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Articles 1 - 30 of 41
Full-Text Articles in Ornithology
Spatial Conservation Planning In The Southeastern United States: Alignments And Opportunities, Bradly Stewart Thornton
Spatial Conservation Planning In The Southeastern United States: Alignments And Opportunities, Bradly Stewart Thornton
Theses and Dissertations
Conservation managers and planners need the ‘best available science’ to support robust and defensible decisions, ensuring that public resources are appropriately allocated. Spatial planning products and decision-support tools developed for this purpose should enable partner organizations to achieve focus, coordination, and increased effectiveness in their investments and actions. Whereas conservation partnerships have historically created distinct planning tools, there is increasing interest for improved coordination, communication, and unifying biological datasets to improve the cohesiveness of regional management activities. We sought to inform spatial conservation planning efforts in the southeastern United States through the development of species distribution models for focal avian …
Quantifying Insect Emergence In Tidal Freshwaters And The Importance Of Aquatic Prey In Wetland-Dependent Songbird Diet, Samantha L. Rogers
Quantifying Insect Emergence In Tidal Freshwaters And The Importance Of Aquatic Prey In Wetland-Dependent Songbird Diet, Samantha L. Rogers
Theses and Dissertations
Insectivorous birds and their arthropod prey are experiencing widespread population declines, driven largely by anthropogenic disturbance and climate change. For wetland-dependent insectivores that consume a mixture of terrestrial and aquatic insects, understanding the availability, consumption, and nutritional qualities of aquatic diet subsidies is important for conservation. I use prothonotary warblers (Protonotaria citrea) as a model species throughout this work, because their breeding season aligns with aquatic insect emergence and they include aquatic insects when provisioning nestlings. In the first chapter, I estimate aquatic insect emergence from tidal freshwaters, which are understudied compared to nontidal systems. Using continuous field …
The Role Of Nest Location On The Reproductive Success Of Piping Plovers Breeding At Rockaway Beach, New York, Clara I.D. Arndtsen
The Role Of Nest Location On The Reproductive Success Of Piping Plovers Breeding At Rockaway Beach, New York, Clara I.D. Arndtsen
Theses and Dissertations
The study’s goal was to learn what aspects of the piping plover experience affect reproductive outcomes at Rockaway Beach Endangered Species Nesting Area. Nest location was found to help predict reproductive success. Nests further from American oystercatcher nests were likely to fledge more chicks. Reproductive success was low in 2021.
Nesting Ecology Of Wood Ducks And Other Cavity-Nesting Ducks In Mississippi, Justin Taylor Gibson
Nesting Ecology Of Wood Ducks And Other Cavity-Nesting Ducks In Mississippi, Justin Taylor Gibson
Theses and Dissertations
Man-made nest boxes are surrogate nest sites widely used by waterfowl managers in North America to propagate free-ranging Wood Ducks (Aix sponsa) and other cavity-nesting waterfowl. I monitored 129 and 174 nest boxes in 2020 and 2021, respectively, at Noxubee National Wildlife Refuge and York Woods, Mississippi. I evaluated site-specific biotic and abiotic factors that were potentially influential on nest survival of Wood Ducks and general nesting ecology and apparent nest success of Black-bellied Whistling Ducks (Dendrocygna autumnalis) and Hooded Mergansers (Lophodytes cucullatus). Daily survival rate of Wood Ducks was negatively influenced by increasing encroaching vegetation at Noxubee NWR and …
Evaluating Population Genetic Structure And Potential Genomic Signals Of Natural Selection In A Migratory Songbird (Protonotaria Citrea), Tyler A. Hohenstein
Evaluating Population Genetic Structure And Potential Genomic Signals Of Natural Selection In A Migratory Songbird (Protonotaria Citrea), Tyler A. Hohenstein
Theses and Dissertations
In this study I attempted to further resolve the population genetic structure in the Prothonotary Warbler (Protonotaria citrea), and conducted an outlier SNP analysis and exploratory gene ontology analysis to investigate potential ongoing natural selection in the species. This analysis of population structure confirms previous work by DeSaix et al. (2019), where weak population structure was observed between eastern sites along the Atlantic Coastal Plain, and western sites in the Mississippi Alluvial Valley, possibly due to a genetic discontinuity across the Appalachian Mountains. I conducted two forms of outlier SNP analyses, a principal component analysis (PCA)-based approach to identify SNPs …
Duet Phonology And Syntax Of The Red-Crowned Parrots In South Texas, Abigail Pozulp
Duet Phonology And Syntax Of The Red-Crowned Parrots In South Texas, Abigail Pozulp
Theses and Dissertations
