paper by Cunningham et al. (2013) showed that temperature has a negative effect on daily mass gain in the nestlings of Common Fiscal (Lanius collaris) breeding in the southern Kalahari. This effect may be driven by parents modifying their provisioning rates at high temperature, but the mechanisms underpinning the relationship are not known. I investigate the influence of temperature on parental investment in Common Fiscal and the consequences of high temperatures for nestling growth using data from videos that were filmed in the Kalahari, Northern Cape, South Africa. Daily mass gain by nestlings increased with increasing provisioning rate and decreased in relation to the proportion of time chicks spent panting. Prey provisioning decreased with temperature in larger broods, however, there was no evidence to suggest that parents trade off provisioning and nest attendance. This might mean that prey availability is reduced at high temperatures, or that parents prioritise their own thermoregulation over provisioning.

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Dearborn, Donald C. "Nestling behavior of a brood parasite : food acquisition and predation risk of brown-headed cowbirds /." free to MU campus, to others for purchase, 1997. http://wwwlib.umi.com/cr/mo/fullcit?p9837723.

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31

Gard, Nicholas W. (Nicholas William) 1962. "Influence of brood-size manipulation on nestling growth, fledging success and parental behaviour in American Kestrels." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61866.

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Olinger, Ryan. "How does temperature affect Fork-tailed Drongo, Dicrurus adsimilis, foraging effort, nestling provisioning and growth rates?" Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/25053.

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Global average temperatures are predicted to increase by as much as 5ᵒC by 2100. Therefore, it is imperative to identify how species are affected by temperature increase to ensure that proper conservation and management of wildlife can be implemented. Species which already live in warmer climates, such as deserts, may provide the first clues to the impacts of increasing temperatures. Birds represent an ideal indicator because research has shown that rising temperatures affect their behaviour, including foraging and provisioning of young, thereby reducing reproductive success. However, it remains unclear whether this results from physiological constraints on behaviour, from declining food availability and or access to prey items at high temperatures. In this study, I aimed to identify how temperature affects the foraging and provisioning behaviour of wild Fork-tailed Drongos, Dicrurus adsimilis, when supplemental food is provided. Additionally, I aimed to identify how nestling growth rates change with temperature. The results of two supplemental feeding experiments indicated that as temperatures increased, adults significantly reduced their willingness to forage, reduced provisioning to offspring and exhibited increased rates of heat dissipation behaviour. Furthermore, when provisioning nestlings, adult drongos consumed a larger proportion of supplementary food at higher air temperatures, and provisioned less. This suggests that they suffer greater provisioning costs at such times. Surprisingly, despite finding several negative effects of temperatures on adults' willingness to forage and provisioning, there was only a weak and non-significant effect of temperature on nestling growth rates. This suggests that adults may be able to compensate for reduced foraging at high temperatures. My study shows that the increased thermoregulatory costs of activity at high temperatures can constrain foraging and provisioning, even when food remains abundant. However, whether this impacts the fitness of current offspring or parents future reproductive success remains unclear.

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Dodson, Jenna C. "PROTHONOTARY WARBLER NESTLING DIET AND GROWTH IN RESPONSE TO VARIATION IN AQUATIC AND TERRESTRIAL FOOD AVAILABILITY." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3969.

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Food supply has been suggested as the main determinant of reproductive success in birds. Riparian species can take advantage of seasonal pulses of both terrestrial and aquatic prey, though aquatic resources are often overlooked in studies of diet and reproductive ecology. This study investigates the flux of both aquatic (mayfly) and terrestrial (caterpillar) prey resources and nestling diet of the Prothonotary Warbler throughout the breeding season in two eastern Virginia sites. One site had significantly higher aquatic prey (mayfly) availability. Nestling diet was generally reflective of prey availability, and nestlings grew faster at the site with high aquatic prey availability. At the site with low aquatic prey availability, nestling growth rates and condition were positively correlated with the amount of aquatic prey in the diet. Our results provide evidence that aquatic subsidies are an important resource for nestlings, and are crucial to understanding the breeding ecology of riparian species.

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Hudson, Nathan Cole. "Nest success, nesting habitat, & nestling feeding rates of red-headed woodpeckers in east-central Illinois /." View online, 2009. http://repository.eiu.edu/theses/docs/32211131592149.pdf.

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McRoberts, Karen Michele. "Investigation of large-scale mortality in nestling straw-necked ibis (Threskiornis spinicollis) with emphasis on giardiasis." Thesis, McRoberts, Karen Michele (2000) Investigation of large-scale mortality in nestling straw-necked ibis (Threskiornis spinicollis) with emphasis on giardiasis. PhD thesis, Murdoch University, 2000. https://researchrepository.murdoch.edu.au/id/eprint/52079/.

