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Articles 151 - 180 of 264
Full-Text Articles in Ornithology
Across-Year Social Stability Shapes Network Structure In Wintering Migrant Sparrows, Daizaburo Shizuka, Alexis S. Chaine, Jennifer Anderson, Oscar Johnson, Inger Marie Laursen, Bruce E. Lyon
Across-Year Social Stability Shapes Network Structure In Wintering Migrant Sparrows, Daizaburo Shizuka, Alexis S. Chaine, Jennifer Anderson, Oscar Johnson, Inger Marie Laursen, Bruce E. Lyon
School of Biological Sciences: Faculty Publications
Migratory birds often form flocks on their wintering grounds, but important details of social structure such as the patterns of association between individuals are virtually unknown. We analysed networks of co-membership in short-term flocks for wintering golden-crowned sparrows (Zonotrichia atricapilla) across three years and discovered social complexity unsuspected for migratory songbirds. The population was consistently clustered into distinct social communities within a relatively small area (~ 7 ha). Birds returned to the same community across years, with mortality and recruitment leading to some degree of turnover in membership. These spatiotemporal patterns were explained by the combination of space …
The Foraging Behaviors And Decision-Making Strategies Of Overwintering Red-Tailed Hawks (Buteo Jamaicensis) And American Kestrels (Falco Sparverius) In Relation To Prey Density And Patch-Site Characteristics In Northeastern Arkansas, Melissa Marie Bobowski
Student Theses and Dissertations
I observed the wintering foraging behaviors of Red-tailed Hawks (Buteo jamaicensis) and American Kestrels (Falco sparverius) to determine the efficiency of their foraging strategies in relation to prey density and patch-site characteristics. The three cover-types (i.e., short rice stubble, soybean stubble, and fallow areas and roadsides) differed in densities of small mammals and vegetation cover. Cover-type was the most important predictor for the probability of making an attempt at prey for both species with the greatest probability at attempting was in fallow roadsides. Perch-type only influenced the probability of being successful at capturing a prey item for Red-tailed hawks with …
The Passive Perching Mechanism In Passeriformes Birds, Deena Ahmed Elsahy
The Passive Perching Mechanism In Passeriformes Birds, Deena Ahmed Elsahy
Undergraduate Honors Thesis Collection
Passeriformes, or perching birds and songbirds, are an order of birds that includes crows, jays, starlings, wrens, cardinals, finches and many other species. It has been suggested that these birds are able to passively perch due to a tendon locking mechanism. This mechanism allows them to rest for hours in trees without falling. When the bird's foot is placed on a perch, the weight of the bird causes the tendons to pull, thus closing the toes around the perch. However, there is currently much debate about whether the mechanism is entirely passive. Recent studies argue that the mechanism must be …
Survival, Abundance, And Geographic Distribution Of Temperate-Nesting Canada Geese (Branta Canadensis) In Arkansas, Margaret Eliese Ronke
Survival, Abundance, And Geographic Distribution Of Temperate-Nesting Canada Geese (Branta Canadensis) In Arkansas, Margaret Eliese Ronke
Graduate Theses and Dissertations
Temperate-nesting Canada geese in Arkansas have grown in abundance and range since reintroduction in the 1980s. The Arkansas Game and Fish Commission uses harvest and other methods to maintain the population at desired levels. However, continued management of temperate-nesting geese requires knowledge of the population's demographics and current range to help establish quantifiable management goals.
