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Social and Behavioral Sciences Commons

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

2003

International and Area Studies

Bobolink

Articles 1 - 2 of 2

Full-Text Articles in Social and Behavioral Sciences

Guidelines For Finding Nests Of Passerine Birds In Tallgrass Prairie, Maiken Winter, Shawn E. Hawks, Jill A. Shaffer, Douglas H. Johnson Jul 2003

Guidelines For Finding Nests Of Passerine Birds In Tallgrass Prairie, Maiken Winter, Shawn E. Hawks, Jill A. Shaffer, Douglas H. Johnson

USGS Northern Prairie Wildlife Research Center

The productivity of birds is one of the most critical components of their natural history affected by habitat quality. Birds might occur at high densities in a given habitat patch but have low nesting success. Such "population sinks" would not be detected if observers relied solely on estimates of bird density. Therefore, it is essential to monitor nests and determine their outcomes. Although interest in grassland-nesting passerines has increased greatly during the last decade, we still know little about factors affecting their nesting success. To stimulate more research in this area, we summarize several methods for nest-searching and provide suggestions …


Effects Of Leafy Spurge Infestation On Grassland Birds, Daniel M. Scheiman, Eric K. Bollinger, Douglas H. Johnson Jan 2003

Effects Of Leafy Spurge Infestation On Grassland Birds, Daniel M. Scheiman, Eric K. Bollinger, Douglas H. Johnson

USGS Northern Prairie Wildlife Research Center

Grassland bird populations are declining. Invasive plant species may be contributing to these declines by altering habitat quality. However, the effects of invasive plants on grassland birds are largely unknown. Leafy spurge (Euphorbia esula) is an exotic, invasive weed in the northern Great Plains. We examined the effects of leafy spurge infestation on densities of breeding birds, nest-site selection, and nest success in grasslands on the Sheyenne National Grassland (SNG), North Dakota, USA, 1999-2000. We categorized spurge-infested grasslands into 3 groups (low, medium, high), based on the area covered by spurge patches. We surveyed 75 100-m-radius circular points …