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The avian thyroid : Regulation and secretionLam, S. K. January 1986 (has links)
No description available.
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Migration strategies : mechanisms and their consequences in a changing worldKomissarova, Alexandra January 2010 (has links)
Mechanisms and their Consequences in a Changing World Alexandra Komissarova Abstract Many migratory species are responding to climate change by altering their migration behaviour, however, we know relatively little about the mechanisms by which such changes are accomplished. One way in which climate change could be influencing migration strategies is through its effect on habitat and territory quality. I tested several hypotheses of different mechanisms by which three aspects of territory quality could affect migration decisions in a partially migrant bird, the robin (Erithacus rubecula). I also used a theoretical individual-based modelling approach to investigate the interaction between migration and dispersal strategies within a population and examined its underlying mechanisms. Migration decisions were not significantly affected by summer territory quality, as measured by breeding success and summer vegetation structure. Winter territory quality was, however, found to be a good predictor of migration behaviour, with aspects of winter vegetation such as ground cover appearing particularly important. However, this effect of winter vegetation structure on migration decisions appeared to be largely due to its correlation with food availability. Migration decisions were strongly affected by winter food availability, with provisioning of food greatly increasing the numbers of resident individuals. The results of the theoretical model showed a that high rates of dispersal within a population reduced the average proportion of migrants, with the effect strongly influenced by dispersal cost and to a lesser extent, kin selection. I hope that this work will ultimately improve our ability to predict species’ responses to climate change by adding to our understanding of the mechanisms behind migration decisions, while also providing a more holistic view of migration by placing it in the context of other life history decisions.
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The use of fatty acid signature analysis to investigate diets of North Sea seabirdsOwen, Ellie January 2009 (has links)
The aim of this thesis was to advance our understanding of the foraging needs of three North Sea seabirds by using fatty acids analysis, a new tool for seabird ecologists. The first two chapters describe methodological advances in the form of a method for sampling adipose tissue via live biopsy, a simple method for extracting lipids from a variety of seabird tissues and appropriate statistical analysis for detecting differences in fatty acid profiles between groups of ecological interest. Different tissue types were investigated as sources of fatty acids for addressing a range of ecological questions. The remaining chapters present results using fatty acid analysis to investigate the diet of the three study species the black-legged kittiwake (<i>Rissa tridactyla</i>), common guillemot (<i>Uria aalge</i>) and northern fulmar (<i>Fulmarus glacialis</i>), focussing on areas of research which have been difficult to explore using conventional techniques. Diet outside the main breeding season is one such area and fatty acid profiles showed that kittiwake and guillemot sexes fed on similar diets before breeding but male and female fulmars used different foraging strategies. This sex effect did not persist into the chick-rearing period with males and females of all three species feeding on similar diets. Distinct seasonal shifts in fatty acid profiles were observed and adult and chick diets were shown to differ in the single prey loading species, the guillemot. The final chapter presents some of the first evidence suggesting a link between individual variation in diet choice and potential fitness consequences in fulmars.
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Experimental Trichinosis in BirdsPoon, Yau-Lun 12 1900 (has links)
This work concerns itself with essentially four experiments: (1) the cecum-injective-infection experiment; (2) the anus-injective-infection experiment; (3) the mouth ingestive-infection with larvae, and (4) the mouth ingestive-infection with the flesh of infected rats.
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Identifying Priority Conservation Areas for Grassland Birds in the Champlain Valley of VermontSutti, Flavio 02 October 2009 (has links)
For several decades, grassland bird populations have been facing consistent declines throughout North America with population declines >1.5% per year in the past 40 years in the eastern United States. If this current rate persists, the populations will be reduced to half their current size in less than 50 years. Multiple causes have been proposed to explain the decline of grassland birds, but loss of available habitat and declining habitat quality are recognized as key elements in the decline of this guild. The Champlain Valley has the potential to be an important area for the conservation of grassland birds due to large acreage of grassland habitat; however, management practices are not always compatible with grassland bird habitat requirements. Therefore, there is a need to focus conservation efforts in areas that will have the greatest probability of maintaining populations of grassland birds. This project was designed to identify priority areas for implementing conservation programs for grassland birds in the Champlain Valley of Vermont. Using ArcGis, I created detailed layers that included landscape level factors (forest, grassland, development and roads) and patch level factors (size, management and conservation) important in grassland bird habitat selection. Integrating the GIS dataset into a multicriteria decision analysis framework, I produced maps in which grassland patches were ranked on the basis of their quality for grassland birds. The Analytic Hierarchy Process was the decision rule used to identify priority conservation areas. The use of a hierarchical structure distributed the relative weights of different factors deemed important by grassland bird experts, allowing a greater number of criteria to be included while keeping the methodology manageable. These procedures resulted in a series of habitat quality maps that federal, state, and non-governmental land managers will be able to use as a baseline to focus conservation efforts on areas that will have the greatest probability of maintaining viable populations of grassland birds. The maps emphasize the protection of grassland patches larger than 5-10 ha that are 2 km away from roads with high traffic, and the selection of blocks of > 50 ha of protected or bird-friendly grassland habitat. The Analytic Hierarchy Process is a flexible method that can be applied to conservation decisions across a variety of ecosystems and species.