To assess the need and effect of changing hunting regulations, survival and recovery rates and abundance were estimated for this population. Annual survival rates of temperate-nesting Canada geese banded and recovered in Arkansas from 2005 to 2011 were estimated using the Burnham joint live-dead recovery …
Variable Facial Plumage In Juvenile Cliff Swallows: A Potential Offspring Recognition Cue?, Allison E. Johnson, Steven Freedberg
Variable Facial Plumage In Juvenile Cliff Swallows: A Potential Offspring Recognition Cue?, Allison E. Johnson, Steven Freedberg
School of Biological Sciences: Faculty Publications
Although the ability to recognize related offspring is essential in the evolution of social behavior, the cues that birds use to identify their own offspring are not fully understood. The Cliff Swallow (Petrochelidon pyrrhonota) is a highly social species that nests in large colonies and exhibits a high incidence of both conspecific brood parasitism and extrapair fertilization, behaviors that can potentially lead to parents investing energy and resources in unrelated offspring, which reduces the parents’ genetic fitness. Because parents continue to feed offspring after they leave the nest, parents also risk investing in unrelated offspring by misidentifying their …
As The Egg Turns: Monitoring Egg Attendance Behavior In Wild Birds Using Novel Data Logging Technology, Scott A. Shaffer, Corey Clatterbuck, Emma Kelsey, Alex Naiman, Lindsay Young, Eric Vanderwerf, Pete Warzybok, Russell Bradley, Jaime Jahncke, Geoff Bower
As The Egg Turns: Monitoring Egg Attendance Behavior In Wild Birds Using Novel Data Logging Technology, Scott A. Shaffer, Corey Clatterbuck, Emma Kelsey, Alex Naiman, Lindsay Young, Eric Vanderwerf, Pete Warzybok, Russell Bradley, Jaime Jahncke, Geoff Bower
Faculty Publications, Biological Sciences
Egg turning is unique to birds and critical for embryonic development in most avian species. Technology that can measure changes in egg orientation and temperature at fine temporal scales (1 Hz) was neither readily available nor small enough to fit into artificial eggs until recently. Here we show the utility of novel miniature data loggers equipped with 3-axis (i.e., triaxial) accelerometers, magnetometers, and a temperature thermistor to study egg turning behavior in free-ranging birds. Artificial eggs containing egg loggers were deployed in the nests of three seabird species for 1–7 days of continuous monitoring. These species (1) turned their eggs …
Relative Importance Of Male Song On Female Mate Selection In The Zebra Finch (Taeniopygia Guttata), Casey Sprague
Relative Importance Of Male Song On Female Mate Selection In The Zebra Finch (Taeniopygia Guttata), Casey Sprague
Scripps Senior Theses
In the zebra finch (Taeniopygia guttata), song and its social context play an important role in female mate selection. The song of the zebra finch is unique in that it can only be produced by males, which makes the species ideal for analyzing the components of male song that influence female song preference and mate selection. There are three consistent features of zebra finch song that affect female mate preference: 1) the amount of time a male sings, 2) the size and complexity of his song repertoire, and 3) the structural conformation to species or population norms (reviewed …
Experimental Analysis Of Nest-Site Choice And Its Relationship To Nest Success In An Open-Cup–Nesting Passerine, Sarah Cancellieri, Michael T. Murphy
Experimental Analysis Of Nest-Site Choice And Its Relationship To Nest Success In An Open-Cup–Nesting Passerine, Sarah Cancellieri, Michael T. Murphy
Biology Faculty Publications and Presentations
Nest placement presumably reflects selection for secure sites to minimize failure. Most tests of this hypothesis, however, have failed to support it. We used artificial nests (ARTs) to experimentally evaluate nest-site-choice behavior by an open-cup–nesting bird, the Eastern Kingbird (Tyrannus tyrannus). In 2010 and 2011, we placed ARTs in trees in the riparian zone at Malheur National Wildlife Refuge, Oregon, USA, to test whether (1) characteristics describing the physical location in trees of used and unused ARTs differed, (2) used ART sites more closely resembled naturally chosen sites, (3) successful natural nests (NATs) and successful ARTs were similarly …
Painted Redstarts In South Texas, 2013-2014, Timothy Brush
Painted Redstarts In South Texas, 2013-2014, Timothy Brush
School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)
No abstract provided.
