Dissertations / Theses on the topic 'Migratory pattern'

Master of Science<br>Department of Biology<br>Alice Boyle<br>Species extinctions over the past two centuries have mainly been caused by habitat destruction. Landscape change typically reduces habitat area, and can fragment contiguous habitat into remnant patches that are more subject to anthropogenic disturbance. Furthermore, changes in the landscape matrix and land-use intensification within remaining natural areas can reduce habitat quality and exacerbate the consequences of habitat loss and fragmentation. Accordingly, wildlife conservation requires an understanding of how landscape structure influences habitat selection. However, most studies of habitat selection are conducted at fine spatial scales and fail to account for landscape context. Temperate grasslands are a critically endangered biome, and remaining prairies are threatened by woody encroachment and disruptions to historic fire-grazing regimes. Here, I investigated the effects of habitat area, fragmentation, woody cover, and rangeland management on habitat selection by two species of declining grassland-obligate sparrows: Henslow’s Sparrows (Ammodramus henslowii) and Grasshopper Sparrows (A. savannarum). I conducted >10,000 bird surveys at sites located throughout eastern Kansas, home to North America’s largest remaining tracts of tallgrass prairie, during the breeding seasons of 2015 and 2016. I assessed the relative importance of different landscape attributes in determining occurrence and within-season site-fidelity of Henslow’s Sparrows using dynamic occupancy models. The species was rare, inhabited <1% of sites, and appeared and disappeared from sites within and between seasons. Henslow’s Sparrows only settled in unburned prairie early in spring, but later in the season, inhabited burned areas and responded to landscape structure at larger scales (50-ha area early in spring vs. 200-ha during mid-season). Sparrows usually settled in unfragmented prairie, strongly favored Conservation Reserve Program (CRP) fields embedded within rangeland, avoided trees, and disappeared from hayfields after mowing. Having identified fragmentation as an important determinant of Henslow’s Sparrow occurrence, I used N-mixture models to test whether abundance of the more common Grasshopper Sparrow was driven by total habitat area or core habitat area (i.e. grasslands >60 m from woodlands, croplands, or urbanized areas). Among 50-ha landscapes containing the same total grassland area, sparrows favored landscapes with more core habitat, and like Henslow’s Sparrows, avoided trees; in landscapes containing ~50–70% grassland, abundance decreased more than threefold if half the grassland area was near an edge, and the landscape contained trees. Effective conservation requires ensuring that habitat is suitable at spatial scales larger than that of the territory or home range. Protecting prairie remnants from agricultural conversion and woody encroachment, promoting CRP enrollment, and maintaining portions of undisturbed prairie in working rangelands each year are critical to protecting threatened grassland species. Both Henslow’s Sparrows and Grasshopper Sparrows were influenced by habitat fragmentation, underscoring the importance of landscape features in driving habitat selection by migratory birds. As habitat loss threatens animal populations worldwide, conservation efforts focused on protecting and restoring core habitat could help mitigate declines of sensitive species.

Title from PDF of title page (University of Missouri--Columbia, viewed on March 2, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Dr. Trudy Lewis, Dissertation Supervisor. Vita. Includes bibliographical references.

Migration theories, which guided prior research, have been predominantly based on static dichotomous categorizations. In particular most research has been guided by assumptions conceiving migration primarily as: 1) a one-off move from a departure country “A” to a destination country “B”; 2) directed to Europe (revealing a strong Eurocentric bias); 3) entailing a permanent settlement; 4) and with little or no spontaneous return from Europe to origin countries. According to this logic, previous research concentrated almost exclusively on specific phases of the migration process (settlement and integration in destination countries; temporary returns and circulation between sending and receiving countries; permanent return in origin countries) or on their effect on sending and receiving countries. Furthermore, available data on migration are few, weakly comparable and fail to capture the longitudinal character of migration. These limitations particularly apply to migration from sub-Saharan Africa, where the diversification and growing complexity of migratory flows, rather than an increase in volume (as conveyed by public opinion and the media) has been the most significant change in the last decades. In addition to conceptual problems, this lack of data prevents gaining an improved understanding into the complex and rapidly changing dynamics of African migrations. The aim of the PhD research is to fill these conceptual and empirical gaps by analyzing migration trajectories as 1) complex mobility systems, conceiving migration as a continuous process that develops over migrants’ lives through different phases and steps; 2) from the origin country, through intermediate-transit and destination ones 3) studying the extent of mobility within the EU 4) and including (short and long-term) circulation and permanent returns to origin country. Following these principles, the theoretical and empirical objective of the study is to identify and to analyze the main migration patterns between Africa and Europe, through a longitudinal analysis of their complex composition, geographical extent and changing nature over time. The research draws on the MAFE dataset, which provides a unique opportunity to empirically pursue this research objective. The MAFE Senegal project yielded a new individual biographic data set in 2008, through comparables surveys in both sending (Senegal) and receiving countries (France, Italy, Spain) among both documented and undocumented migrants. MAFE data are: 1) multi-topic (various aspects of the respondents' lives are covered by the questionnaires, including work experience, family formation, residential mobility, legal status, etc.); 2) multi-level (meso and macro comparable data in four surveyed countries are associated to individual-micro data on migrants); 3) longitudinal (through retrospective data) 4) transnational (collected and giving account for both sending and receiving countries). The unique nature of this dataset allows to undertake innovative research on complex structure of individuals’ migration. By investigating the individual migrants’ trajectories, the research focuses in particular on “transits” and “temporary returns”. The analysis showed the increasing crucial role of interconnectivity played by these forms of mobility between West African and European migration systems. Finally, by analyzing the intersections of the different mobility structures (linear, step-wise and circular) and geographical areas (sub-Saharan Africa, North Africa and Europe) in which Senegalese migration develops, the research finally elaborates a typology of the main patterns of mobility between Africa and Europe and outlines the profiles of migrants who undertake different mobility patterns.

