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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

Birds in Residential Metropolitan New Orleans Neighborhoods and Their Relationships to the Batture and Yard Vegetation

Guymon, Ruth A 02 August 2012 (has links)
Metropolitan New Orleans Neighborhoods were surveyed in order to determine how bird populations responded to distance from the batture, percent canopy cover, stem counts, and understory vegetation. Surveys were conducted in the spring and summer of 2010. It was found that batture birds, urban birds, and pooled birds all had greater species richness and abundance in the spring in areas with more canopy cover, higher stem counts, more understory vegetation, and distances closer to the batture. In the summer, batture birds had greater richness and abundance in areas with more canopy cover, higher stem counts, and more understory cover. This group of birds also had greater richness nearer the batture in the summer, but there were no significant abundance tests. Urban birds showed no preferences for any of the vegetative variables, but showed some tendency to have greater richness further away from the batture. Pooled birds did not significantly respond to any of the variables during the summer. Fifteen individual species of birds were also analyzed to see how they responded to the same variables.
112

Response of temperate forest birds to habitat change in central Chile

Thomson, Roberto F. January 2015 (has links)
Despite the long time since the introduction and spread of pine plantations in southern hemisphere countries there has been no study of the suitability of this exotic and novel type of vegetation on the native avifauna. This thesis aims to add understanding of this habitat replacement and its effects on the forest bird community. This research included a series of studies to assess the quality of mature pine plantations for the forest avifauna in comparison to what is in native forests. The first two studies determine the effects on the forest bird community of the fragmentation and replacement of native forest in a gradient of substitution. The results showed a direct relationship between level of substitution and loss of functional diversity, and that fragmentation predicts the bird assemblage in pine stands. The next two studies used data from an intensive ringing season to assess differences in the condition of populations inhabiting each habitat. Birds, in general, were found in better condition in native fragments than in pine plantations. Moreover, a despotic distribution was determined for a migrant species and a gradient in habitat quality was found in relation to proximity to native forest. The next two studies used information from a nest-box survey set in a gradient of sites with substitution of native forest. The results showed that the type of forest cover and their proportion in the landscape may affect the breeding performance of some species. Finally, in the last study I evaluated the foraging niche of bird species in each habitat. Compared with native forest, niche breath reduced while the niche overlap increased in pine plantations for most species. The results suggest that pine plantations are poor quality habitat for the bird community and that the substitution of native forests increases selective pressure.
113

The Integration of Google Maps into American Kestrel, Falco sparvarius, Nest Trail Programs

Harper, Dylan M. 01 May 2014 (has links)
American Kestrel Nest Box Programs have been established since the mid 1960’s. The population of American Kestrels (Falco sparverius) along nest box trails has decreased by 47 percent since their original implementation. There are existing technologies that can help in the location of prime kestrel habitat (open fields with conspicuous perching locations) along highways, which reduces the amount of labor in searching for new box locations. These technologies can also help increase the efficiency of monitoring and maintaining kestrel nest trail programs. This study provides an example of how Google Maps can be implemented into a kestrel trail and explains the multiple benefits of the integration.
114

Transcriptomic Response to Immune Challenge in Zebra Finch (Taeniopygia Guttata) Using RNA-SEQ

Scalf, Cassandra 01 April 2018 (has links)
Despite the convergence of rapid technological advances in genomics and the maturing field of ecoimmunology, our understanding of the genes that regulate immunity in wild populations is still nascent. Previous work to assess immune function has relied upon relatively crude measures of immunocompetence. However, with next-generation RNA-sequencing, it is now possible to create a profile of gene expression in response to an immune challenge. In this study, captive zebra finch (Taeniopygia guttata; adult males) were challenged with bacterial lipopolysaccharide (2 mg/Kg BW; dissolved in 0.9% saline) or vehicle (0.9% saline) to stimulate the immune system. Two hours after injection, birds were euthanized and hypothalami, spleen, and red blood cells (RBCs) were collected. Taking advantage of the fully sequenced genome of zebra finch, total RNA was isolated, sequenced, and partially annotated in these tissue/cells. The data show 628 significantly upregulated transcripts in the hypothalamus, as well as 439 and 121 in the spleen and RBCs, respectively, relative to controls. Also, 134 transcripts in the hypothalamus, 517 in the spleen, and 61 in the RBCs were significantly downregulated. More specifically, a number of immunity-related transcripts (e.g., IL-1β, RSAD2, SOCS3) were upregulated among tissues/cells. Additionally, transcripts involved in metabolic processes (APOD, LRAT, RBP4) were downregulated, suggesting a potential trade-off in expression of genes that regulate immunity and metabolism. Unlike mammals, birds have nucleated RBCs, and these results suggest a novel transcriptomic response of RBCs to immune challenge. Lastly, molecular biomarkers could be developed to rapidly screen bird populations by simple blood sampling in the field.
115