Reproductive Isolation And Cryptic Introgression In A Sky Island Enclave Of Appalachian Birds, Gene D. Sattler, Michael J. Braun
Reproductive Isolation And Cryptic Introgression In A Sky Island Enclave Of Appalachian Birds, Gene D. Sattler, Michael J. Braun
Faculty Publications and Presentations
Reproductive isolation is central to the speciation process, and cases where the strength of reproductive isolation varies geographically can inform our understanding of speciation mechanisms. Although generally treated as separate species, Black-capped chickadees (Poecile atricapillus) and Carolina chickadees (P. carolinensis) hybridize and undergo genetic introgression in many areas where they come into contact across the eastern United States and in the northern Appalachian Mountains. The Great Smoky Mountains harbor the last large breeding population of atricapillus in the southern Appalachians, isolated from the species’ main range by nearly 200 km. This population is believed to be reproductively isolated from local …
Residential Edges As Ecological Traps: Postfledgling Survival Of A Ground-Nesting Passerine In A Forested Urban Park, Amy A. Shipley, Michael T. Murphy, Adam H. Elzinga
Residential Edges As Ecological Traps: Postfledgling Survival Of A Ground-Nesting Passerine In A Forested Urban Park, Amy A. Shipley, Michael T. Murphy, Adam H. Elzinga
Biology Faculty Publications and Presentations
Substantial offspring mortality can occur during the postfledging period of birds, but few postfledging survival studies have been conducted within the context of habitat suitability. We conducted a 2-year radiotelemetry study of Spotted Towhee (Pipilo maculatus) reproductive success and fledgling survival in a 24-ha forested park in a residential area of Lake Oswego, Oregon. In corroboration of previous research on this species, we found (1) that Spotted Towhees nested closer to the edge between the park and residential neighborhoods than expected by chance, and (2) that pairs nesting near edges produced the largest and most offspring. However, fates were reversed …
Investigating The Function Of The Mold Specific Gene M46, In The Pathogenic Dimorphic Fungus Histoplasma Capsulatum, Davida Lashaundra Crossley
Investigating The Function Of The Mold Specific Gene M46, In The Pathogenic Dimorphic Fungus Histoplasma Capsulatum, Davida Lashaundra Crossley
Dissertations
Histoplasma capsulatum (Hc) is a dimorphic fungus that is the etiologic agent for the respiratory infection histoplasmosis. The fungus is found in the environment in contaminated soils of birds and bat excreta as a multi-cellular saprophytic mold. Once the soil is disturbed, spores are released and are inhaled into the lungs. In the lungs, the fungus converts to uni-cellular parasitic yeast (Maresca & Kobayashi, 1989). The conversion from mold to yeast is a requirement for pathogenesis. Previously, several mold specific genes have been isolated by our laboratory from a subtracted cDNA library. One such gene, is M46. M46 is a …
Interrelationships Between Testosterone, Aggression, And Parental Care Of A Temperate-Zone, Resident Songbird, The Northern Cardinal (Cardinalis Cardinalis), Margaret Susan Devries
Interrelationships Between Testosterone, Aggression, And Parental Care Of A Temperate-Zone, Resident Songbird, The Northern Cardinal (Cardinalis Cardinalis), Margaret Susan Devries
Dissertations
Interrelationships among testosterone (T), aggression, and parental care have received much investigative attention. Within birds, many studies have focused on examining such relationships using species characterized by relatively brief periods of territoriality and breeding. Few have investigated links between circulating T and reproductive behavior in birds that are year-round territorial residents and have lengthy breeding seasons, such as the Northern Cardinal (Cardinalis cardinalis). The following six chapters report and discuss findings from this dissertation’s examination of aspects of T production and potential interconnections with circulating T, aggression, and parental care in male and female cardinals. This work suggests …
A Bird In The Binoculars: Understanding Birdwatchers' Potential To Contribute To Sustainable Development And Biological Conservation, Sheri Lynn Glowinski
A Bird In The Binoculars: Understanding Birdwatchers' Potential To Contribute To Sustainable Development And Biological Conservation, Sheri Lynn Glowinski
Dissertations
The three studies comprising this research drew from local economic development and environmental sociology to understand aspects of human dynamics that influence the conservation of birds. Using survey data collected from birdwatchers visiting coastal Alabama, the first study examined the local economic impact of birdwatching tourism and the factors that participants deemed important with respect to their recreation. Birdwatchers spent $103,305 during the four month study period. The total annual economic impact of this recreation on the area was estimated at $937,470, producing a multiplier of 1.48 and the equivalent of 20.3 full time jobs. Infrastructural variables (parking, bathrooms, site …
Sprague's Pipit In Clay County, Philip Chu
Sprague's Pipit In Clay County, Philip Chu
Biology Faculty Publications
No abstract provided.
