Open Access. Powered by Scholars. Published by Universities.®

Ecology and Evolutionary Biology Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 6 of 6

Full-Text Articles in Ecology and Evolutionary Biology

An Agent-Based Modeling Approach To Determine Winter Survival Rates Of American Robins And Eastern Bluebirds, Samuel Iselin, Shannon Segin, Alex Capaldi Dec 2015

An Agent-Based Modeling Approach To Determine Winter Survival Rates Of American Robins And Eastern Bluebirds, Samuel Iselin, Shannon Segin, Alex Capaldi

Alex Capaldi

American Robins (Turdus migratorius) and Eastern Bluebirds (Sialia sialis) are two species of migratory thrushes that breed in Northwest Indiana but historically are uncommon during the winter season. These trends have changed recently, and both species are seen more abundantly during the winter. Recently invaded non-native fruiting plants continue to provide nutrients for the birds throughout the winter and may contribute to the increased avian populations during that time. To measure the effect these food sources contribute to thrush wintering habits, we created an agent-based computer model to simulate the birds' movement in Northwest Indiana along …


Genetic Approaches To The Conservation Of Migratory Bats: A Study Of The Eastern Red Bat (Lasiurus Borealis), Maarten J. Vonhof, Amy L. Russell Apr 2015

Genetic Approaches To The Conservation Of Migratory Bats: A Study Of The Eastern Red Bat (Lasiurus Borealis), Maarten J. Vonhof, Amy L. Russell

Amy L. Russell

Documented fatalities of bats at wind turbines have raised serious concerns about the future impacts of increased wind power development on populations of migratory bat species. However, for most bat species we have no knowledge of the size of populations and their demographic trends, the degree of structuring into discrete subpopulations, and whether different subpopulations use spatially segregated migratory routes. Here, we utilize genetic data from eastern red bats (Lasiurus borealis), one of the species most highly affected by wind power development in North America, to (1) evaluate patterns of population structure across the landscape, (2) estimate effective population size …


Wintering Ecology Of Adult North American Ospreys, Brian E. Washburn, Charles J. Henny, Mark S. Martell, Richard O. Bierregaard, Brian S. Dorr, Thomas J. Olexa Dec 2014

Wintering Ecology Of Adult North American Ospreys, Brian E. Washburn, Charles J. Henny, Mark S. Martell, Richard O. Bierregaard, Brian S. Dorr, Thomas J. Olexa

Brian S Dorr

North American Ospreys (Pandion haliaetus) typically migrate long distances to their wintering grounds in the tropics. Beyond the general distribution of their wintering range (i.e., the Caribbean, South America, and Central America), very little is known about the wintering ecology of these birds. We used satellite telemetry to determine the duration of wintering period, to examine the characteristics of wintering areas used by Ospreys, and to quantify space use and activity patterns of wintering Ospreys. Adult Ospreys migrated to wintering sites and exhibited high wintering site fidelity among years. Overall, Ospreys wintered on river systems (50.6%) more than on lakes …


Determinants Of Local And Migratory Movements Of Great Lakes Double-Crested Cormorants, Alban Guillaumet, Brian S. Dorr, Guiming Wang, Jimmy D. Taylor Ii, Richard B. Chipman, Heidi Scherr, Jeff Bowman, Kenneth F. Abraham, Terry J. Doyle, Elizabeth Cranker Jun 2011

Determinants Of Local And Migratory Movements Of Great Lakes Double-Crested Cormorants, Alban Guillaumet, Brian S. Dorr, Guiming Wang, Jimmy D. Taylor Ii, Richard B. Chipman, Heidi Scherr, Jeff Bowman, Kenneth F. Abraham, Terry J. Doyle, Elizabeth Cranker

Brian S Dorr

We investigated how individual strategies combine with demographic and ecological factors to determine local and migratory movements in the double-crested cormorants (Phalacrocorax auritus). One hundred and forty-five cormorants were captured from 14 nesting colonies across the Great Lakes area and fitted with satellite transmitters. We first tested the hypotheses that sexual segregation, density-dependent effects, and the intensity of management operations influenced home range size during the breeding season. The influence of these factors appeared to be limited in part due to random variability in foraging and dispersal decisions at individual and colony levels. We also designed a statistical framework to …


Evaluation Of Harassment Of Migrating Double-Crested Cormorants To Limit Depredation On Selected Sport Fisheries In Michigan, Brian S. Dorr, Ashley Moerke, Michael Bur, Chuck Bassett, Tony Aderman, Dan Traynor, Russell D. Singleton, Peter H. Butchko, Jimmy D. Taylor Nov 2010

Evaluation Of Harassment Of Migrating Double-Crested Cormorants To Limit Depredation On Selected Sport Fisheries In Michigan, Brian S. Dorr, Ashley Moerke, Michael Bur, Chuck Bassett, Tony Aderman, Dan Traynor, Russell D. Singleton, Peter H. Butchko, Jimmy D. Taylor

Brian S Dorr

No abstract provided.


Genetic Variation And Migration In The Mexican Free-Tailed Bat (Tadarida Brasiliensis Mexicana), Amy L. Russell, R. A. Medellín, G. F. Mccracken Dec 2004

Genetic Variation And Migration In The Mexican Free-Tailed Bat (Tadarida Brasiliensis Mexicana), Amy L. Russell, R. A. Medellín, G. F. Mccracken

Amy L. Russell

Incomplete lineage sorting can genetically link populations long after they have diverged, and will exert a more powerful influence on larger populations. The effects of this stochastic process can easily be confounded with those of gene flow, potentially leading to inaccurate estimates of dispersal capabilities or erroneous designation of evolutionarily significant units (ESUs). We have used phylogenetic, population genetic, and coalescent methods to examine genetic structuring in large populations of a widely dispersing bat species and to test hypotheses concerning the influences of coalescent stochasticity vs. gene flow. The Mexican free-tailed bat, Tadarida brasiliensis mexicana, exhibits variation in both migra- …