The red-tailed hawk on Sauvie Island, Oregon

Lien, Kevin J. 01 January 1982 (has links)
A study was undertaken to determine the abundance, distribution, perching heights, diets and territory sizes of Red-Tailed Hawks on Sauvie Island, Oregon. Sauvie Island supported a large wintering population of non-territorial Red-Tailed Hawks. The establishment of territories began around 10 January. Average perch height was found to be 14.2 m. Average perch height increased from fall to spring, corresponding-to the onset of the breeding season and to the onset of egg-laying and incubation. Voles (Microtus spp.) were the principal prey year-round, though waterfowl were more important in terms of biomass in the winter and early spring. Territory sizes on the Island ranged from .31 - 3.73 km squared The abundance of voles was assessed in different habitats within five Red-Tailed Hawk territories. Territory size was shown to be inversely correlated to the population density of voles. The implications of this finding for the type of territoriality exhibited by Red-Tailed Hawks is discussed, as are some proximate factors affecting habitat selection.
116

Factors influencing parental care and home range size of a monomorphic species, the Red-headed Woodpecker (Melanerpes erythrocephalus)

Walter, L. Abigail 01 January 2019 (has links)
Parental care in animals can be costly and is shared between both parents in many bird species. Not surprisingly, most studies of how parental care is shared between the sexes are in sexually dimorphic species, and much less in known about sexually monomorphic species where sex cannot be determined in the field. This has prevented a full understanding of parental care behaviors – which are intrinsically linked to fitness – in species such as the Red-headed Woodpecker (Melanerpes erythrocephalus) that is experiencing population declines throughout much of its range. In this study we assessed whether Redheaded Woodpecker brooding time, nestling provisioning rates, and nest cleaning rates vary as a function of parent sex, habitat type (savanna and closed canopy forest), brood size, nestling age, temperature and/or date. We recorded and analyzed 128 hours of high-quality video from 21 broods at Fort A.P. Hill, Virginia where this species is relatively abundant. We captured and color-banded Red-headed Woodpeckers, taking breast feather samples for genetic sexing, and determined brood size and chick age of nests using an extendable pole camera. Using generalized linear mixed models, we found the best predictor of nestling provisioning was an interaction between chick age and date; older chicks were fed more frequently in early summer (before 7 July) compared to late summer. The seasonal reduction in provisioning could be related to a reduction in resource availability, but whether or not provisioning in later nests affects nestling survival warrants further study. We found chick age and parent sex to be the best predictors in brooding models, with females brooding more when chicks are less than 10 days old and males being the only parent to enter the cavity after 10 days. Additionally, males almost exclusively remove fecal sacs from nests, highlighting an observational method to determine sex of breeding adults in the field. Such division of reproductive roles is similar to what is known for dimorphic woodpecker species and likely indicates energetic constraints due to the need for high parental investment from both sexes. Parental care is inextricably linked with habitat quality and home range size. Parents will travel to obtain the resources necessary to provision their young, and larger home ranges during the demanding nestling provisioning stage may indicate increased effort resulting from fewer available resources near the nest. We estimated home range sizes of 25 breeding adult Red-headed Woodpeckers using PinPoint GPS tags and 95% kernel density estimates (KDEs) with plug-in smoothing factors. We modeled the effects of habitat, sex, nest stage, date, and distance to nearest neighbor on home range estimates. Red-headed Woodpecker males have larger home ranges than females, and late summer home ranges are smaller than those measured before 7 July. More study is needed to determine if sex or date is a stronger factor on home range, given our naive sampling which resulted in more females sampled in late summer and observations that did not continue to the end of the breeding season (late August). Since we found date to be an influential factor to both provisioning rate and home range size, it is possible that seasonal resource changes are an important, unstudied factor related to nationwide declines of this species.
117