One of the most fascinating aspects of birds is their capability of migrate from one area to another throughout the year. Unravelling the patterns and processes involved in the evolution of migration is paramount to understand the current biogeography, ecology and evolution of migratory birds. On this basis, the main aim of the present thesis was to extend the knowledge of the mechanisms involved in the evolution of bird migration. To achieve that two main sections are presented in this thesis. In the first one, the aims were to disentangle the patterns of evolution of migratory behaviour and the identifying the main factors that could play an important role in it, using Sylvia warblers as case of study. In the second section, we explored the climatic niche and the potential distribution of breeding and wintering ranges in the last glacial maximum (LGM) of trans-Saharan long migratory species, in order to unravel the changes in migratory behaviour. We explored the evolution of migration in Sylvia warblers as both a discrete and continuous character using ancestral state reconstruction methods. We recovered the basal node as migratory in most analyses, suggesting seven independent losses of migratory behaviour in Sylvia warblers. Both analyses performed with migration as discrete or continuous character recovered different probabilities of sedentariness or migratoriness in some conflicting nodes depending of the ASR elements used. This forced as to consider controversial hypotheses of evolution of migration in some clades that could evolved from migratory to sedentary in a very short period of time or going through a partial migratory status instead. We used phylogenetic comparative methods to assess whether the evolutionary patterns of migratory distances are correlated with several biometric, climatic and productivity variables in a phylogenetic context, using Sylvia warblers as a case study. Our results recover net primary productivity (NPP) in the breeding range and during the breeding season as the variable with stronger positive correlation with migratory distances. Several climatic variables show a correlation with the evolution of migration and among morphological variables, migratory lineages tend to have longer wings than sedentary ones. It is not possible to disentangle if NPP was a main driver in the evolution of bird migratory behaviour or a consequence of it, yet migration and NPP seem to be tightly related today and along their evolutionary history. Migratory birds occupy different geographic areas during breeding and wintering periods and are exposed to different factors. One of those factors is the climatic component of the niche. We tested if migratory birds display similar climatic conditions in both breeding and wintering areas, using 355 bird migratory species from Eurasian to Africa flyways. Our results show that there is not climatic niche overlap between both ranges. This suggests that the climatic niche of most Euro-African migratory species is larger than expected. Given these results, both breeding and wintering climatic data need to be considered when performing species distribution models, to incorporate the total width of the climatic niche. During the Plio-Pleistocene, glacial cycles have shaped Northern Hemisphere birds' distributions that could result in changes in their migratory behaviour. In this context, it has been suggested that long-distance North American migratory species could have lost their migratory condition during cold periods regaining it later in warmer periods. We tested this hypothesis in Eurasian-African extant migratory bird species. We modelled present and LGM distribution of 80 trans-Saharan bird migratory species and we revised the available fossil record. Our results show a southwards reduction of the breeding distributions during the LGM compared to the present and similar wintering areas in the present and Pleistocene, with the Saharan belt gap always present through time. These results and the Pleistocene fossils from Africa not support the hypothesis of a loss of migratory condition in these species.<br>Uno de los aspectos más fascinantes dentro de la ornitología es el estudio de la migración. Saber cuáles son los patrones y procesos implicados en la evolución de la migración, permite descubrir tanto componentes ecológicos, biogeográficos como evolutivos dentro las aves. Por ello, en esta tesis se pretende aumentar el conocimiento acerca de los mecanismos implicados en la evolución de la migración en algunas aves. Por un lado, se investigó cómo evolucionó la migración y qué factores pueden actuar como motores de su evolución en un contexto filogenético usando el género Sylvia como caso de estudio. Encontramos que los procesos de cambio en el comportamiento migratorio ocurrían siempre de migratorio a sedentario, siendo el antecesor del género también migratorio. Esto supone que probablemente el coste de pasar de migratorio a sedentario es menor que al revés. Además, evaluando si factores como el clima, la morfología o la productividad eran importantes en la evolución de la migración en el género Sylvia, encontramos que la productividad juega un papel muy importante. Esto supone que probablemente las especies comenzaron a migrar aprovechando los picos de productividad que surgen en latitudes medias durante la época de cría. Por otro lado, se investigó la evolución de la migración en un contexto biogeográfico y macrecológico utilizando especies migratorias Euro-Africanas. Primero se evaluó si las especies migratorias están sometidas a las mismas condiciones climáticas tanto en las zonas de cría como en invernada. Si fuera así, las especies migratorias podrían moverse guiándose o en busca de condiciones similares a lo largo de todo el año. Sin embargo, encontramos que no es así y por lo tanto las especies migratorias presentan un nicho climático mayor de lo esperado que es necesario tener en cuenta a la hora de hacer modelos de distribución. Considerando esto, realizamos modelos de distribución de especies transaharianas tanto en el presente como durante el último glacial máximo. En este caso queríamos descubrir si las especies seguían migrando cuando parte del Paleártico estaba cubierto de nieve, o si se hicieron sedentarias como se ha sugerido para especies migratorias norteamericanas. Nuestros resultados, junto con el registro fósil consultado, no apoyan que las especies dejaran de migrar, sino que probablemente redujeran sus distancias migratorias.

The migration of graduates is one of the main characteristics of the current phase of Italian emigration. This thesis investigates why Italian graduates are migrating both within and outside Italy. The main research questions this thesis gravitates around are: why do Italian graduates migrate? What is the difference, if any, in terms of motivations, between graduates who decide to migrate internally within Italy as compared to the ones who decide to migrate to the UK? Why do some graduates stay in their home town despite regional and national differentials in terms of employment and lifestyle opportunities? Namely, this thesis examines and compares the motivations that drove three samples of Italian graduates to migrate. Firstly, those who migrated to the UK; secondly, those who from the southern Italy moved internally to the Italian cities of Rome (centre) and Milan (north); and thirdly, those who decided to stay in the Italian cities of Palermo (south), Rome (centre), and Milan (north). The analysis proposed is qualitative and exploratory in nature and is based on 87 in-depth interviews conducted with Italian graduates in 2008-2009. The study provides an integrated view of different migratory patterns. In particular, the comparison between internal and international flows indicates that Italian graduates are generally oriented towards the UK and particularly towards London because of the many professional, educational and cultural opportunities that London as a global city has to offer. Meanwhile, internal migration within Italy (south to north) is generally experienced as constrained by deep regional differences in terms of employment opportunities between southern and northern Italy. Finally, staying in one's home town emerged as a decision based, among other factors, on the lack of interest in experiencing mobility vs. the importance a person attributes to social, emotional and cultural ties to his or her own family, friends, partners and the local area.

In recent years, human decision-making has led to significant landscape impacts in the western United States. Specifically, migratory wildlife populations have increasingly been impacted by rural urban development and energy resource development. This research presents the application of agent-based modeling to explore how such impacts influence the characteristics of migratory animal movement, focusing on mule deer (Odocoileus hemionus) in Western Wyoming. This study utilizes complex adaptive systems and agent-based modeling frameworks to increase understanding of migratory patterns in a changing landscape and explores thresholds of interference to migration patterns due to increased habitat degradation and fragmentation. The agent-based model utilizes GPS-collar data to examine how individual processes lead to population-level patterns of movement and adaptation. The assessment incorporates elements from both human and natural systems to explore potential future scenarios for human development in the natural landscape and incorporates adaptive behaviors, as well as animal-movement ecology, in changing landscapes.

Understanding migratory connectivity is essential for assessing the drivers behind population dynamics and for implementing effective management in migratory species. Genetic markers provide a means to describe migratory connectivity, as well as incorporate population genetic analyses, however genetic markers can be uninformative for species with weak genetic structure. In this study, we evaluate range-wide population genetic structure and migratory connectivity in the prothonotary warbler, Protonotaria citrea, a wetland-dependent neotropical migratory songbird, using high-resolution genetic markers. We reveal regional genetic structure between sampling sites in the Mississippi River Valley and the Atlantic Seaboard with overall weak genetic differentiation among populations (FST = 0.0051). By ranking loci by FST and using subsets of the most differentiated genetic markers (200 – 3000), we identify a maximum assignment accuracy (89.7% to site, 94.3% to region) using 600 single nucleotide polymorphisms. We assign samples from unknown origin nonbreeding sites to a breeding region, illustrating weak migratory connectivity between prothonotary warbler breeding and nonbreeding grounds. Our results highlight the importance of using high-resolution markers in studies of migratory connectivity with species exhibiting weak genetic structure. Using similar techniques, studies may begin to describe population genetic structure that was previously undocumented, allowing us to infer the migratory patterns of an increasing number of species.