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The straw-necked ibis (Threskiornis spinicollis) is a large wading bird of the family Plataleidae, subfamily Threskiomithidae, endemic to Australia and Papua New Guinea. It breeds in large, noisy colonies, often numbering in thousands to tens-of-thousands of breeding pairs. This thesis was undertaken to investigate sickness and mortality occurring in ibis nestlings at two colonies in Western Australia (Capel, approximately 300 km south of Perth, and Cataby, 160 km north of Perth). A multi-disciplinary approach was taken. A detailed post-mortem and clinical investigation was conducted (gross pathology, bacteriology, toxicology for selected pesticides and heavy metals, parasitology, haematology, biochemistry, and limited virology using scanning electron microscopy). As a result of these investigations, Giardia, a flagellate protozoan known to cause disease in many vertebrate species, was the only consistent pathogen recognised. Toxicological studies were negative, and haematological and biochemical results inconclusive. As such, cohorts of nestlings were monitored over time for prevalence of Giardia infection, weight gain, and survival. Histological studies and statistical analyses were used to determine whether or not Giardia was responsible for sickness and death in the ibis nestlings. The progress of infected birds removed from the wild and held in captivity was also monitored. As a first step in determining if infection might be a threat to other avian species, Giardia prevalence in other wild bird species was investigated. In an effort to better understand the nature of isolates obtained, they were characterised using scanning electron microscopy and multi-locus enzyme electrophoresis, then compared with avian isolates described by other researchers. A detailed clinical and post-mortem investigation was conducted during the 1993 breeding season. Giardia trophozoites were detected histologically in the duodenums of seven of 28 birds examined, but there was no histological evidence of pathogenicity. Twenty-six of the 28 birds had trophozoites in scrapings of duodenal contents. Blood smears from nine of 25 birds examined exhibited numerous immature heterophils, a condition that may have been indicative of serious disease; however, no cause could be found and the condition was not associated with Giardia infection or ill health. Further, Giardia infection was not associated with weight loss or death. During the 1993 breeding season, the mortality rate of birds wing-tagged at approximately two to three weeks of age and monitored to fledging (seven to nine weeks of age) was found to be 48% at Capel and 83% at Cataby. During three breeding seasons (1990 to 1993), the overall prevalence of Giardia infection of young ibis at both sites was 74%. Prevalence was significantly higher at Cataby than at Capel (χ21= 5.76, P< 0.05), and was significantly higher at Capel in 1992 than in 1991 (χ21= 6.67, P < 0.05), although these results may have been influenced by the different ages at which birds were sampled. The proportion of infected birds at Capel increased from 1991 to 1993 (χ21= 4.72, P < 0.05). This work indicated that Giardia infection is probably endemic in these populations and that prevalence varies between sites and seasons. Sick birds removed from the wild thrived in captivity and were successfully released. Treatment with dimetradazole appeared to clear the birds of giardial infection, with no cysts being evident in faeces later than one week after treatment. The survey conducted for the presence of Giardia included species of birds nesting with infected ibis, and other species collected near Perth. One-hundred and forty-eight individual birds, representing 39 species, were examined. Nine birds. representing two orders and four species, were positive for Giardia'. one rufous night heron (Nycticorax calendonicus) (n = 1); four great egrets (Egretta alba) (n = 9); three sacred ibis (Threskiornis aethiopica) (n = 7); and one Pacific black duck (Anas superciliosa) (n = 12). All positive samples came from living birds at the Capel site. with the exception of one from a sacred ibis collected in suburban Perth. These results suggest that Giardia infection is not widespread among bird taxa in Western Australia; but that ciconiiforms are principal carriers of Giardia in wild bird populations, as appears to be the case in North American situations. The survey results also suggest that infection with Giardia among wild birds in south-western Australia may be confined to particular wetlands, and that ardeids such as the great egret (Egretta alba) nesting near infected straw-necked ibis may also have high infection rates. Attempts were made to adapt a commercially-available enzyme-linked immunosorbent assay (ELISA), used for the detection of Giardia antigen in human faeces, for antigen detection in ibis faeces. The ELISA achieved a 100% specificity. but sensitivity was poor and was thought most likely to be a reflection of a low concentration of antigen in the ibis faecal samples. Scanning electron microscopy (SEM) and multi-locus enzyme electrophoresis (MLEE) performed on the ibis isolates showed them to have identical enzyme profiles and morphology, suggesting that one strain was infecting birds at both colonies. Comparison with G. ardeae, isolated in the U.S.A. from the great blue heron, Ardea herodias, (Erlandsen et al., 1990), revealed distinct enzyme profiles and morphology, although the ibis strain shared some bands and most morphological characteristics with G. ardeae. Comparison with isolates of Giardia obtained from humans (G. duodenalis) revealed a very different enzyme profile and morphology. This suggested that the ibis-derived isolates may have no zoonotic potential; although humans can be infected with genetically different strains, isolates similar to G. ardeae have not been recovered from humans. It was concluded that one strain of Giardia was infecting birds at both sites. that it was probably closely related to G. ardeae, and was not likely to possess zoonotic potential. Giardia was highly prevalent in ibis nestlings, but, as a sole factor, did not appear to be causing the deaths observed. However, because it was the only potential pathogen consistently identified, the role of Giardia infection in conjunction with some other factor or factors should be further investigated.