Bird behavioral interaction systems show a preference for temporal precision. This preference is exemplified in the way many species avoid masking of vocal signals. Antiphonal duetting in songbirds suggest that overlapping notes are a sign of poor temporal coordination which can signify a weak pairbond, a possible cue for conspecifics seeking to usurp territories or mates. However, parrots (Psittacidae) are accomplished yet understudied duetters in nature. I recorded antiphonal duets produced by a wild population of red-crowned parrots (Amazona viridigenalis) in Brownsville, Texas. Temporal and acoustic variation of signals was assessed within and across a sample of mated …
Home Range Dynamics And Juvenile Dispersal Of Gray Hawks In The Lower Rio Grande Valley, Michael Stewart
Home Range Dynamics And Juvenile Dispersal Of Gray Hawks In The Lower Rio Grande Valley, Michael Stewart
Theses and Dissertations
Using GPS-GSM transmitters I determined when 14 juvenile Gray Hawks (Buteo plagiatus) in the Lower Rio Grande Valley of Texas fledged from their natal areas and how far they traveled once they dispersed. These transmitters also allowed me to calculate home range sizes for 22 adults. Additionally, with the GPS-GSM transmitters and 15 VHF transmitters, I discovered that adult Gray Hawks in the study area remained in their territories year-round. Home range sizes were calculated using the minimum convex polygon estimator, the estimation of kernel home-range, and the estimation of kernel Brownian bridge home-range. The same three methods allowed me …
Effects Of Early Corticosterone Treatment On Vocal Babbling In Wild Green-Rumped Parrotlets (Forpus Passerinus), Celia Rose Mclean
Effects Of Early Corticosterone Treatment On Vocal Babbling In Wild Green-Rumped Parrotlets (Forpus Passerinus), Celia Rose Mclean
Theses and Dissertations
The stress axis of the endocrine system allows for animals to respond to environmental stressors in contextually appropriate ways. Elevated levels of the stress hormone corticosterone (CORT) in male songbirds can result in compromised song learning ability. Parrots form a sister group to songbirds, but it is unknown whether CORT affects vocal development in parrots. The goal of this study was to assess the effects of CORT supplements in green-rumped parrotlets (Forpus passerinus), a free-ranging parrot species in Venezuela. Bouts of vocal babbling were extracted from nest box videos and analyzed. CORT supplementation resulted in differences in babbling …
Searching For Gold: Using A Novel Land Cover Classification To Identify Multiscale Drivers Of Site Occupancy By A Flagship Species For Early-Successional Habitat Conservation, Baron Lin
Theses and Dissertations
Understanding habitat selection at multiple scales is an important step in guiding conservation programs and reversing species declines. This, however, is difficult for species that occupy early-successional habitats (ESH) due to a lack of accurate representation of shrub cover in publicly available land cover data. The Golden-winged Warbler (Vermivora chrysoptera; GWWA) is a threatened species of conservation concern and a flagship for ESH conservation. We used a novel, LIDAR-derived land cover classification that accurately identifies shrubs at a fine resolution (1m) to investigate how habitat composition and configuration influence GWWA site occupancy. We aggregated this same land cover …
Tracing The Human-Avian Relationship In Iceland, Melanie Sua
Tracing The Human-Avian Relationship In Iceland, Melanie Sua
Theses and Dissertations
An in-depth investigation explores the history of birds in Iceland and the interaction between birds and humans from the 9th through the 19th century, with the help of archaeological evidence, traditional and historical materials.
Organizational Effects Of Exogenous Corticosterone On Vocal Development In A Wild Parrot, Rory Eggleston
Organizational Effects Of Exogenous Corticosterone On Vocal Development In A Wild Parrot, Rory Eggleston
Theses and Dissertations
Songbirds learn songs during a plastic phase in vocal development, similar to human vocal babbling. Research has focused on male song learning, a process influenced by gonadal steroids. Like humans, parrots are very plastic vocal learners and both sexes learn vocalizations throughout life. It is unclear how the endocrine system mediates environmental information with developing phenotypes in parrots. Corticosterone (CORT) is a sex-neutral hormone that can affect cognitive development, but its role in vocal development has not been experimentally tested in wild parrots. I quantified vocal babbling from nestling Green-rumped Parrotlets (Forpus passerinus) recorded in Venezuela. Nestlings received oral CORT-oil …
The Whelming Sea, Sean Hanley
The Whelming Sea, Sean Hanley
Theses and Dissertations
The Whelming Sea is a thirty-minute experimental documentary that reveals the moments of entanglement between three animals living along the Mid-Atlantic shoreline; curious humans, spawning horseshoe crabs, and migratory shorebirds. Working from the realm of multispecies ethnography, the film shifts the subjective positioning of the viewer between the human and nonhuman to suggest the complexity of our enmeshed experience. In the face of this current era of mass extinction, the film explores the limitations and poetic possibilities of scientific encounters with the lives of others.
