Life Sciences Commons^™

A Multi-Isotope Approach Reveals Seasonal Variation In The Reliance On Marine Resources, Production Of Metabolic Water, And Ingestion Of Seawater By Two Species Of Coastal Passerine To Maintain Water Balance, Lucas Navarrete, Nico Lübcker, Felipe Alvarez, Roberto Nespolo, Juan Carlos Sanchez-Hernandez, Karin Maldonado, Zachary D. Sharp, John P. Whiteman, Seth D. Newsome, Pablo Sabat

Biological Sciences Faculty Publications

Tracing how free-ranging organisms interact with their environment to maintain water balance is a difficult topic to study for logistical and methodological reasons. We use a novel combination of triple-oxygen stable isotope analyses of water extracted from plasma (δ¹⁶O, δ¹⁷O, δ¹⁸O) and bulk tissue carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopes of feathers and blood to estimate the proportional contribution of marine resources, seawater, and metabolic water used by two species of unique songbirds (genus Cinclodes) to maintain their water balance in a seasonal coastal environment. We …

Lifetime Inclusive Fitness Effects Of Cooperative Polygamy In The Acorn Woodpecker, Walter D. Koenig, Sahas Barve, Joseph Haydock, Eric L. Walters

Biological Sciences Faculty Publications

Although over 50 y have passed since W. D. Hamilton articulated kin selection and inclusive fitness as evolutionary explanations for altruistic behavior, quantifying inclusive fitness continues to be challenging. Here, using 30 y of data and two alternative methods, we outline an approach to measure lifetime inclusive fitness effects of cooperative polygamy (mate-sharing or cobreeding) in the cooperatively breeding acorn woodpecker Melanerpes formicivorus. For both sexes, the number of offspring (observed direct fitness) declined while the number of young parented by related cobreeders (observed indirect fitness effect) increased with cobreeding coalition size. Combining these two factors, the observed inclusive …

Breeding Birds Of Virginia, Bryan D. Watts

Virginia Journal of Science

Virginia supports a diverse community of breeding birds that has been the focus of investigation for more than 400 years. The avifauna reflects the latitudinal position of the state and the fact that the border extends from the Atlantic Ocean to the Appalachian Mountains. A total of 224 species have been recorded breeding in Virginia, 214 of which are extant. Twenty species have colonized the state since 1900 including 14 since 1950. Of all extant species, 102 (48%) are considered common at least somewhere in the state and 64 (30%) are rare to very rare. Diversity varies by physiographic region …

The Effects Of Urbanization On Tick Parasitism Rates In Birds Of Southeastern Virginia, Erin Leigh Heller

Biological Sciences Theses & Dissertations

The coastal region of southeastern Virginia is one of the largest urban areas along one of North America’s migratory flyways. Because hundreds of avian species use this flyway, understanding factors affecting birds and their health is of paramount concern. Within this region, 14 species of ticks have been documented, all of which may serve as vectors of mammal (including human) pathogens. By sampling birds at sites of varying levels of urbanization within the coastal southeastern urban matrix, I studied the relationship between ticks and their avian hosts, and how this relationship varies seasonally. Mistnets were set-up at five permanent sites …

A Comparison Of Techniques Measuring Stress In Birds, Deborah A. O'Dell, Michael A. Carlo, Abigail Kimmitt, Ellen Bikowski, Katherine R. Morris, Andrew Dolby

Virginia Journal of Science

Free-living birds are subjected to both external and internal stresses which can affect their health, activity, and reproductive success. To study stress in free living birds, they must be captured in nets and handled by the researcher to take blood samples for commonly used measures of stress, an activity which itself can induce stress and confound results. This study compares the effects of handling time on three different measures of stress: levels of the stress hormone corticosterone (CORT), levels of Heat Shock Protein 60 (HSP 60) and the ratio of heterophils to lymphocytes (H/L ratio) in tufted titmouse (Baeolophus bicolor …

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 …

Brown-Headed Cowbird (Molothrus Ater) Range Expansion Into The Southeast: Effects On The Passerine Populations Using North American Breeding Bird Survey Data, Elizabeth Pruitt Henderson

Biological Sciences Theses & Dissertations

North American Breeding Bird Survey data that were collected from 1971-1992 in Virginia, North Carolina, south Carolina, Georgia, Florida, Alabama and Tennessee were used in this analysis of the impact of Brown-headed Cowbird range expansion on four warbler and four vireo host species.

Maps of mean cowbird abundances were produced using kriging for the periods 1971-1975, 1976-1980, 1981-1985, 1986-1990 and 1991-1992. These maps illustrated a complex invasion of the southeastern United States by Brown-headed Cowbird.

Linear regression analyses of host and cowbird abundances within physiographic strata, showed no species to be in decline or increasing in abundance over the entire …

Determinants Of Variation In Avian Mobbing Behavior, Charles Ray Chandler Jr.

Biological Sciences Theses & Dissertations

Using three combinations of two experimental stimuli, I initiated mobbing behavior in various species of birds. The objectives of this research were to test the effects of stimuli on mobbing, the predictions of the hypothesis that mobbing functions to drive a predator away, and the effect of other species and individuals on the mobbing behavior of a bird. Mobbing experiments were conducted in a variety of habitats and locations from January 1983 through February 1984.

Only 6.5% of all trials with the mount-only stimulus were successful in attracting birds. Tape-only and mount-and-tape stimuli were equally effective in attracting birds, but …

Breeding Birds In Cedar Stands In The Great Dismal Swamp, Karen A. Terwilliger, Robert K. Rose

Biological Sciences Faculty Publications

The Great Dismal Swamp located in the coastal plain on the Virginia- North Carolina border, has long been recognized as a vegetationally distinctive region with many unusual geological and biological features. Formerly at least twice the currently estimated size of 85,000 hectares (Carter 1979), the Great Dismal Swamp is still shrinking because of a dropping water table caused by more than 200 years of logging, ditching, and other human activities. In 1973, the Union Camp Corporation donated a 19,871-hectare tract located near Suffolk, Virginia. to The Nature Conservancy, which transferred the land to the U.S. Fish and Wildlife Service. This …