Ornithology Commons^™

Modeling Habitat Associations For The Common Loon (Gavia Immer) At Multiple Scales In Northeastern North America, Anne Kuhn, Jane Copeland, John Cooley, Harry Vogel, Kate Taylor, Diane Nacci, Peter V. August

Peter August

Common Loon (Gavia immer) is considered an emblematic and ecologically important example of aquatic-dependent wildlife in North America. The northern breeding range of Common Loon has contracted over the last century as a result of habitat degradation from human disturbance and lakeshore development. We focused on the state of New Hampshire, USA, where a long-term monitoring program conducted by the Loon Preservation Committee has been collecting biological data on Common Loon since 1976. The Common Loon population in New Hampshire is distributed throughout the state across a wide range of lake-specific habitats, water quality conditions, and levels of human disturbance. …

House Finch Populations Differ In Early Inflammatory Signaling And Pathogen Tolerance At The Peak Of Mycoplasma Gallisepticum Infection, James S. Adelman, Laila Kirkpatrick, Jessica L. Grodio, Dana M. Hawley

James S. Adelman

Host individuals and populations often vary in their responses to infection, with direct consequences for pathogen spread and evolution. While considerable work has focused on the mechanisms underlying differences in resistance—the ability to kill pathogens— we know little about the mechanisms underlying tolerance— the ability to minimize fitness losses per unit pathogen. Here, we examine patterns and mechanisms of tolerance between two populations of house finches (Haemorhous [formerly Carpodacus] mexicanus) with different histories with the bacterial pathogen Mycoplasma gallisepticum (MG). After infection in a common environment, we assessed two metrics of pathology, mass loss and eye lesion severity, as proxies …

Predicting Nesting Habitat Of Northern Goshawks In Mixed Aspen-Lodgepole Pine Forests In A High-Elevation Shrub-Steppe Dominated Landscape., Robert A. Miller, Jay D. Carlisle, Marc J. Bechard, Dena Santini

Robert Miller

We developed a habitat suitability model for predicting nest locations of breeding Northern Goshawks (Accipiter gentilis) in the high-elevation mixed forest and shrub-steppe habitat of south-central Idaho, USA. We used elevation, slope, aspect, ruggedness, distance-to-water, canopy cover, and individual bands of Landsat imagery as predictors for known nest locations with logistic regression. We found goshawks prefer to nest in gently-sloping, east-facing, non-rugged areas of dense aspen and lodgepole pine forests with low reflectance in green (0.53 - 0.61 μm) wavelengths during the breeding season. We used the model results to classify our 43,169 hectare study area into nesting suitability categories: …

Modeling Parasitism Rate And Parasitism Risk: An Illustration Using A Colonially Nesting Songbird, The Red-Winged Blackbird Agelaius Phoeniceus, Max Post Van Der Burg, Larkin A. Powell, Andrew J. Tyre

Andrew J Tyre

Ornithologists interested in the drivers of nest success and brood parasitism benefit from the development of new analytical approaches. One example is the development of so-called “log exposure” models for analyzing nest success. However, analyses of brood parasitism data have not kept pace with developments in nest success analyses. The standard approach uses logistic regression which does not account for multiple parasitism events, nor does it prevent bias from using observed proportions of parasitized nests. Likewise, logistic regression analyses do not capture fine scale temporal variation in parasitism. At first glance, it might be tempting to apply log exposure models …

A Study Of Mexican Free-Tailed Bat Chirp Syllables: Bayesian Functional Mixed Modeling Of Nonstationary Time Series Data With Time-Dependent Spectra, Josue G. Martinez, Kirsten M. Bohn, Raymond J. Carroll, Jeffrey S. Morris

Jeffrey S. Morris

We describe a new approach to analyze chirp syllables of free-tailed bats from two regions of Texas in which they are predominant: Austin and College Station. Our goal is to characterize any systematic regional differences in the mating chirps and assess whether individual bats have signature chirps. The data are analyzed by modeling spectrograms of the chirps as responses in a Bayesian functional mixed model. Given the variable chirp lengths, we compute the spectrograms on a relative time scale interpretable as the relative chirp position, using a variable window overlap based on chirp length. We use 2D wavelet transforms to …

Species Diversity And Abundance Of Avifauna In And Around Hombolo Wetland In Central Tanzania, Geofrey Soka, Pkt Munishi, Bernad Mgina

Geofrey Soka

No abstract provided.

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 P. Capparella

Given Harper

Melanistic Adult Male Northern Harrier Wintering In Idaho, Robert A. Miller, Neil Paprocki, Elizabeth H. Urban

Robert Miller

Field observation of a Northern Harrier with rare aberrant plumage.