The spatial and temporal variability of migratory phenology of <i>Ciconia ciconia, Cuculus canorus, Apus apus, Hirundo rustica</i> and <i>Luscinia megarhynchos</i> were studied by means of 44000 records for 1400 spanish sites during the period 1944-2004. In all species, first individuals arrive to the southern areas of Iberia, to low altitude sites, with dry and warm summers, and near to the Straits of Gibraltar. A. apus and <i>H. rustica</i> showed quite similar spatial patters due to the strong influence of fixed factors, which impose optimum migratory pathways. The onset of singing of <i>C. canorus</i> and <i>L. megarhynchos</i> showed a different and weak geographical pattern, which suggests that other local environmental factors could be influencing singing behaviour of males. In spite to be a soaring species, <i>C. ciconia</i> follows similar spatial patters for spring arrivals. However, its autumn departure and length of stay did not show any spatial gradient. Excepting <i>L. megarhynchos</i>, all species have advanced their arrival dates during the last three decades. Nevertheless, current dates are similar to those recorded sixty years ago. The strongest advancement was detected in <i>C. ciconia</i>, probably as a result of the growing number of wintering individuals in Iberia. In overall, species arrived earlier those years with plentiful rainfalls in western Africa and warmer spring temperatures in Iberia. Therefore, climate change is probably the underlying mechanism for temporal changes in migratory phenology also in Mediterranean populations. Departure dates only showed a significant advancement in <i>H. rustica</i>. Departures were weakly related to climatic variables. Temperatures during breeding period advanced departures in all species, while only <i>H. rustica</i> was affected by temperatures at departure time.<br>S'estudià la variabilitat espacial i temporal en la fenologia de la migració de diverses aus trans-Saharianes. Es van fer servir unes 44000 dates d'arribada i emigració de cigonya ("Ciconia ciconia"), cucut ("Cuculus canorus"), falciot ("Apus apus"), oreneta ("Hirundo rustica") i rossinyol ("Luscinia megarhynchos") enregistrades a unes 1400 localitats espanyoles entre 1944 i 2004 pels voluntaris de la xarxa fenològica de l'"Instituto Nacional de Meteorologí"a.<br/>Totes les espècies colonitzen la Península Ibèrica seguint un eix sudoest-nordest durant la primavera. Els primers individus arriben al sud, a localitats a baixa altitud, amb estius secs i calorosos i properes a l'Estret de Gibraltar. En el cas de l'oreneta i el falciot els patrons van ser especialment similars degut a la dependència de factors ambientals invariables, com ara el relleu, que marquen les rutes migratòries òptimes a través de la península en ambdues espècies. L'inici del cant va mostrar patrons espacials diferents en el cucut i el rossinyol, probablement com a resultat de la biologia tan diferent d'ambdues espècies. L'escassa capacitat predictiva dels seus models podria indicar que el cant també depèn d'altres factors que incideixen sobre les decisions dels mascles de cantar o no fer-ho i que són alienes a la migració. L'arribada de la cigonya segueix els patrons generals citats anteriorment tot i ser una espècie planadora. Pel contrari, les diferències entre localitats en les dates d'emigració i la durada de l'estada no tenen cap estructura espacial en aquesta espècie. Les cigonyes es reuneixen en grans estols durant la migració post-nupcial que tenen un comportament independent de les condicions ambientals de les localitats on crien. L'estada depèn més de la data quan els individus decideixen marxar, que de la data quan arriben.<br/>La cigonya, cucut, falciot i oreneta han avançat la seva data d'arribada durant els darrers trenta anys, tot i que les dates enregistrades a l'actualitat són semblants a les que s'enregistraven ara fa seixanta anys. L'excepció és la cigonya, que sí ha avançat l'arribada en torn un mes. Aquest canvi tan brusc probablement està relacionat amb el nombre cada cop més gran d'individus que roman a la península durant l'hivern. Aquesta tendència a no migrar possiblement és el resultat combinat dels costos d' anar a les àrees clàssiques d'hivernada del Sahel, on les sequeres persistents provocarien una elevada mortalitat entre els individus que hi van, en comparació amb els beneficis de romandre tot l'any a la península, on la proliferació de deixalleries i certes espècies invasores proporcionen una font contínua d'aliment que abans no existia. L'arribada es va veure afectada tant pel clima de les àrees d'hivernada com el de cria en la resta d'espècies. Les aus arriben abans els anys humits a l'Àfrica occidental i les primaveres càlides a la península. Els canvis climàtics de les darreres dècades són, doncs, els responsables més probables dels canvis temporals en les dates d'arribada. Les dates d'emigració de la cigonya, falciot i oreneta van mostrar fluctuacions temporals similars, avançant la seva sortida fins a mitjans dels 60, ajornant-la fins a mitjans dels 80 i tornant-la a avançar d'ençà les hores. Temperatures elevades durant l'època de reproducció es van associar amb un avançament de l'emigració a les tres espècies, mentre que només l'oreneta es va veure afectada per les temperatures durant el període d'emigració, anant-se més tard aquells anys més calorosos durant aquestes dates. Podem concloure que les xarxes de voluntaris constitueixen una bona eina per avaluar la variabilitat espacial escala i temporal de la migració de les aus i que s'haurien de seguir potenciant, especialment ara, donada la sensibilitat de la fenologia al canvi climàtic.

A região central de Portugal representa o limite sul da distribuição dos dois ecótipos de Salmo trutta L, o residente (i.e., truta-de-rio) e o anádromo (i.e., truta-marisca). Para além dos constrangimentos a uma escala mais global que as espécies de peixes experienciam, como o aquecimento global, os rios dessa região estão severamente fragmentados pela presença de grandes barragens e pequeno-médios açudes, construídos maioritariamente para a produção de eletricidade e recolha de água para uso doméstico, industrial e para a agricultura. Esforços direcionados ao aumento do conhecimento sobre a truta em resposta às pressões antropogênicas e pela mitigação da fragmentação do habitat existente, têm sido constantemente desenvolvidos nos últimos 8-10 anos no Rio Mondego. Considerado um dos mais importantes rios em Portugal para peixes migradores, uma passagem para peixes de fendas verticais (i.e., 125 metros de comprimento, 23 bacias) foi construída em 2011 no Açude-Ponte de Coimbra e monitorização contínua vem sendo realizada desde 2013 com recurso a censos visuais. Os dados de contagem sobre a truta revelaram que entre 2013 e 2017 mais de 300 trutas utilizaram com sucesso a passagem durante a sua migração para montante. Nos anos estudados, os meses com maior contagem de trutas foram maio (21,1%), junho (52,7%) e julho (14,3%). O padrão circadiano dos movimentos para montante revelou que as trutas migraram pela passagem maioritariamente ao amanhecer e no final do dia. O tamanho das trutas utilizando a passagem com sucesso foi dependente do mês, pois as maiores trutas (CT>300 mm) tendem a usar a passagem mais cedo (em maio), seguida daquelas de menores dimensões (CT<300 mm), que tendem a utilizar a passagem mais tarde na época de migração (julho). Modelos exploratórios revelaram que fatores ambientais como o fotoperíodo e o período do dia, estão significativamente influenciando o uso da passagem para peixes pelas trutas durante todos os anos de estudo; Abstract: Study of Migration Behavior of Trout (Salmo trutta L.) in the Southern Limit of its Distribution The central region of Portugal represents the southern limit of the distribution of both ecotypes of Salmo trutta L, the resident (i.e., brown trout) and anadromous (i.e., sea trout). Besides the constraints, such as global warming, that the species experiences, rivers in this region are severely fragmented by the presence of large dams and small-to-medium weirs, built mainly for hydroelectricity production and water abstraction for domestic, industrial and agriculture uses. Efforts towards an increase in the knowledge of trout responses to anthropogenic pressures and for the mitigation of existent habitat fragmentation have been consistently developed for the last 8-10 years in Mondego River. Considered one of the most important rivers in Portugal for migratory fish, a vertical-slot fishway (i.e., 125 meters long, 23 pools) was built in 2011 at the Coimbra dam and monitoring is continuously being conducted since 2013 using visual census. Count data on trout revealed that between 2013 and 2017 more than 300 trouts have successfully used this fish pass during their upstream migration. In the studied years, the months with the highest trout count were May (21.1%), June (52.7%) and July (14.3%). Circadian pattern of upstream movement revealed that trouts migrate through the fish pass mostly in the morning and at the end of the day. Size of trout successfully using the fish pass was month dependent, as larger trouts (CT>300mm) tend to use the fish pass earlier (in May), followed by those with smaller dimensions (CT<300 mm), that tend to use the fish pass later on the migration season (July). Explanatory models revealed that different environmental factors, such as photoperiod and day period, are significantly influencing fish pass use by trout in all the studied years.