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Tastayre, Corinne. "Why do cavity nesters have a longer nestling period than open nesters? A comparative study of alternative hypotheses." Thesis, University of Ottawa (Canada), 1996. http://hdl.handle.net/10393/9557.

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To reduce predation on their progeny, passerines evolved two basic nesting patterns: (1) concealing nests or constructing them in inaccessible places, or (2) breeding inside cavities where offspring are relatively protected. These two nesting patterns seem to lead to different length of nesting cycle. Nice (1957) was the first to report that cavity-nesting species have a longer nestling period than open-nesting species. Why does such a difference in nestling period exist? The goals of my study were: (1) to verify the earlier observation that cavity nesters have a longer nestling period than open nesters; (2) to test the assumption that predation is more intense on nest contents of open nesters than cavity nesters, thereby presenting an important selective force favoring different lengths of the nestling periods of the two groups; and (3) to test two hypotheses on the occurrence of different length of nestling periods between the two groups of passerines. (Abstract shortened by UMI.)

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Parsons, Rebecca Lynn. "Effects of brood size on and the ontogeny of the stress response in nestling Tree Swallows (Tachycineta bicolor)." [Ames, Iowa : Iowa State University], 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1468121.

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38

Robinson, Douglas A. "The relationship of nestling qualities to survival and breeding strategies of cooperatively breeding American crows in Ithaca, NY." Diss., Online access via UMI:, 2009.

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39

Zimunya, Tapiwa. "The influence of vulture restaurants on breeding success and nestling body condition of Gyps vulture populations across southern Africa." Master's thesis, University of Cape Town, 2018. http://hdl.handle.net/11427/29719.

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Vulture populations in many parts of the world continue to decline owing to numerous threats, such as lack of adequate food sources, poisoning and collisions with power-lines. Worldwide, supplementary feeding sites (hereafter, vulture restaurants) have been used as a conservation tool aimed at supporting vulture populations. However, in many parts of the world there is little scientific evidence about their effectiveness in aiding vulture populations. Here, I assessed the relationship between chick condition (African White-backed Vultures) and breeding success (Cape Vultures/African White-backed Vultures) in relation to a variety of variables which described levels of access to vulture restaurants. My data suggest the potential of vulture restaurants to increase breeding success in vulture populations. Breeding success generally increased for nests closer to vulture restaurants. There was a significant positive correlation between African White-backed Vulture breeding success and proximity to vulture restaurants (p< 0.05), but little evidence to support such a relationship for Cape Vultures (p> 0.05). Nestling body condition of African White-backed Vultures was also not influenced by proximity to vulture restaurants (p> 0.05). Findings of this study provide motivation on the use of vulture restaurants as a conservation strategy across southern Africa. The current study informs future conservation efforts on the use of vulture restaurants across the region, particularly in countries where a network of vulture restaurants is still being established.

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Markham, Ann Catherine. "The Influence of Salinity on Diet Composition, Provisioning Patterns, and Nestling Growth in Bald Eagles in the Lower Chesapeake Bay." W&M ScholarWorks, 2004. https://scholarworks.wm.edu/etd/1539626453.

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Lopes, Cláudia Maria Gomes. "Barn swallows' diet in the montado." Master's thesis, Universidade de Évora, 2018. http://hdl.handle.net/10174/23686.