RED COATS AND WILD BIRDS: MILITARY CULTURE AND ORNITHOLOGY ACROSS THE NINETEENTH-CENTURY BRITISH EMPIRE

GREER, KIRSTEN ALETTA 02 September 2011 (has links)
“Red coats and wild birds: military culture and ornithology across the nineteenth-century British Empire” investigates the intersections between British military culture and the practices and ideas of ornithology, with a particular focus on the British Mediterranean. Considering that British officers often occupied several imperial sites over the course of their military careers, to what extent did their movements shape their ornithological knowledge and identities at “home” and abroad? How did British military naturalists perceive different local cultures (with different attitudes to hunting, birds, field science, etc.) and different local natures (different sets of birds and environments)? How can trans-imperial careers be written using not only textual sources (for example, biographies and personal correspondence) but also traces of material culture? In answering these questions, I centre my work on the Mediterranean region as a “colonial sea” in the production of hybrid identities and cultural practices, and the mingling of people, ideas, commodities, and migratory birds. I focus on the life geographies of four military officers: Thomas Wright Blakiston, Andrew Leith Adams, L. Howard Lloyd Irby, and Philip Savile Grey Reid. By the mid-nineteenth century, the Mediterranean region emerged as a crucial site for the security of the British “empire route” to India and South Asia, especially with the opening of the Suez Canal in 1869. Military stations served as trans-imperial sites, connecting Britain to India through the flow of military manpower, commodities, information, and bodily experiences across the empire. By using a “critical historical geopolitics of empire” to examine the material remnants of the “avian imperial archive,” I demonstrate how the practices and performances of British military field ornithology helped to: materialize the British Mediterranean as a moral “semi-tropical” place for the physical and cultural acclimatization of British officers en route to and from India; reinforce imperial presence in the region; and make “visible in new ways” the connectivity of North Africa to Europe through the geographical distribution of birds. I also highlight the ways in which the production of ornithological knowledge by army officers was entwined with forms of temperate martial masculinity. / Thesis (Ph.D, Geography) -- Queen's University, 2011-09-02 09:17:17.931
118

Evaluating avian communities of the Blanco River Valley using occupancy modeling and landowner conducted surveys /

Korn, Jennifer Marie, January 2008 (has links)
Thesis (M.S.)--Texas State University-San Marcos, 2008. / Vita. Appendix: leaves 23-31. Includes bibliographical references (leaves 32-33). Also available on microfilm.
119

Wind drift and the use of radar, acoustics, and Canadian Migration Monitoring Network methods for monitoring nocturnal passerine migration /

Peckford, Michael L. January 1900 (has links)
Thesis (M.Sc.)--Acadia University, 2006. / Includes bibliographical references (leaves 73-79). Also available on the Internet via the World Wide Web.
120

Speciation genomics and morphological evolution in an extraordinary avian radation, the Lonchura munias of New Guinea and Australia

Stryjewski, Katherine Faust 28 November 2015 (has links)
Speciation, the evolution of morphologically, behaviorally and/or ecologically distinct lineages from a common ancestor, is the fundamental process generating biodiversity. The rapidly developing field of speciation genomics is challenging traditional views of speciation as a gradual, genome-wide process, and highlighting the role of divergent natural selection in the speciation process. This study investigates morphological evolution and the genomic architecture of speciation in a clade of 12 "munias" in the genus Lonchura, one of the most extraordinary cases of recent and rapid diversification in birds. With a diversity of plumage patterns and replicate examples of closely related species living in sympatry, this group is ideally suited
for addressing fundamental questions about the genomics of speciation. In this study, I (1) test for evidence of character displacement between sympatric species using quantitative measurements of plumage coloration and morphology; (2) examine the structure of genome-wide variation using ddRAD-seq (double-digest Restriction Site Associated DNA sequencing); and (3) investigate the genomic structure of divergence using whole-genome sequencing. I find some evidence for character displacement, particularly in morphometrics and crown coloration. There is also a trend, however, for sympatric species to be more similar in coloration than allopatric species, particularly those that have come into contact more recently. Analysis of 7,043 ddRAD-seq loci reveals evidence of introgression among sympatric populations, with overall genomic variation corresponding more closely to geography than species identity. There is also substantial heterogeneity in genetic structure among mitochondrial, autosomal, and Z-linked markers. Finally, whole-genome sequencing reveals low overall genomic divergence while pinpointing "islands of differentiation" that exhibit elevated divergence between species. Two of these islands overlap genes known to be associated with coloration—Agouti signaling protein (ASIP) and Kit ligand (KITLG)—and allelic variation at these genes is associated with phenotypic traits. I also find evidence of a ~26 million base pair inversion on the Z chromosome, which groups the focal species differently than genome-wide variation. A strongly mosaic pattern of population structure among genomic regions supports a genic view of speciation, in which a small fraction of the genome is involved in the initial divergence of species.

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