Thesis (Ph. D.)--Joint Program in Oceanography/Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Biology; and the Woods Hole Oceanographic Institution), 2007.<br>Includes bibliographical references (p. 188-204).<br>Geochemical signatures in the otoliths of diadromous fishes may allow for retrospective analyses of natal origins. In an assessment of river-specific signatures in American shad (Alosa sapidissima), an anadromous clupeid native to the Atlantic coast of North America, stable isotope and elemental ratios in otoliths of juvenile American shad produced accurate natal tags from 12 rivers. Significant inter-annual variability in geochemical signatures from several rivers was detected, due largely to differences in 8180 values among years. The database was further expanded to include 20 rivers from Florida to Quebec, encompassing all major spawning populations. This task was accomplished by collecting juvenile otoliths along with water samples from rivers where juveniles were not sampled. Regressions between otolith and water chemistry for those rivers where both were collected showed significant relationships for Sr:Ca, Ba:Ca, 86180, and 87Sr:86Sr ratios but not for Mg:Ca or Mn:Ca. Despite reducing the combined signature to only four chemical ratios, cross-validated classification accuracies of known-origin juveniles averaged 93%. Ground-truthed signatures were used to classify migrants of unknown origins. Adults returning to spawn in the York River were classified according to their otolith composition.<br>(cont.) Only 6% of spawners originated from rivers other than the York, supporting the hypothesis that most American shad spawn in their natal river. Of remaining spawners, 79% originated from the Mattaponi River and 21% from the Pamunkey River. The results suggested that while most American shad home to their natal river there is less fidelity to individual tributaries, allowing subsidies to subpopulations with persistent recruitment failure. Otolith signatures were also used in mixed-stock analyses of immature migrants along the coast of Maine in the spring and Minas Basin in the summer. Mixed-stock compositions showed remarkably low diversity and were dominated by fish from the Shubenacadie and Hudson rivers, with an increasing proportion of Potomac River fish over time. In contrast to results from adult tagging studies, southern stocks were virtually absent. These data suggest ontogenetic shifts in migratory behavior. The thesis concludes with a report that water contributed 83% of Sr and 98% of Ba in the otoliths of a marine fish.<br>by Benjamin Walther.<br>Ph.D.

Survivorship (the likelihood of survival from one year to the next) and breeding dispersal (movement between breeding seasons) exhibit considerable variability at both the inter- and intraspecific levels. Using eight years of data (2008-2015), from my study site in southwest Oklahoma, I characterized survivorship and breeding dispersal of the Scissor-tailed Flycatcher (Tyrannus forficatus) in a mixed-grass prairie ecoregion. My results suggest that estimated survivorship of Scissor-tailed Flycatchers is low, especially to the congeneric Eastern Kingbird (T. tyrannus), and was likely underestimated due to the tendency of Scissor-tailed Flycatchers to disperse long distances.

Bio-archaeology is the study of biological remains found at sites of archaeological interest. It is an interdisciplinary science employing different scientific fields including physical anthropology, geography, archaeology and genetics. Genetic analysis includes ancient DNA (aDNA) studies, now a specialised field in genetics. This approach was used to analyse human skeletal material of eight individuals from various Iron Age archaeological sites in southern Africa. Included in this sample is a naturally mummified individual from Tuli, in Botswana. The context of the specimens found in the Limpopo Province (Thulamela), as well as their cultural links with the Zimbabwe Culture Complex (which includes Mapungubwe and Khami) suggests that some gene exchange might have occurred. While this is not the first aDNA study on southern African samples, it is the first aDNA study based on southern African Iron Age human individuals and also included a naturally mummified individual. Morphometric and morphological analyses have indicated the age at death, sex and health status of the individuals, and the context in which they were found has helped in assessing their cultural affinity. Bone samples were analysed in a specialized aDNA laboratory at the Centre for Evolutionary Medicine in Switzerland. Following DNA extraction, ancestry-specific mitochondrial DNA was amplified from all samples and was compared to that of modern sub-Saharan Africans whose data were accessed from GenBank. Some individuals show (maternal) genetic similarities to present-day Sotho/Tswana groups. The male individual from Thulamela aligns somewhat more with the groups from the west and the female with the eastern peoples. Two Early Iron Age individuals from Happy Rest presented some similarities to the Khoesan peoples. Genetic-sex determination efforts were inconclusive for all individuals. The purpose of this study was to place the Thulamela individuals within the context of the genetic diversity in South Africa. It was noted that the introduction of genetic material from the early Sotho/Tswana was gradual in the case of Thulamela. Two other individuals from Happy Rest, who were contemporaries of each other, showed very little genetic variation and it can be said that their maternal DNA was of the same (possibly Khoesan) origin. Further resolution in haplotype assignment will be done in future. These temporally and spatially dispersed individuals can only provide a glimpse into the population interactions of the Iron Age that may have partially shaped the immense genetic diversity of present-day southern Africa.<br>Dissertation (MSc)--University of Pretoria, 2014.<br>tm2015<br>Anatomy<br>MSc<br>Unrestricted

Large population declines for sand tiger sharks (Carcharias taurus) in parts of its global range are well documented, resulting in a strong need for biologically informed conservation and management measures. Although sand tigers in the western North Atlantic have been listed as a Species of Concern by the US government since 1997, details of their seasonal migratory movements and especially vertical habitat use patterns along the US East Coast are limited. Understanding these movement patterns is vital to reducing fishery-related mortality of these sharks and informing other management efforts aimed at recovery of their stocks in the US Atlantic. Although survey and fishery-dependent data have revealed a general picture of the seasonal distribution patterns of sand tiger sharks, details of the areas specifically used by these sharks and their movements between such areas remain unclear. Additionally, information on vertical habitat use such as preferred depth and temperature, as well as variability observed among sexes, size classes and geographic locations would provide insight into the fine-scale distribution of sand tigers to aid better management practices. Here, I report on the horizontal and vertical movements of sand tiger sharks along the US East Coast determined through use of pop-up archival transmitter (PAT) tags and supplemental acoustic telemetry. PAT tags were deployed on 14 sand tiger sharks in Delaware Bay in late summer 2008. Sufficient archived depth and temperature data were obtained from 11 sharks (eight male, three female), and sufficient light data allowed construction of long-term horizontal tracks for 10 sharks (seven male, three female) using a Kalman filter state-space model. Duration of tag deployment per animal ranged from 64-154 days ( =121.6). All seven male sharks left Delaware Bay in late summer/early autumn and migrated south along the US East Coast reaching waters off North Carolina, where they remained until transmitter detachment during the winter months. In contrast, all three females moved out of Delaware Bay into deeper, offshore waters east of the bay near the continental slope. During southern migration of males, average depth utilized was positively correlated to shark size. The smallest males spent on average over 90% of their time in waters <40 >m, whereas intermediate and large sized males spent only 54 and 38% of their time at depths <40 >m, respectively. Female sharks spent an average of 46% of their time in waters range, spending at least 95% of their time in waters 17-23oC, with little difference between size classes or sexes. Horizontal movements of male migrating sand tigers also revealed several areas of concentrated activity along their southern migratory routes. Migratory patterns of sand tiger sharks along the US East Coast appear most similar to patterns displayed by this species along the coast of South America. Further delineation of western North Atlantic continental shelf and slope core areas of sand tiger shark activity, especially for females, will inform efforts to reduce interactions with commercial fisheries and measures to avoid habitat degradation - management aspects that will aid in reducing mortality and enhance rebuilding of sand tiger stocks along the US East Coast.