Migration Timing And Wintering Areas Of Three Species Of Flycatchers (Tyrannus) Breeding In The Great Plains Of North America, Alex E. Jahn, Victor R. Cueto, James W. Fox, Michael S. Husak, Daniel H. Kim, Diane V. Landoll, Jesús Pinto Ledezma, Heather K. Lepage, Douglas J. Levey, Michael T. Murphy, Rosalind B. Renfrew
Migration Timing And Wintering Areas Of Three Species Of Flycatchers (Tyrannus) Breeding In The Great Plains Of North America, Alex E. Jahn, Victor R. Cueto, James W. Fox, Michael S. Husak, Daniel H. Kim, Diane V. Landoll, Jesús Pinto Ledezma, Heather K. Lepage, Douglas J. Levey, Michael T. Murphy, Rosalind B. Renfrew
Biology Faculty Publications and Presentations
Descriptions of intra- and interspecific variation in migratory patterns of closely related species are rare yet valuable because they can help assess how differences in ecology and life-history strategies drive the evolution of migration. We report data on timing and location of migration routes and wintering areas, and on migratory speed and phenology, of Eastern Kingbirds (Tyrannus tyrannus) from Nebraska and Oklahoma and of Western Kingbirds (T. verticalis) and Scissor-tailed Flycatchers (T. forficatus) from Oklahoma. Eastern Kingbirds primarily departed the breeding site in September, migrating to the Amazon Basin (Bolivia and Brazil), >6,400 km …
Melanin Concentration Gradients In Modern And Fossil Feathers, Daniel J. Field, Liliana D’Alba, Jakob Vinther, Samuel M. Webb, William Gearty, Matthew D. Shawkey
Melanin Concentration Gradients In Modern And Fossil Feathers, Daniel J. Field, Liliana D’Alba, Jakob Vinther, Samuel M. Webb, William Gearty, Matthew D. Shawkey
School of Biological Sciences: Faculty Publications
In birds and feathered non-avian dinosaurs, within-feather pigmentation patterns range from discrete spots and stripes to more subtle patterns, but the latter remain largely unstudied. A ,55 million year old fossil contour feather with a dark distal tip grading into a lighter base was recovered from the Fur Formation in Denmark. SEM and synchrotron-based trace metal mapping confirmed that this gradient was caused by differential concentration of melanin. To assess the potential ecological and phylogenetic prevalence of this pattern, we evaluated 321 modern samples from 18 orders within Aves. We observed that the pattern was found most frequently in distantly …
The Influence Of Different Cover Types On American Robin Nest Success In Organic Agroecosystems, John E. Quinn, Amy Oden, James R. Brandle
The Influence Of Different Cover Types On American Robin Nest Success In Organic Agroecosystems, John E. Quinn, Amy Oden, James R. Brandle
Biology Publications
There are many opportunities for biodiversity conservation in organic farm systems. Successful and sustainable conservation efforts in organic systems, however, need to measure appropriate outcomes. In particular, data are needed on the breeding success of associated wildlife species. We measured nesting success of the American Robin (Turdus migratorius) in woodlands embedded within eight organic farms in eastern Nebraska. We modeled daily nest survival rate to identify land use and land cover patterns that optimize conservation of birds in organic farm systems. The percentage of a crop in the fields adjacent to linear woodlands best predicted daily survival rate. …
The Effect Of Visual Wulst Lesions And Trigeminal Nerve Sectioning On The Discrimination Of Magnetic Inclination In The Homing Pigeon (Columba Livia), Merissa Acerbi
Honors Projects
The ability of homing pigeons to return to their loft from unknown places has fascinated scientists for centuries. It is well established that homing pigeons, like migratory birds, posses an innate magnetic inclination compass to determine direction by measuring the angle between the magnetic field vector and the Earth's surface. Recent work has indicated that the avian magnetic compass is light mediated and appears to mediate magnetic information to the brain. This occurs via a visual pathway with processing in the visual Wulst area of the forebrain. There is, however, also evidence from other avian species that magnetic direction may …
Influence Of Latitude On The Winter Abundance Of Red-Tailed Hawks (Buteo Jamaicensis) And American Kestrels (Falco Sparverius) In Illinois, Given Harper, Anna Groves, Vic Berardi, Paul Sweet, Jance Sweet, Angelo Capparella
Influence Of Latitude On The Winter Abundance Of Red-Tailed Hawks (Buteo Jamaicensis) And American Kestrels (Falco Sparverius) In Illinois, Given Harper, Anna Groves, Vic Berardi, Paul Sweet, Jance Sweet, Angelo Capparella
Scholarship