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Výroba vycpanin ptáků a savců / Taxidermy of the birds and mammalsOuřadová, Petra January 2015 (has links)
The main subject of this thesis is the taxidermy. The taxidermal mounts will be used as a teaching tools in teaching practice. The thesis is a comprehensive guide for creation of the taxidermal mounts of birds and mammals. There are described both old and modern methods of taxidermy in this thesis. Thesis is enriched with news from contemporary foreign literature. The result of thesis is 8 mounts (6 birds, 2 mammals) which will use as teaching tools during teaching of biology. Key words: taxidermy, preparation, bird, mammal, teaching tool
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Soaring flight in the steppe eagle (Aquila nipalensis)Gillies, James A. January 2010 (has links)
Avian flight cannot fail to impress; from the huge migratory distances covered by albatrosses to the dexterity shown by a feeding hummingbird, the performance of birds in flight is remarkable. Until now research into free flight (i.e. not in a wind tunnel or other artificial environment) has been limited to observations from the ground. Here I use a collection of novel techniques, based on the use of onboard instrumentation carried by the bird, to explore if and how this performance might be underpinned by their flexible flight configuration. In the Introduction (chapter 1) to the thesis I investigate previous work into the stability and control of birds in flight. In chapter 2 I investigate a selection of manoeuvres seen commonly in flight, and describe the ways in which they exploit the flexible configuration of the eagle. Then (chapter 3), using an Inertial Measurement Unit (IMU) containing an integrated camera and Pilot-tube I measure the forces acting on the body of the bird in flight, the airspeed of the bird, and using custom-written software, I extract the configuration of the tail from the video. Using the measured configuration of the tail I estimate the lift generated by the tail according to a series of simple aerodynamic models. These are good predictors of the variation in the normal load factor acting on the bird. This suggests that the tail of the eagle is used primarily in soaring flight to balance the bird along the pitch axis. In chapter 4 I further investigate the configuration of the tail, I find that the spread and angle of attack of the tail covary, but that the twist of the tail is adjusted independently. In chapter 5 I explore one manoeuvre, the wing tuck, in more detail. With reference to a 'mean wing tuck' of the key variables I suggest that it is a response to a drop in wing loading, which suggests that it may be a response to atmospheric turbulence. I then investigate the frequency of wing tucking and our principal finding is that it is increased on days when the wind speed is greater, further suggesting that it is a response to atmospheric turbulence. Finally in the Discussion (chapter 6) I summarise the thesis. I also consider future avenues for research into the control and stability of avian flight and discuss some of the limitations of the methods used in this thesis.
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Studies on mitogen and co-mitogen from natural sources.January 1988 (has links)
by Song Myung-eun. / Thesis (M.Ph.)--Chinese University of Hong Kong, 1988. / Bibliography: leaves 67-70.
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The effect of particle size on the regional deposition of inhaled aerosols in an avian respiratory tractHayter, Richard Browning January 2010 (has links)
Digitized by Kansas Correctional Industries
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The role of rare and exotic animals in the self-fashioning of the early modern court : the Medici court in Florence as a case studyGroom, Angelica January 2012 (has links)
The principal aim of this study is to investigate the role rare and exotic animals played in the cultural self-fashioning and political imaging of the Medici's Ducal and Grand-ducal Court in Florence (1531-1737). The exclusive focus on this topic will contribute to Medicean scholarship in an area of research that has hitherto received only scant and fragmentary attention. This study will provide the first comprehensive and systematic analysis of the numerous ways in which both real and depicted animals were manipulated to serve the interests of the Medici regime. The thesis is formed of five chapters. Chapter one examines the zoological spaces established by the Medici; chapter two focuses on the procurement of animals and their use in diplomatic gift exchange. The remainder of the thesis takes the form of three case studies. These will examine a wide range of Medici-commissioned works of art, from different points in the family's history, in which unusual fauna feature as a central element of the iconography. The works discussed will make clear how individual members of the regime deployed animal imagery to express their political aspirations and courtly magnificence. Case study one traces how early members of the Medici family used images of rare beasts to assert their dynastic and political legitimacy, primarily to a home audience. Case study two examines the role of zoological illustrations in the Medici's wider ambition to establish an international reputation as patrons of the natural sciences and to promote the court as a centre of artistic production. The final case considers a series of zoological paintings commissioned by the last two Medici rulers, to argue that the pictures reflected not only the shifting values elite society attached to unusual fauna, but that they also mirrored the decline of the regime itself.
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