The blue shark (Prionace glauca) is among the most abundant and widely distributed of all oceanic elasmobranchs. Millions of blue sharks are caught annually worldwide in pelagic long line fisheries, and it accounts for the largest component of auctioned fin weight in the international shark fin trade. There is growing concern about the depletion of its populations worldwide and impacts of such large scale removal of an apex predator on oceanic ecosystem stability. The fragmentary nature of life history information available for blue sharks, including on its detailed movement and migratory behavior, continues to limit management efforts that require such data for stock assessment and sustainable catch modeling. To assist in obtaining a better understanding of blue shark movement behavior in the western north Atlantic, I used satellite telemetry to investigate the detailed habitat utilization and movements of sharks during the summer months when the sharks form aggregations on the continental shelf off the Northeast United States, and during their fall , pelagic migrations. Thirty-one (26 male, 5 female) blue sharks were tagged with pop-up archival satellite transmitters. The transmitters reported data from a total of 1,656 combined days, yielding 74,163 depth recordings and 74,125 temperature recordings. Tracked sharks exhibited two distinct movement patterns: During the summer months, the sharks remained within a restricted geographical area south of Nantucket Island and spent nearly 80% of their time in the uppermost part of the water column in <20 m depth (mean depth of 8 m). During fall months (October and November) the sharks made fairly directed offshore and southerly movements, with several sharks associating with waters east of Bermuda. During their pelagic migrations, the sharks demonstrated markedly different water column utilization behavior. They occupied much greater depths (127 m mean depth) and exhibited a clear diel depth pattern, occupying deeper water during the day and shallower water at night, not observed on the shelf. The longest duration track was that of an immature female for nine months. The greatest distance traveled was by a mature male that moved from Martha's Vineyard, MA to waters near Puerto Rico (a linear distance > 4,000 km). There was some indication that the different demographic groups (mature males, immature males, and immature females) may display different movement behavior, especially during their pelagic migrations. This study provides the first detailed information on habitat utilization and movement patterns of blue sharks in the Western North Atlantic, and points to the need for further investigation of movement behavior by different demographic segments of the population.

Stable isotope analysis is an emerging tool to examine trophic pathways and migratory patterns of marine organisms. Squid are widely distributed in coastal and deep water regions of the Gulf of Mexico. Stable isotope ratios of carbon and nitrogen found within cephalopod tissues can provide information on both trophic level and habitat of their food sources. More recently, ontogenetic changes in stable isotope ratios within squid eye lenses have been documented. Concentric layers of crystallin proteins are added to the lens as the squid ages; the center of the lens contains the oldest layer and the youngest layers are on the outermost surface. The crystallin proteins are rich in carbon and nitrogen, providing suitable sources for isotopic analysis of both δ15N and δ13C. Doryteuthis plei is a common inshore squid in coastal waters of the western Atlantic region. This study identifies the geographic movements of D. plei in the eastern Gulf of Mexico using changes in isotope ratios in eye-lens layers. Isotopic analyses suggest that these squid begin their lives in the deep chlorophyll maximum of the outer shelf and move inshore as they age.

Tuna are the major marine fishery in Sri Lanka, and yellowfin tuna (YFT) (Thunnus albacares) and skipjack tuna (SJT) (Katsuwonus pelamis) represent 94% of all tuna caught. The tuna catch in Sri Lanka has increased rapidly over recent years and this is true generally for the Indian Ocean. Tuna are a major animal protein source for 20 million people in Sri Lanka, while marine fisheries provide the main income source for most Sri Lankan coastal communities. While the importance of the fishery will require effective stock management practices to be employed, to date no genetic studies have been undertaken to assess wild stock structure in Sri Lankan waters as a basis for developing effective stock management practices for tuna in the future. This thesis undertook such a genetic analysis of Sri Lankan T. albacares and K. pelamis stocks. Samples of both YFT and SJT were collected over four years (2001 - 2004) from seven fishing grounds around Sri Lanka, and also from the Laccadive and Maldive Islands in the western Indian Ocean. Partial mitochondrial DNA (mtDNA) ATPase 6 and 8 genes and nuclear DNA (nDNA) microsatellite variation were examined for relatively large samples of each species to document genetic diversity within and among sampled sites and hence to infer stock structure and dispersal behaviour. Data for YFT showed significant genetic differentiation for mtDNA only among specific sites and hence provided some evidence for spatial genetic structure. Spatial Analysis of Molecular Variance (SAMOVA) analysis suggests that three geographically meaningful YFT groups are present. Specifically, one group comprising a single site on the Sri Lankan west coast, a second group comprising a single site on the east coast and a third group of remaining sites around Sri Lanka and the Maldive Islands. Patterns of variation at nDNA loci in contrast, indicate extensive contemporary gene flow among all sites and reflect very large population sizes. For SJT, both mtDNA and nDNA data showed high levels of genetic differentiation among all sampling sites and hence evidence for extensive spatial genetic heterogeneity. MtDNA data also indicated temporal variation within sites, among years. As for YFT, three distinct SJT groups were identified with SAMOVA; The Maldive Islands in the western Indian Ocean comprising one site, a second group comprising a single site on the east coast and a third group of remaining sites around Sri Lanka and the Laccadive Islands. The mtDNA data analyses indicated two divergent (M^ = 1.85% ) SJT clades were present among the samples at all sample sites. SJT nDNA results support the inference that multiple 'sub populations' co-exist at all sample sites, albeit in different frequencies. It appears that variation in the relative frequencies of each clade per site accounts for much of the observed genetic differentiation among sites while effective populations remain extremely large. Based on combined data sets for management purposes therefore, there is no strong evidence in these data to indicate that more than a single YFT stock is present in Sri Lankan waters. For SJT however, evidence exists for two divergent clades that are admixed but not apparently interbreeding around Sri Lanka. The identity of spawning grounds of these two clades is currently unknown but is likely to be geographically distant from Sri Lanka. Spawning grounds of the two distinct SJT clades should be identified and conserved.

Tuna are the major marine fishery in Sri Lanka, and yellowfin tuna (YFT) (Thunnus albacares) and skipjack tuna (SJT) (Katsuwonus pelamis) represent 94% of all tuna caught. The tuna catch in Sri Lanka has increased rapidly over recent years and this is true generally for the Indian Ocean. Tuna are a major animal protein source for 20 million people in Sri Lanka, while marine fisheries provide the main income source for most Sri Lankan coastal communities. While the importance of the fishery will require effective stock management practices to be employed, to date no genetic studies have been undertaken to assess wild stock structure in Sri Lankan waters as a basis for developing effective stock management practices for tuna in the future. This thesis undertook such a genetic analysis of Sri Lankan T. albacares and K. pelamis stocks. Samples of both YFT and SJT were collected over four years (2001 - 2004) from seven fishing grounds around Sri Lanka, and also from the Laccadive and Maldive Islands in the western Indian Ocean. Partial mitochondrial DNA (mtDNA) ATPase 6 and 8 genes and nuclear DNA (nDNA) microsatellite variation were examined for relatively large samples of each species to document genetic diversity within and among sampled sites and hence to infer stock structure and dispersal behaviour. Data for YFT showed significant genetic differentiation for mtDNA only among specific sites and hence provided some evidence for spatial genetic structure. Spatial Analysis of Molecular Variance (SAMOVA) analysis suggests that three geographically meaningful YFT groups are present. Specifically, one group comprising a single site on the Sri Lankan west coast, a second group comprising a single site on the east coast and a third group of remaining sites around Sri Lanka and the Maldive Islands. Patterns of variation at nDNA loci in contrast, indicate extensive contemporary gene flow among all sites and reflect very large population sizes. For SJT, both mtDNA and nDNA data showed high levels of genetic differentiation among all sampling sites and hence evidence for extensive spatial genetic heterogeneity. MtDNA data also indicated temporal variation within sites, among years. As for YFT, three distinct SJT groups were identified with SAMOVA; The Maldive Islands in the western Indian Ocean comprising one site, a second group comprising a single site on the east coast and a third group of remaining sites around Sri Lanka and the Laccadive Islands. The mtDNA data analyses indicated two divergent (M^ = 1.85% ) SJT clades were present among the samples at all sample sites. SJT nDNA results support the inference that multiple 'sub populations' co-exist at all sample sites, albeit in different frequencies. It appears that variation in the relative frequencies of each clade per site accounts for much of the observed genetic differentiation among sites while effective populations remain extremely large. Based on combined data sets for management purposes therefore, there is no strong evidence in these data to indicate that more than a single YFT stock is present in Sri Lankan waters. For SJT however, evidence exists for two divergent clades that are admixed but not apparently interbreeding around Sri Lanka. The identity of spawning grounds of these two clades is currently unknown but is likely to be geographically distant from Sri Lanka. Spawning grounds of the two distinct SJT clades should be identified and conserved.

