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- Rotationally grazed pasture (2)
- Vermont (2)
- Antipredator (1)
- Apparent survival (1)
- Champlain Valley New York and Vermont (1)
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- Fisher’s hypothesis (1)
- Fledglings (1)
- Fragmentation (1)
- Grassland hayfield management (1)
- Grassland management (1)
- Habitat selection (1)
- Hayfield (1)
- Homeostasis hypothesis (1)
- Local dispersal (1)
- Logistic exposure (1)
- Nest success (1)
- Nestling sex ratio adjustment (1)
- New York (1)
- Openness (1)
- Realized lambda (1)
- Recruitment (1)
- Reproductive success (1)
Articles 1 - 4 of 4
Full-Text Articles in Environmental Health and Protection
Nestling Sex Ratios Do Not Support Long-Term Parity In Two Species With Different Life-History Strategies, Noah G. Perlut, Steven E. Travis, Catherine A. Dunbar, Allan M. Strong, Derek M. Wright
Nestling Sex Ratios Do Not Support Long-Term Parity In Two Species With Different Life-History Strategies, Noah G. Perlut, Steven E. Travis, Catherine A. Dunbar, Allan M. Strong, Derek M. Wright
Environmental Studies Faculty Publications
To maximize fitness, breeding adults may respond to environmental processes by adjusting their progeny’s sex ratios. R. A. Fisher in 1930 hypothesized that frequency-dependent selection would result in equal investment in sons and daughters over the long term, yielding a balanced sex ratio if the costs of raising a son and daughter are equal. Diverse hypotheses have tried to explain population and brood-by-brood deviations from this mean as well as annual variation by focusing on adult sex ratios, resources, abiotic conditions, and female and male quality. We collected data in 2002-2010 to explore population-level variation in nestling sex ratios in …
Evaluating The Roles Of Visual Openness And Edge Effects On Nest-Site Selection And Reproductive Success In Grassland Birds, Alexander C. Keyel, Allan M. Strong, Noah G. Perlut, J. Michael Reed
Evaluating The Roles Of Visual Openness And Edge Effects On Nest-Site Selection And Reproductive Success In Grassland Birds, Alexander C. Keyel, Allan M. Strong, Noah G. Perlut, J. Michael Reed
Environmental Studies Faculty Publications
In some species, habitat edges (ecotones) affect nest-site selection and nesting success. Openness, or how visually open a habitat is, has recently been shown to influence grassland bird density and may affect nest-site selection, possibly by reducing the risk of predation on adults, nests, or both. Because edge and openness are correlated, it is possible that effects of openness have been overlooked or inappropriately ascribed to edge effects. We tested the roles of edges and visual openness in nest-site selection and nesting success of two grassland passerines, the Bobolink (Dolichonyx oryzivorus) and Savannah Sparrow (Passerculus sandwichensis), …
Grassland Songbird Survival And Recruitment In Agricultural Landscapes: Implications For Source-Sink Demography, Noah G. Perlut, Allan M. Strong, Therese M. Donovan, Neil J. Buckley
Grassland Songbird Survival And Recruitment In Agricultural Landscapes: Implications For Source-Sink Demography, Noah G. Perlut, Allan M. Strong, Therese M. Donovan, Neil J. Buckley
Environmental Studies Faculty Publications
Population growth and decline are particularly sensitive to changes in three key life-history parameters: annual productivity, juvenile survival, and adult survival. However, for many species these parameters remain unknown. For example, although grassland songbirds are imperiled throughout North America, for this guild, only a small number of studies have assessed these parameters. From 2002 to 2006, in the agricultural landscape of the Champlain Valley of Vermont and New York, USA, we studied Savannah Sparrow (Passerculus sandwichensis) and Bobolink (Dolichonyx oryzivorus) demography on four grassland treatments: (1) early-hayed fields cut before 11 June and again in early- …
Grassland Songbirds In A Dynamic Management Landscape: Behavioral Responses And Management Strategies, Noah G. Perlut, Allan M. Strong, Therese M. Donovan, Neil J. Buckley
Grassland Songbirds In A Dynamic Management Landscape: Behavioral Responses And Management Strategies, Noah G. Perlut, Allan M. Strong, Therese M. Donovan, Neil J. Buckley
Environmental Studies Faculty Publications
In recent decades, earlier and more frequent harvests of agricultural grasslands have been implicated as a major cause of population declines in grassland songbirds. From 2002 to 2005, in the Champlain Valley of Vermont and New York, USA, we studied the reproductive success of Savannah Sparrows (Passerculus sandwichensis) and Bobolinks (Dolichonyx oryzivorus) on four grassland treatments: (1) early-hayed fields cut before 11 June and again in early- to mid-July; (2) middle-hayed fields cut once between 21 June and 10 July; (3) late-hayed fields cut after 1 August; and (4) rotationally grazed pastures. Both the number of …