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As aves são um grupo importante no equilíbrio dos ecossistemas devido aos serviços que proporcionam. A andorinha-das-chaminés é uma ave insectívora geralmente associada a actividades humanas, com a sua dieta baseada em estádios voadores de insectos, principalmente Diptera, Hymenoptera e Coleoptera. Neste estudo, avaliámos a dieta de uma população de andorinha-das-chaminés nidificante num ecossistema seminatural – o montado –, aplicando o método do colar em crias. Avaliámos se existiam diferenças na composição da dieta entre períodos de amostragem ao longo de Abril e Maio de 2012, bem como entre dípteros de diferentes funções ecológicas. Os resultados confirmaram a preferência pelas três ordens insectívoras descritas, com Diptera totalizando 65%. Não foram registadas diferenças na biomassa média consumida entre períodos, idade das crias e funções ecológicas, mostrando um equilíbrio no consumo energético, embora haja consumo de diferentes tipos de presas; Barn swallow’s diet in the montado Abstract: Birds are an important group in the equilibrium of the ecosystems due to the services they provide. The barn swallow is an insectivorous bird generally associated to human activities, with their diet being based on winged life stages of insects, mainly Diptera, Hymenoptera and Coleoptera. We evaluated the diet of a barn swallow population breeding in a semi-natural ecosystem – the montado –, applying the ligature method on nestlings. We evaluated if there were differences in the diet among sampling periods along the months of April and May (2012), as well as among different ecological functions of Diptera. Results confirmed the preference for the three main insect orders, with Diptera reaching 65% of the total. There were no differences in mean biomass consumed throughout periods, nestling’s age and ecological functions, showing equilibrium of the energetic intake despite the different types of prey consumed.

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Bruendl, Aisha Colleen. "Parental investment across an altitudinal gradient in blue tits (Cyanistes caeruleus)." Thesis, University of Exeter, 2017. http://hdl.handle.net/10871/33248.

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Environmental gradients can help shed light on the evolution of life history strategies such as parental investment. Parental investment is crucial for the fitness of many species. In this thesis, I examine reproductive investment dynamics in the Eurasian blue tit (Cyanistes caeruleus) in the French Pyrenees and assess potential differences in reproductive measures across an altitudinal gradient that creates variation in environmental “harshness”. Further, I investigate fine-scale aspects of bi-parental care, such as investment tactics in current reproduction, and sex differences in contributions to offspring care. To do so, I used a mixture of observational and experimental data, collected over a total of six breeding seasons from over 500 blue tits nests. I showed that breeding conditions are “harsher” due to colder temperatures with increasing elevation, leading to changes in reproductive timing and output. I found that increasing altitude leads to decreased hatching success. Nevertheless, clutch size and brood mortality is comparable across the gradient. A shift to a lower, but qualitatively comparable reproductive output may be part of a slower “pace of life” strategies pursued at high relative to low altitudes. From experimental data, I also found that parental investment is positively linked across different phases within one reproductive attempt. Finally, in line with theory, a temporary brood manipulation revealed that parents balance the benefits and costs of reproduction by partially compensating for changes in brood size. Parents also responded in similar ways to brood size. Overall, the findings presented in this thesis highlight the importance of mechanisms to fine-tune reproduction to maximise reproductive fitness. I suggest that initial reproductive decisions such as timing and amount of offspring produced heavily shape the success of a reproductive attempt. These results have implications for current versus future reproductive trade-offs in life history theory, in particular for short-lived species.

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Clement, Michelle Elaine. "Cutaneous Water Loss and Covalently Bound Lipids of the Stratum Corneum in Adult and Nestling House Sparrows (Passer domesticus) from Desert and Mesic Habitats." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1306941870.

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水谷, 瑞希, and Mizuki Mizutani. "針葉樹人工林におけるカラ類２種の繁殖生態と餌資源利用様式." 名古屋大学農学部附属演習林, 2002. http://hdl.handle.net/2237/8601.

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Kimball, Scott Allen. "Mating System Dynamics in Passerine Birds." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1242317441.

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Lepczyk, Christopher Andrew. "Can altricial nestlings compensate for ephemeral reductions in food abundance?" 1996. http://catalog.hathitrust.org/api/volumes/oclc/36871398.html.

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Wang, Chen-ning, and 汪辰寧. "Diet and activity pattern of Tawny fish owl(Ketupa flavipes) nestlings in Wuling." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/08555137319429039627.