The present research project aimed to investigate the struggles undocumented Sudanese migrant face to circumvent legal and geographical borders and to gain some form of citizenship. I focused on the kind of journeys, referred to as sombok, their precondition, narration and social practices implemented along the irregular routes from Sudan to the United Kingdom. In doing so, particular interest was paid to the production, circulation and resilience of migratory knowledge roaming in transnational networks and resulting in consequent mobility patterns, tenaciously and ceaselessly reproduced. Indeed, despite the increasing difficulties, due to massive investment in border patrolling and externalisation of controls, it is apparent that this does not deter people from migrating and neither does it prevent arrivals and movements in Europe.

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>As tartarugas marinhas são espécies ameaçadas, altamente migratórias que apresentam um ciclo de vida longo e uma ampla distribuição geográfica. Assim, melhorar a nossa compreensão sobre a ecologia espacial das tartarugas marinhas é essencial para a elucidação de aspectos da sua história de vida e para o desenvolvimento de medidas eficazes de conservação. Esta tese compreende um conjunto de artigos ou capítulos que visam contribuir ao conhecimento da ecologia espacial da tartaruga-de-couro, Dermochelys coriacea. Este estudo utilizou novas tecnologias como à telemetria por satélite (que proporciona um método útil para monitorar os movimentos de espécies migratórias) e um conjunto de ferramentas de geoprocessamento como abordagem metodológica que visou: examinar os movimentos e migrações da tartaruga-de-couro, identificar áreas de uso intenso e padrões espaço-temporais no uso do habitat, e integrar dados biológicos e oceanográficos para descrever as estratégias comportamentais desta espécie. Cinco tartarugas-de-couro (um subaduto, dois machos adultos e duas fêmeas adultas) foram equipadas com transmissores por satélite no Atlântico Sul Ocidental entre 2005 e 2008. Além de fornecer dados de localização geográfica os tansmissores permitiram registrar informações de mergulho tais como profundidade e duração máxima e media dos mergulhos, perfis completos de mergulhos individuais e dados de temperatura do mar. Movimentos e migrações de tartarugas-de-couro marcadas no Atlântico Sul foram documentados pela primeira vez. Alem disso, foi posível identificar áreas de uso intenso (ou alimentação) previamente desconhecidas para a espécie, assim como uma residência sazonal nestas áreas localizadas em águas tropicais e temperadas fora da costa sul-americana (19-45S). A sazonalidade dos movimentos esteve intimamente associada a processos físicos sazonais de pequena e mesoescala. Dependendo do ambiente marinho explorado, durante os períodos de residência, as tartarugas apresentaram diferentes estratégias alimentares identificadas através da análise dos padrões de mergulho.<br>Sea turtles are long-lived, highly migratory endangered species with a wide distribution. Thus improving our knowledge of the spatial ecology of sea turtles is essential for elucidating aspects of their life history and for the development of effective conservation measures. This thesis comprises a collection of articles or chapters that aim to contribute to the knowledge of the spatial ecology of the leatherback turtle, Dermochelys coriacea. This study used new technologies such as satellite telemetry (which provides a useful approach for tracking the movements of migratory species) and a set of geoprocessing tools as a methodological approach that aimed to: examine the movements and migrations of leatherback turtles, identify high use areas and spatio-temporal patterns of habitat use, and integrate biological and environmental data to describe foraging strategies of this species. Five leatherback turtles (a subadut, two adult males and two adult females) were fitted with satellite transmitters in the Southwest Atlantic between 2005 and 2008. Besides providing geographical location data the transmitters also recorded dive information such as mean and maximum dive depth and duration, individual dive profiles and water temperature data. For the first time the movements and migrations of leatherback turtles tagged in the South Atlantic were documented. Previously unidentified high use areas (or foraging areas) were recognized for this species, also a seasonal residence along those areas located in tropical and temperate areas off the coast of South America (19-45 S). The seasonal movements were closely associated with small and mesoscale physical seasonal processes. Depending on the marine environment exploited during periods of residence, the turtles showed different foraging strategies identified through the analysis of the diving patterns.

This is the first study to assess how the coastal migratory stock of striped bass (Morone saxatilis) uses non-natal New England estuaries during their foraging migration. Using hydroacoustic telemetry from June through October in Plum Island Estuary, Massachusetts, I examined how long coastal migratory striped bass stayed throughout the seasons, if they were equally distributed, if individual striped bass were distributed differently, and if distribution changed with season, tide, or light. Striped bass, ages 2-5 (300-480 mm), were tagged with VEMCO transmitters in the spring and summer of 2005 (N=14) and 2006 (N=46). They stayed for an average of 66 days in 2005 (SE=7.6) and 72 days in 2006 (SE=6.2). Of the fish tagged in 2005 and 2006, 60% remained for longer than 30 days. This might reflect two striped bass migration strategies: 1) transient migration, in which striped bass visit many estuaries, and 2) estuary-specific, in which they reside in a single location for the summer. The amount of time the striped bass spent in six reaches delineated within the estuary was quantified. Striped bass were not evenly distributed across these reaches. Instead, they spent the most time in the mid Plum Island Sound and lower Rowley River reaches in both years. Three different uses of PIE were observed. Some striped bass stayed briefly (5-20 d; N=24), some stayed primarily in the Rowley River (N=14), and others stayed primarily in Plum Island Sound (N=22). Striped bass use of the mid Plum Island Sound and lower Rowley River reaches remained consistently high in spring and summer, but decreased in fall, while use of the lower Plum Island Sound did not vary much. Use of other reaches varied seasonally. Tide and light were less associated with distribution, but in the summer the Rowley River use-group increased utilization of tidal creeks during the day, though not at high tide. These three use-groups identified in Plum Island Estuary may be foraging contingents that may learn how to forage in specific parts of the estuary demonstrated by over half the striped bass remaining for much of the summer and congregating in distinct areas.

acase@tulane.edu<br>Tyrannus is a highly diverse genus with respect to migration strategies within the largest adaptive radiation of birds in the world (Tyrannidae). Within the genus, there are Nearctic- Neotropical migrant, Neotropical austral migrant, intratropical migrant, and resident species and subspecies. The overall goal of this dissertation was to use a variety of methods to explain the diversity of migration patterns found in the New World (focusing on the Tyrannus genus) to gain a better understanding of the ecology and evolution of migration in birds. In my first chapter I developed a phylogeny to account for phylogenetic relatedness in analyses demonstrating that natural selection has acted on two morphologies relevant to the strategy-specific niches of migratory versus resident Tyrannus (wing pointedness), which may be part of a suite of co-adaptations that are adaptive for migratory populations. Then I showed that New World migratory passerines are tracking with different aspects of seasonality in the Northern versus the Southern Hemisphere, better equipping further research exploring differential impacts of climate change on different types of migrants. In my final chapter I developed a novel gas-chromatography mass-spectrometry (GC/MS) protocol to discover evidence that austral migrant Fork-tailed flycatchers had higher concentrations of oleic and linoleic acid in their diets compared to residents, demonstrating that a diet switch from insects to fruit is important to fuel spring migration, via the accumulation of polyunsaturated fatty acids (PUFAs). This study has improved our understanding of the ecology and evolution of migration in birds by extending hypotheses developed for Nearctic migrants into a genus with both Nearctic and austral migrants. Taken together, my findings demonstrate important new information for proximate versus ultimate mechanisms driving the evolution of migration in birds, as well as elucidating important ecological patterns of Nearctic-Neotropical versus Neotropical austral migration that may be important for developing species distribution models and conservation plans under climate change scenarios where both future temperature and rainfall regimes are expected to change.<br>1<br>Maggie MacPherson