Social Influences On Vocal Development In A Wild Parrot, Caleb Michael Mand Arellano
Social Influences On Vocal Development In A Wild Parrot, Caleb Michael Mand Arellano
Theses and Dissertations
The Social Intelligence Hypothesis (SIH) proposes that navigating complex societies requires increased neural processing to monitor shifting relationships. SIH evolutionary focus of brain size variation in adults originally ignored the developmental frameworks leading to increased sociality. I studied the ontogeny of early sibling interactions in wild Green‐rumped Parrotlets (Forpus passerinus) in a Venezuelan population that exhibited large variation in brood size and engaged in elaborate social interactions and complex social learning during nestling development. To test if nests of varying brood sizes exhibit differences in social complexity, I quantified the number and strength of sibling play partnerships, as a proxy …
Factors Influencing Parental Care And Home Range Size Of A Monomorphic Species, The Red-Headed Woodpecker (Melanerpes Erythrocephalus), L. Abigail Walter
Factors Influencing Parental Care And Home Range Size Of A Monomorphic Species, The Red-Headed Woodpecker (Melanerpes Erythrocephalus), L. Abigail Walter
Theses and Dissertations
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 …
Impacts Of Habitat Attributes And Community Gardens On Urban Bird Communities, Samuel Glenn Ortiz
Impacts Of Habitat Attributes And Community Gardens On Urban Bird Communities, Samuel Glenn Ortiz
Theses and Dissertations
The Rio Grande Valley of Southern Texas is a major agricultural region yet has some of the highest hunger rates in the USA. Urbanization and agriculture affect biodiversity, which is well studied, but little is known about how agriculture affects biodiversity in urban areas. We investigated how different urban attributes, including those related to urban farming, impact bird communities in Brownsville and Harlingen, TX, and compared sites that have community gardens to those that do not. To study three key urban habitat characteristics, we identified sites that exhibited all possible combinations of these factors, quantified land cover classes related to …
Factors Of Annual Reproductive Success In North American Barn Swallows (Hirundo Rustica Erythrogaster) In Shared Greenspace, Joseph Czeisel
Factors Of Annual Reproductive Success In North American Barn Swallows (Hirundo Rustica Erythrogaster) In Shared Greenspace, Joseph Czeisel
Theses and Dissertations
This study examined three metrics related to barn swallow reproductive success in shared greenspace. Earlier nesting dates were positively related to reproductive output and survival rate. Anthropogenic disturbance was not found to influence productivity. The distance of nests inside structures predicted survival rate. The monitoring of additional seasons is recommended.
Slave To The Rhythm: Variation In The Acoustic Signaling Of Picoides Woodpeckers, Alex Baer
Slave To The Rhythm: Variation In The Acoustic Signaling Of Picoides Woodpeckers, Alex Baer
Theses and Dissertations
We explored rhythmic variation in acoustic signals by geography across four species of Picoides woodpeckers. We hypothesized that there would be an effect of geographic location on the cadence of drums and rattle-type calls. No significant effect was observed. However, drum cadence was observed to significantly impact conspecific recognition in playbacks.