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碩士
國立屏東科技大學
野生動物保育研究所
101
Tawny Fish Owl (Ketupa flavipes) is the only riparian owl in Taiwan and is one of the few nocturnal raptors which receive much research attention. Early studies focused on this species were mostly done in low elevation. Qijiawan River in Wuling is a unique stream ecosystem that is the major habitat of Formosan Landlocked Salmon (Oncorhynchus masou formosanus) and one of the highest areas within Tawny Fish Owl’s distribution range in Taiwan. Hence, this study utilized telemetry and infrared video camera to study the breeding ecology of Tawny Fish Owl in Wuling. I found two breeding territories of 5.3 km and 7.75 km length, and judging from the number of other non-breeding territories, two breeding territories might be the capacity of Wuling. The incubation period was 36-41 days which began in mid-February and ended in early April. Nestling period was approximately 56-57 days from early April to late May. All 3 nests recorded were located on cross-sections of trees with DBH > 1 m in primary forests, showing certain level of dependency on primary forests. Fish and amphibians comprised of the majority of the nestlings’ diet (47.8% and 42.8%, respectively). The findings of this study showed that the Tawny Fish Owl in Wuling used different nest sites and had different diet composition compared with populations in lower elevations, presumably due to difference in available resources. In addition, climate, individual, breeding pressure, season and the distance from nest to foraging site could all influence the breeding behaviors of Tawny Fish Owl. Compared with previous nest observation data, nestling’s diet could not represent adult’s diet. Division of work was obvious between sexes, where females stayed in nests in early nestling period and later join in the hunt, and males provided prey throughout the entire breeding season.

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Wu, Ching-wen, and 吳靜雯. "Food Resources Analysis of Black-faced Spoonbill (Platalea minor) Nestlings by Using Stable-carbon Isotope." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/32867109738816208304.

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碩士
國立臺南大學
生態科學與技術學系環境生態碩士班
101
Black-faced spoonbill (Platalea minor) nests on breeding islands in the western coast of the Korean peninsula and was known to use both types of food sources, marine food from intertidal area and freshwater food from rice paddy. In order to estimate the relative proportion of marine and freshwater food in the diets of nestlings on different breed islands, I have investigated the diet resources of Black-faced spoonbill nestlings by using stable-carbon isotope analyses of nestlings’ feather from Suhaam, Namdong and Gujido breeding islands. Mean δ13C values for Gujido, Namdong, Suhaam nestling’s feathers were -19.54‰, -17.4‰, -15‰, respectively. The relative contribution of each diet source was estimated using Isotopes Mixing model. The proportion of freshwater food in the diets of all nestlings is 52%, of Gujido, Namdong, Suhaam nestlings were 64%, 48% and 30%, respectively.

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葉佳芬. "The effect of individual heterozygosity on body size, immunocompetence in Green-backed tit (Parus monticolus) nestlings in Central Taiwan." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/ctn8yq.

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碩士
國立臺灣師範大學
生命科學研究所
97
Heterozygosity advantage refers heterozygous individual having higher fitness than homozygous ones, i.e. natural selection may favor individuals with maximum genetic heterozygosity. Association between neutral genetic heterozygosity of an individual and its fitness components, such as survival and fecundity, are well established, but the relationship between heterozygosity and morphological traits of nestlings has been little studied. Here, I measured 99 green-backed tit (Parus monticolus) nestlings’ body mass and tarsus length on the 3rd and 11th day since hatching, and immune response. I then regressed these factors on individual heterozygosity index: individual’s internal relatedness (IR), as estimated from 18 microsatellite loci. The result obtained by multiple linear regression after controlling for nest and brood size shows significant negative correlation between immunocompetence and IR (p=0.010) , and positive local effect of IR at locus Titgata89 on body mass on the 3rd day of hatching (p=0.0001). This study clearly reveals heterozygosity fitness correlations in terms of both general effect and local effect. Furthermore, I found that correlations between heterozygosity and body mass during early developmental period disappear in later period; this may provide explanation for the lack of correlation between adult heterozygosity and morphological traits.

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Xiong, Ye. "Early dietary effects of arachidonic acid on gene expression linked to immune response and metabolism in rural and urban Great Tit (Parus Major) nestlings." Thesis, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-339547.

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This study was conducted to test the silver spoon hypothesis that earlylife nutritional conditions impact development, performance and fitness of the birdsgreat tit (Parus major) nestlings. We investigated whether fatty acid affects immunityand metabolism during the altricial period by examining the expressions of geneTLR4 (immunity related) and COX 2 (metabolism related) against a dietarymanipulation on great tit nestlings in urban vs. rural environments. The resultssuggested that arachidonic acid had no significant effect on TLR4 expression, but atendency to induce immune response, regardless of urban or rural conditions. Thestrength of immune response was however negatively correlated with laying date. Theurban great tit nestlings had a higher COX 2 gene expression than rural ones, andarachidonic acid suppressed COX 2.Thus no strong support to the hypothesis was found for the studied great titpopulations. It showed, however, i) there is a tendency of increasing immune responsewith extra fatty acid in the diet, and ii) arachidonic acid suppress metabolism. Fattyacid involved in a multiple physiological processes and this complex need to beelaborated in future studies.

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Dissertations / Theses on the topic 'Nestlings'

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