碩士<br>國立屏東科技大學<br>野生動物保育研究所<br>100<br>In this study, I used stable hydrogen isotope (δDf) to survey migratory restlessness (Zugunruhe) of black-faced buntings (Emveriza spidocephala) and explore their migration pattern. Total of 33 black-faced buntings were bought or captured in this research, the breeding sites of black-faced buntings obtained by examining stable hydrogen isotope (δDf) of their feathers. This research was executed from February to December, 2011. Results revealed that the distance from breeding sites was related to migratory restlessness and the date of migratory restlessness started, but not related to the date of migratory restlessness finished. I speculated that, the distance from breeding sites farther, the migratory restlessness would achieve migration started earlier. Conversely, if the distance from breeding sites nearer, the migratory restlessness lower and migration started later. There is no relation between the date of migratory restlessness of black-faced buntings and the distance from breeding sites, I presumed that birds would rest and supply power at stopover site when they are migrating, this probably effect the date of migratory restlessness finished. This research also found out the migratory restlessness of black-faced buntings was related to their weights, I assumed the foraging strategy of black-faced buntings is supplying energy and migrating in the meantime. Time of the highest migratory restlessness of black-faced buntings was 22:00 to 00:00, it might be the migration peak of black-faced buntings. In the monthly variation of migratory restlessness of black-faced bunting in all year, there is no apparent stop from February to November, only the variation of gradually increase or decrease, I concluded that besides the endogenous control, migratory restlessness of birds was also effected by temperature, physiological condition and other factors.

碩士<br>國立屏東科技大學<br>野生動物保育研究所<br>99<br>This study combined the work of banding with stable hydrogen isotope analysis and DNA sexual detection. The purposes were to examine the altitudinal distribution of Gray-cheeked Fulvetta’s (Alcippe morrisonia) breeding area, migration direction in different seasons, differential migration between sexes and the relationships between the bird’s body measurements and altitude and season in Peitawushan. To obtain the data of the species’ body measurements and the rectrix and blood samples for analysis from Septemper 2009 to February 2010. Results showed that he Fulvetta molted after breeding in the breeding area. Chance is good that birds from >1400 m a.s.l. did not migrate downward to my study site; no fixed direction of altitudinal migration was found between seasons, a possible reason of pursuing movement, escape movement and juvenile dispersal happened during study period. Differential migration existed by sex; the male may be as close as possible to their breeding territory during migration to obtain the advantage in the next breeding season in time. Because the standard of judgment about altitude was too narrow, the study could not verify the Allen’s Rule or Bergmann’s Rule in this species; some measurements related to flight ability were different between seasons, but the reason may be resulted from feather abrasion or the measurement error. For this reason, the effect on the flight ability of Gray-cheeked Fulvetta needs further study.

University of Technology, Sydney. Faculty of Science.<br>NO FULL TEXT AVAILABLE. Access is restricted indefinitely. The hardcopy may be available for consultation at the UTS Library.<br>NO FULL TEXT AVAILABLE. Access is restricted indefinitely. ----- This study recorded and compared the behaviour and physiology of the partially migratory Tasmanian subspecies, Zosterops lateralis lateralis, and the sedentary mainland subspecies, Zosterops lateralis familiaris, of the Australian silvereye over an extended period in captivity. Tasmanian birds were held in captivity for a total of 17.5 months, while the mainland birds were kept for 13 or 16 months, dependent on date of capture. During this time orientation behaviour, locomotor activity, fat deposition, body weight, food consumption and moult of each subspecies were recorded. The Tasmanian birds displayed significant seasonally appropriate orientation during each of the three migratory periods and also during the breeding and moult period. In contrast, the mainland birds did not display significant orientation at any time. Graphing of the locomotor activity revealed several trends in the daily and annual activity patterns of each subspecies. During the first year in captivity the Tasmanian birds exhibited elevated activity levels during the migratory periods, which is most likely due to migratory restlessness and their activity patterns were similar to those of diurnal migrants. The Tasmanian birds were significantly fatter and heavier than the mainland birds and during the first year in captivity; the Tasmanian birds displayed increased fat deposition during the migratory periods and the overwintering period. During the second year in captivity, after moult, both subspecies failed to develop the levels of activity recorded during the previous year and also weighed significantly less. This was especially apparent during the second autumn migration period. During this time the Tasmanian birds also failed to gain the fat levels of the previous year. Captivity appeared to affect both subspecies and influenced the development of migratory activity and fat deposition in the Tasmanian birds. Both subspecies showed similar levels and patterns of consumption of nectar, apple and a protein-mix and nectar consumption had a significant inverse relationship with temperature. The subspecies differed in their consumption of mealworms, with the Tasmanian birds consuming mealworms, in higher numbers and with greater frequency than the mainland birds. Both subspecies moulted at the same time as wild birds. The Tasmanian birds commenced and completed moult earlier than the mainland birds and exhibited less variation between individuals. Overall the differences between the subspecies were consistent with their differing lifestyles and the adaptation of the behaviour and physiology of Tasmanian silvereyes to their migratory habit.

碩士<br>國立臺灣大學<br>海洋研究所<br>102<br>Flying &;#64257;shes (Exocoetidae) distribute worldwide in tropical and sub-tropical waters. In the pelagic food web, flying fish serve as a low trophic-level consumer feeding mainly on zooplankton. The eggs of Hirundichthys oxycephalus are harvested off northeastern Taiwan between April and July and adult fish are the major targeted species off the southeastern coast of Taiwan between March and June. In this study, we analyzed the otolith stable oxygen and carbon isotopic composition of the flying fish (Hirundichthys oxycephalus) collected from the coastal waters of Keelung, Hualien, Green Island, and Goto Island, Japan to reconstruct their migratory patterns. We also analyzed the muscle stable carbon and nitrogen isotope composition of the 9 flying fish species and 15 large fish from the waters off eastern Taiwan in order to understand the food web structure. Otolith stable oxygen isotopic composition shows that H. oxycephalus collected from Goto Island all migrated between Japan and Taiwan; H. oxycephalus collected from Keelung, Hualien and Green Island show different migratory life histories, one migrated between Japan and Taiwan, the others were local residence or stay in specific temperature waters. These results suggest diversified migratory patterns of H. oxycephalus in the waters off eastern Taiwan. Stable carbon and nitrogen isotopic composition shows that Cheilopogon cyanopterus has the highest δ15N value and Cheilopogon unicolor has the lowest δ15N value in the 9 flying fish species. There are two trophic levels differences between large predator fish and flying fish in the waters of eastern Taiwan. Muscle δ13C values suggested that flying fish is one of the main prey fed by the Istiophoridae, Xiphias gladius, Coryphaena hippurus and Prionace glauca.