We use five years of data from 18 routes surveyed to determine the temporal stability of a first reported 100 years pattern, and reconfirmed that the abundance of winter 50 years ago tailed Hawk and American Kestrel decreases with increasing latitude, being more high in the central regions of Illinos in the northern regions. Trained volunteers conducted sampling ( n = 143) a month driving along selected routes from December to February, from 2004-2005 to 2008-2009. We found significant increases in the abundance of both species from the northern regions to the central regions of Illinois. No significant effects of …
Different Modes Of Evolution In Males And Females Generate Dichromatism In Fairy-Wrens (Maluridae), Allison E. Johnson, J. Jordan Price, Stephen Pruett-Jones
Different Modes Of Evolution In Males And Females Generate Dichromatism In Fairy-Wrens (Maluridae), Allison E. Johnson, J. Jordan Price, Stephen Pruett-Jones
School of Biological Sciences: Faculty Publications
Sexual dichromatism in birds is often attributed to selection for elaboration in males. However, evolutionary changes in either sex can result in plumage differences between them, and such changes can result in either gains or losses of dimorphism. We reconstructed the evolution of plumage colors in both males and females of species in Maluridae, a family comprising the fairy-wrens (Malurus, Clytomias, Sipodotus), emu-wrens (Stipiturus), and grasswrens (Amytornis). Our results show that, across species, males and females differ in their patterns of color evolution. Male plumage has diverged at relatively steady rates, whereas …
Cooperative Breeding And Long-Distance Dispersal: A Test Using Vagrant Records, Caroline L. Rusk, Eric L. Walters, Walter D. Koenig
Cooperative Breeding And Long-Distance Dispersal: A Test Using Vagrant Records, Caroline L. Rusk, Eric L. Walters, Walter D. Koenig
Biological Sciences Faculty Publications
Cooperative breeding is generally associated with increased philopatry and sedentariness, presumably because short-distance dispersal facilitates the maintenance of kin groups. There are, however, few data on long-distance dispersal in cooperative breeders-the variable likely to be important for genetic diversification and speciation. We tested the hypothesis that cooperative breeders are less likely to engage in long-distance dispersal events by comparing records of vagrants outside their normal geographic range for matched pairs (cooperatively vs. non-cooperatively breeding) of North American species of birds. Results failed to support the hypothesis of reduced long-distance dispersal among cooperative breeders. Thus, our results counter the conclusion that …
Factors Shaping The Ontogeny Of Vocal Signals In A Wild Parrot, Karl S. Berg, Steven R. Beissinger, Jack W. Bradbury
Factors Shaping The Ontogeny Of Vocal Signals In A Wild Parrot, Karl S. Berg, Steven R. Beissinger, Jack W. Bradbury
School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)
Parrots rely heavily on vocal signals to maintain their social and mobile lifestyles. We studied vocal ontogeny in nests of wild green-rumped parrotlets (Forpus passerinus) in Venezuela. We identified three successive phases of vocal signaling that corresponded closely to three independently derived phases of physiological development. For each ontogenetic phase, we characterized the relative importance of anatomical constraints, motor skills necessary for responding to specific contexts of the immediate environment, and the learning of signals that are necessary for adult forms of communication. We observed shifts in the relative importance of these three factors as individuals progressed from …
Breeding Biology Of Chuck-Will's-Widows: Incubation, Brooding, And Provisioning Behavior And Characteristics Of Nest Sites, Ryan Sean O'Connor
Breeding Biology Of Chuck-Will's-Widows: Incubation, Brooding, And Provisioning Behavior And Characteristics Of Nest Sites, Ryan Sean O'Connor
Online Theses and Dissertations
Chuck-will's-widows (Antrostomus carolinensis) are cryptically colored grounding-nesting nightars that breed throughout much of the eastern United States, primarily in mixed-forest habitat. Because of their cryptic plumage and nocturnal habits, little is known about their behavior, particularly their breeding and nesting behavior. Thus, my objectives were to: (1) quantify patterns of incubation behavior (e.g., on bouts vs. off bouts) and the respective roles of males and females, (2) quantify the brooding and provisioning behavior of males and females, and, (3) compare the characteristics of nest sites and randomly selected unused sites to determine those features important in nest site selection.