Using A Custom Landscape Classification To Understand The Factors Driving Site Occupancy By A Rapidly Declining Migratory Songbird, Elizabeth K. Schold
Using A Custom Landscape Classification To Understand The Factors Driving Site Occupancy By A Rapidly Declining Migratory Songbird, Elizabeth K. Schold
Theses and Dissertations
Land cover classifications are useful in a broad range of ecological applications, yet publicly available classifications are not always useful for the needs of specific projects. Custom classifications are always a possibility, however, they can be financially or computationally out of reach for many researchers. Here we present a custom 1m resolution land cover classification created using freely available imagery and a random forest classification approach. This classification detected shrub cover more accurately and at a finer resolution than previous classifications. With the creation of this map, we were then able to examine landscape factors influencing occupancy dynamics of the …
Migratory Patterns And Population Genetic Structure In A Declining Wetland-Dependent Songbird, Matthew G. Desaix
Migratory Patterns And Population Genetic Structure In A Declining Wetland-Dependent Songbird, Matthew G. Desaix
Theses and Dissertations
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 …
The Vocal Babbling Behavior And Its Sibling Effects In A Wild Parrot, Tatiana Dolgushina
The Vocal Babbling Behavior And Its Sibling Effects In A Wild Parrot, Tatiana Dolgushina
Theses and Dissertations
Vocal learning is a rare trait in the animal kingdom, defined as the sensorimotor imitation of sounds, and is only found in select groups of birds and mammals. Parrots are a behaviorally complex group of birds, famous for their ability to mimic social companions, but how they develop this ability in the wild has received little attention. The vocal learning period consists of a complex vocal babbling stage, a crucial developmental precursor for imitation of adult vocalizations in humans and songbirds, but has not been described in any of the 360+ parrot species. This project quantifies potential individual variation in …
Foraging Patterns And Population Density Of The Buff-Bellied Hummingbird (Amazilia Yucatanensis) In Hidalgo County, Tx, Megan I. Villarreal
Foraging Patterns And Population Density Of The Buff-Bellied Hummingbird (Amazilia Yucatanensis) In Hidalgo County, Tx, Megan I. Villarreal
Theses and Dissertations
The objective of this investigation was to examine the foraging patterns and population density of the Buff-bellied Hummingbird (Amazilia yucatanensis ) in Hidalgo County, TX. Previous studies showed that hummingbirds use flowers displaying traditional bird pollination (ornithophilous) characteristics: reddish coloration, tubular corolla, and extended anthers. Observation sessions noted type and frequency of flowering species utilized for nectar, characteristics, and number of individuals seen in each area. Amazilia yucatanensis showed higher use of ornithophilous flowers. Significant results found: f-ratio 5.45 > p-value (0.05) 3.24. Two highly utilized species showed the expected 20–40% sucrose content expected in ornithophilous flowers. Population density per …
Agricultural Conservation Buffers For Breeding Grassland Birds In Eastern Mississippi, Heidi Lynn Adams
Agricultural Conservation Buffers For Breeding Grassland Birds In Eastern Mississippi, Heidi Lynn Adams
Theses and Dissertations
Periodic disturbance in CP33 habitat buffers is required to maintain early-successional plant communities for grassland birds. However, effects of disturbance on habitat suitability and nesting success of grassland birds are unknown. Furthermore, the grassland bird community and reproductive performance in CP33 habitat buffers may be influenced by the landscape context (e.g., edge habitat, surrounding land cover). My objectives for this study were to determine how periodic disturbance and the agricultural landscape mosaic influence the breeding grassland bird community in buffers, and how these same factors influence grassland bird nesting success and density in buffers. Data collected during line-transect surveys conducted …
Aspects Of Bald Eagle Winter Behavior In Rush Valley Utah: A Telemetry Study, Neil B. Sabine
Aspects Of Bald Eagle Winter Behavior In Rush Valley Utah: A Telemetry Study, Neil B. Sabine
Theses and Dissertations
The diurnal behavior and nocturnal roosting patterns of 28 bald eagles outfitted with tail-mounted radios were investigated in Rush Valley, Utah between January and March 1982-1984. Casting analysis and feeding observations indicated the principal food source was jackrabbit carrion. Jackrabbit availability declined from 1982 to 1984 and eagles responded by; 1) roosting closer to feeding sites, 2) shifting from canyon to valley roosts, 3) arriving later at and departing earlier from roosts, 4) decreasing diurnal activity, and 5) decreasing residence time. Foraging efficiency appeared to be maximized by experienced eagles using familiar feeding areas and by naive birds monitoring their …
Utilization Of Nest Boxes By Birds In Three Vegetational Communities With Special Reference To The American Kestrel (Falco Sparverius), Laurence Barrett Mcarthur
Utilization Of Nest Boxes By Birds In Three Vegetational Communities With Special Reference To The American Kestrel (Falco Sparverius), Laurence Barrett Mcarthur
Theses and Dissertations