Important habitats crucial to animal reproduction and survival are being transformed at an increasing rate and at the same time, climate change is altering ecological patterns in both time and space. Migratory species are currently experiencing severe declines as they move within a network of interconnected areas that are often undergoing different rates of change. Understanding the factors that influence population dynamics in migratory species therefore requires not only knowledge on breeding ecology and drivers of breeding success, but also on how events during one period of the annual cycle carry over to influence events in subsequent seasons. The overall objective of this thesis was to increase the knowledge about the breeding ecology and migratory patterns of the European bee-eater (Merops apiaster), an Afro-Palearctic long-distance migrant. More specifically, this thesis focused on increasing the knowledge on trophic ecology as well as providing a first insight of bee-eater’s migratory patterns, at population and individual levels. This work also explored, for the first time, the link between migratory performance and productivity in an Iberian population of this species. Finally, it was investigated if productivity is influenced by age and pair-fidelity. The first two chapters were developed based on the need of the application of the described methods in the subsequent chapters. First, I developed discriminant functions to sex adult bee-eaters. This work was the first using biometrics of molecularly sexed birds to generate population specific, as well as, general discriminant functions for sexing adult European bee-eaters. Then, I also developed a photographic guide to estimate the age of nestling bee-eaters and presented a protocol that proposes visiting nests at 12 day intervals, while achieving the highest accuracy in nestling aging with the smallest disturbance and logistic investment. This thesis showed that the diet of bee-eaters during the breeding season varies across colonies in distinct habitats and seasons, and between what is consumed by adults and provided to nestlings. The results revealed distinct migration patterns of European Bee-eaters from three breeding populations (Iberia, Germany and Bulgaria) showing that individuals from Bulgaria migrate on an eastern route to southern Africa while the other two populations take a western route. It also provided evidence for different timings of migration between the three populations. At individual level, departure from the wintering area and travel duration seemed to be the most apparent factors influencing arrival to the breeding areas in Iberia. In this study, it was reported a positive relationship between arrival and laying dates. Additionally, the relationship between laying date and productivity was year specific: in 2017, the number of fledglings decreased throughout the season, contrary to 2016, when laying was earlier in the year and productivity remained constant. Finally, the results showed that older females (but not males) lay eggs earlier and have higher productivity than first breeding females. Moreover, older couples seemed equally likely to maintain their pair bond during two consecutive seasons than first breeding pairs and productivity does not seem to be influenced by mate retention. Inter-annual variation in productivity may affect populations in the long term if the frequency of poor (or good) environmental conditions increases, as these induce fluctuations in demographic rates. Therefore, this study urges for long-term monitoring of bee-eater populations, and other Afro-Palearctic migrants, to predict their population level responses to environmental change and optimize conservation strategies accordingly.<br>Os habitats essenciais para a reprodução e sobrevivência animal têm vindo a ser transformados a um ritmo crescente e ao mesmo tempo, as alterações climáticas têm vindo a alterar espacialmente e temporalmente os padrões ecológicos. Muitas espécies migradoras estão, actualmente, em declínio severo devido ao facto de ocuparem áreas conectadas entre si que muitas vezes são alteradas a diferentes velocidades. Assim, para compreender os factores que influenciam a dinâmica populacional das espécies migradoras é necessário, não só, aprofundar o conhecimento sobre a sua ecologia reprodutora e os factores que determinam o sucesso reprodutor, mas também perceber de que modo os eventos que ocorrem durante um determinado período do ciclo anual se traduzem em carry-over effects e influenciam os eventos nas épocas subsequentes. O principal objectivo desta tese foi aumentar o conhecimento sobre a ecologia reprodutora e padrões migratórios do Abelharuco (Merops apiaster), um migrador Afro-paleártico de longa distância. Mais concretamente, esta tese focou-se em aprofundar o conhecimento sobre a ecologia trófica, assim como investigar pela primeira vez os padrões migratórios do Abelharuco, a nível populacional e individual. Este trabalho também investigou pela primeira vez a relação entre a performance migratória e a produtividade de uma população desta espécie que nidifica na Península Ibéria. Finalmente investigou-se se a produtividade é influenciada pela idade e fidelidade do casal. Os primeiros dois manuscritos foram desenvolvidos devido à necessidade de aplicar esses métodos nos capítulos seguintes. Primeiro, desenvolvi funções discriminantes para determinar o sexo de Abelharucos adultos. Este trabalho foi o primeiro que utilizou biometrias de Abelharucos, nos quais o sexo foi identificado molecularmente, para produzir funções discriminantes aplicáveis ao nível da população mas também para a espécie em geral. Desenvolvi também um guia de fotografias para determinar a idade das crias de Abelharuco e apresento um protocolo que propõe visitar os ninhos em intervalos de 12 dias de modo a atingir a precisão máxima na determinação da idade das crias, minimizando a perturbação e o investimento logístico. Esta tese mostrou que a dieta do Abelharuco durante a época reprodutora varia entre colónias localizadas em habitats distintos, entre épocas e entre o que é consumido pelos adultos e fornecido às crias. Os resultados revelaram distintos padrões migratórios do Abelharuco entre três populações reprodutoras (Ibéria, Alemanha e Bulgária), indicando que os indivíduos da Bulgária migram através de uma rota este para o sul de África, enquanto as outras duas populações migram por uma rota oeste. Também demonstrou que as três populações exibem diferentes timings de migração. Ao nível individual, a partida da área de invernada e a duração da migração parecem ser os principais factores que influenciam a data de chegada à área de reprodução na Ibéria. Neste estudo, foi estabelecida uma relação positiva entre a chegada à área de reprodução e as datas de postura. Adicionalmente, a relação encontrada entre a data de postura e a produtividade variou entre anos: em 2017, o número de crias voadoras diminuiu ao longo da época reprodutora; mas tal não aconteceu em 2016, quando as datas de postura ocorreram mais cedo e a produtividade permaneceu constante ao longo da época. Finalmente, os resultados mostraram que fêmeas mais velhas (mas não machos) colocam os ovos mais cedo e têm maior produtividade do que as fêmeas que se reproduzem pela primeira vez. Adicionalmente, os casais mais velhos parecem ter a mesma probabilidade de se manter juntos durante duas épocas reprodutoras consecutivas comparado com os casais que se reproduzem pela primeira vez. A produtividade não parece ser influenciada pela manutenção do parceiro. A variação inter-anual na produtividade pode afectar as populações a longo termo através da indução de flutuações nas taxas demográficas, se a frequência de más (ou boas) condições ambientais aumentar. Deste modo, este estudo apela à monitorização a longo prazo das populações de Abelharucos, e outros migradores afro-paleárcticos, de forma a prever as respostas das populações às alterações ambientais e optimizar medidas de conservação.<br>Programa Doutoral em Biologia

Most vertebrates suffer permanent damage after minutes of anoxia. Many insects however, have part of their life cycle in anoxia or constant hypoxia, such as during their egg-hatching phase, by living as deep burrowers, or at high altitudes. Insects are able to survive in anoxia from hours to days, or even months by developing various strategies through evolution. For example, the locusts (Locusta migratoria) enter a reversible coma during anoxia that is associated with an arrest of ventilation, and a reinitiation of ventilation when returned to normoxia. This coma is correlated with a surge in the concentration of extracellular potassium ions ([K+]o), and recovery from this reversible coma is dependent on re-establishing the functional [K+]o. Prior exposure to a sublethal heatshock (HS)-preconditioning grants locusts a temporary resilience to anoxia; however, the molecular mechanisms of this protection are still unclear. This project investigated the effects of HS-preconditioning on locusts’ ventilation, the total enzymatic activity of the Na+/K+-ATPase, as well as its distribution within the metathoracic ganglion and tested the hypothesis that HS-preconditioning alters locusts’ ventilation and increases the totally Na+/K+-ATPase activity and its concentration within neuronal membranes. I recorded electromyograms of locusts’ ventilatory motor patterns in the presence and absence of anoxic coma by placing a copper wire electrode on ventilatory muscles 161 or 173 in control and HS-preconditioned animals. In addition, I studied the enzymatic activity of the Na+/K+-ATPase using a pyruvate kinase/lactate dehydrogenase assay and the localization of the Na+/K+-ATPase using immunohistochemistry in control and HS-preconditioned locusts at different stages of coma. I found that the ventilatory cycle period was decreased and the ventilatory muscle burst duration was increased after recovery from anoxic coma in HS-preconditioned locusts. I also found that anoxia did not affect the activity or the localization of the Na+/K+-ATPase. However, HS-preconditioning increased the total activity of the Na+/K+-ATPase and the localization of the Na+/K+-ATPase within the neuronal membranes. From this project, I concluded that HSpreconditioning affected locusts’ ventilatory motor pattern after recover from anoxia and increased the total activity and the neuronal membrane localization of the Na+/K+-ATPase.<br>Thesis (Master, Biology) -- Queen's University, 2011-09-26 13:14:48.472