My …
Birds In Residential Metropolitan New Orleans Neighborhoods And Their Relationships To The Batture And Yard Vegetation, Ruth A. Guymon
Birds In Residential Metropolitan New Orleans Neighborhoods And Their Relationships To The Batture And Yard Vegetation, Ruth A. Guymon
LSU New Orleans Theses and Dissertations
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 …
The Breeding Biology Of The Northern Pygmy Owl: Do The Smallest Of The Small Have An Advantage?, John F. Deshler, Michael T. Murphy
The Breeding Biology Of The Northern Pygmy Owl: Do The Smallest Of The Small Have An Advantage?, John F. Deshler, Michael T. Murphy
Biology Faculty Publications and Presentations
We explored the breeding biology of the Northern Pygmy-Owl (Glaucidium gnoma) from 2007 to 2009 in a forested reserve in Portland, Oregon. Large body size is often assumed to give animals reproductive advantages, and we tested whether body size affected timing of breeding and examined variation in diet, breeding date, clutch size, and reproductive success to explore whether the presumed benefits of large body size are evident in this species. The average size of 13 clutches was 5.8, and nest success was high (92%); 22 successful nests fledged an average of 5.2 young. Dates of first laying varied …
Nutritional Content Of Rhinoceros Auklet (Cerorhinca Monocerata) Bill Loads, Dustin Taylor, Ron Heintz
Nutritional Content Of Rhinoceros Auklet (Cerorhinca Monocerata) Bill Loads, Dustin Taylor, Ron Heintz
STAR Program Research Presentations
Nutritional Content of Rhinoceros Auklet Bill Loads
Dustin E Taylor
Abstract
An adult Rhinoceros Auklet (Cerorhinca monocerata) can only catch and carry a limited amount of prey to their nestlings after a foraging trip. The auklets therefore must maximize their efficiency by bringing back the most proportionally nutritious prey items to their nestlings. The prey carried back to the nesting sites (known as a ‘bill load’) can contain whole fish, as well as parts, most commonly fish heads. This study is aimed to determine whether returning with just heads to the nestlings was proportionally more nutritious than bringing …
Potential For Barn Owl As Rodent Biological Control In Central California Vineyards, Hannah Tillmann
Potential For Barn Owl As Rodent Biological Control In Central California Vineyards, Hannah Tillmann
Biological Sciences
The pocket gopher (Thomomys bottae) and voles (Microtus spp.) cause significant economic damage to vineyards. In response, many growers have taken steps to attract Barn Owls (Tyto alba) to their properties to help keep these rodent populations in check. This research project investigated Barn Owl consumption of pocket gophers and voles in Central California vineyards in order to assess the efficiency of this integrated pest management strategy. I collected a total of 715 owl pellets from five vineyard locations in Templeton and Paso Robles, California over an eight-month period during nesting and post-fledging seasons. I …
Brooding, Provisioning, And Compensatory Care In The Cooperatively Breeding Acorn Woodpecker, Walter D. Koenig, Eric L. Walters
Brooding, Provisioning, And Compensatory Care In The Cooperatively Breeding Acorn Woodpecker, Walter D. Koenig, Eric L. Walters
Biological Sciences Faculty Publications
We analyzed reproductive investment in parental care (brooding and the provisioning of nestlings) in the acorn woodpecker (Melanerpes formicivorus), a cooperatively breeding species in which both polygynandry and helping-at-the-nest are common. As predicted based on the strategies pursued by birds of different sex and status, breeders generally invested more in parental care than helpers, and breeder females invested more than breeder males. Contrary to expectations, however, the degree to which individuals reduced their effort with increasing group size (i.e., patterns of load lightening or compensatory care) did not match overall investment. Instead, as group size increased, there was …
Tick Infestations And Their Consequences For Migratory Songbirds During Spring Stopover, Johnny Michael Sellers Jr.
Tick Infestations And Their Consequences For Migratory Songbirds During Spring Stopover, Johnny Michael Sellers Jr.
Master's Theses
Migratory birds face a number of challenges during their seasonal movement from tropical/sub-tropical Central and South America to more temperate North America. Maintaining health during migration is of particular concern. This study seeks to understand how haematophageous ectoparasites, such as ticks (Ixodida), impact host body condition as they feed on passerines during migration. We hypothesized that foraging location would impact tick acquisition by migrants and that tick burdens during migration would negatively impact body condition. We surveyed 2,064 birds during spring 2009 and 2010 and found that 2.4% of the surveyed birds were infested with one or more …