This study was designed to determine if, by providing artificial nest sites, a raptorial predator could be attracted into an area where suitable sites are limited. The American Kestrel (Falco sparverius) was a common species in the area and nest boxes designed for their use were placed in three vegetational types in western Utah and eastern Nevada. Seventy boxes were available in 1975 and 110 in 1976. Kestrels nested both years in the salt-desert shrub community but were absent from the pinyon-juniper and riparian areas. Four other bird species nested in the latter two areas, however. In 1975 the nesting …
The Snowy Egret (Egretta Thula Brewsteri) A Life History Study At Utah Lake With Comments On The Subspecies Status, Gerald Leigh Gunnell
The Snowy Egret (Egretta Thula Brewsteri) A Life History Study At Utah Lake With Comments On The Subspecies Status, Gerald Leigh Gunnell
Theses and Dissertations
This study was conducted to augment the limited information available regarding the Snowy Egret in the Utah Lake area of Utah. Field observations included the following: nesting habits; egg and clutch sizes; sexual, defense, and feeding behaviors. Analysis was made of the distinguishing subspecies characteristics (culmen, tarsus, and wing length) of the Snowy Egrets and of the distribution of the birds. Field observations showed that growth measurements of the young varied from 16.75 g at hatching to 260.58 g after 17 days. Culmen and tarsus measurements were 15.41 mm and 14.12 mm to 53.18 mm and 62.18 mm, respectively, after …
Habitat Partitioning In A Community Of Passerine Birds, Robert C. Whitmore
Habitat Partitioning In A Community Of Passerine Birds, Robert C. Whitmore
Theses and Dissertations
Habitat partitioning was studied in a community of passerine birds in the Virgin River Valley of southwestern Utah. Ten habitat structure variables were measured for each of 24 species of passerine birds and several multivariate statistical techniques were used to determine the extent of habitat partitioning. Ordinations of species distributions along known environmental gradients were constructed using Principal Component Analysis and Stepwise Discriminant Analysis. Stepwise Discriminant Analysis was also used to determine which habitat variables were important in species separation. It was found that percent canopy cover was the most important variable. Two hundred seventy six pairs of species were …
Raptor Temperature Regulation And Energetics, James Arthur Mosher
Raptor Temperature Regulation And Energetics, James Arthur Mosher
Theses and Dissertations
A review of energetics studies of raptorial species introduces four separate studies of temperature regulation by raptors. Golden Eagle (Aquila chrysaetos) nest site selection, as influenced by direction of exposure, is discussed. The data show strong directional preferences to the NNW by southern populations and SSE by northern populations. The tarsometatarsus is shown to have a thermoregulatory function in large falcons, and adaptations of this mechanism to varied habitats are examined. Color phase in Screech Owls (Otus asio) is shown to be related to metabolic differences that may explain the distributions of the color morphs. Development of thermoregulation in Flammulated …
Ecology Of The Ferruginous Hawk (Buteo Regalis) In Central Utah Population Dynamics And Nest Site Selection, Neil D. Woffinden
Ecology Of The Ferruginous Hawk (Buteo Regalis) In Central Utah Population Dynamics And Nest Site Selection, Neil D. Woffinden
Theses and Dissertations
Research was conducted to determine the effect of prey numbers on the nesting success of the Ferruginous Hawk (Buteo regalis). Conditions associated with nest site selection were also established. Frequent visits were made to active nests to determine clutch sizes, hatching dates and fledging success. Prey remains were collected from nests and analyzed. Kilometer square transects were made throughout the study area in 1974 to determine jackrabbit densities. A drastic decline in numbers of Ferruginous Hawks occurred. The number of young fledged also declined throughout the study while nestling mortality increased. Jackrabbit numbers were high in 1972 and then declined …
Biology Of Northern Bald Eagles (Haliaeetus Leucocephalus Alascanus) On Amchitka Island, Alaska, Steven K. Sherrod
Biology Of Northern Bald Eagles (Haliaeetus Leucocephalus Alascanus) On Amchitka Island, Alaska, Steven K. Sherrod
Theses and Dissertations
Bald Eagles on Amchitka Island, Alaska, were studied from 1969-1972. From 1970-1972 the population averaged 214.6 eagles. The average ration was 66% adults to 34% subadults. The eagles move to and from the island in relation to significant food sources (especially the garbage dump). An increase in active nests occurred from 1969-1972 due to an increase in food. The average percentage of nests containing young from 1970-1972 was 71.28%. During these three years, the average number of young known in a nest per nesting attempt was 1.24, and the average number of young known in a nest per nest containing …
Nesting Ecology Of The Double-Crested Cormorant (Phalacrocorax Auritus Auritus) On Utah Lake, Ronald M. Mitchell
Nesting Ecology Of The Double-Crested Cormorant (Phalacrocorax Auritus Auritus) On Utah Lake, Ronald M. Mitchell
Theses and Dissertations
Research on the nesting of the Double-crested Cormorant (Phalacrocorax auritus auritus) was undertaken to determine the nesting ecology of the bird on Utah Lake, Utah County, and the possible effects that diking Provo Bay would have on the cormorants breeding there. In 1973, two colonies in Provo Bay were visited weekly to determine laying dates, incubation period, clutch size, and hatching dates. Another colony, located on the dike of the Geneva Steel Reservoir, was visited daily during the spring and summer of 1973. At this colony, egg-laying occurred from 13 April to 17 May. The average clutch size was 3.8, …