Open Access. Powered by Scholars. Published by Universities.®
- Institution
- Keyword
-
- Glaucous-winged Gull (2)
- Larus glaucescens (2)
- Bald Eagle (1)
- Conservation reserve program (1)
- Diet (1)
-
- Egg laying (1)
- Foraging (1)
- GnRH challenge (1)
- Grassland birds (1)
- Haliaeetus leucocephalus (1)
- Harbor seals (1)
- Landscape relations (1)
- Life-history trade-offs (1)
- Luteinizing hormone (1)
- Mathematical model (1)
- Natural selection (1)
- Ovulation (1)
- Protection Island (1)
- Set-aside (1)
- Sexual selection (1)
- Synchrony (1)
- Testosterone (1)
- Washington (1)
Articles 1 - 5 of 5
Full-Text Articles in Animal Sciences
Integrating Concepts And Technologies To Advance The Study Of Bird Migration, W. Douglas Robinson, Melissa Bowlin, Isabelle Bisson, Judy Shamoun-Barnes, Kasper Thorup, Robert H. Diehl, Thomas H. Kunz, Sarah Mabey, David W. Winkler
Integrating Concepts And Technologies To Advance The Study Of Bird Migration, W. Douglas Robinson, Melissa Bowlin, Isabelle Bisson, Judy Shamoun-Barnes, Kasper Thorup, Robert H. Diehl, Thomas H. Kunz, Sarah Mabey, David W. Winkler
Faculty Publications
Recent technological innovation has opened new avenues in migration research - for instance, by allowing individual migratory animals to be followed over great distances and long periods of time, as well as by recording physiological information. Here, we focus on how technology - specifically applied to bird migration - has advanced our knowledge of migratory connectivity, and the behavior, demography, ecology, and physiology of migrants. Anticipating the invention of new and smaller tracking devices, in addition to the ways that technologies may be combined to measure and record the behavior of migratory animals, we also summarize major conceptual questions that …
Natural Selection On Testosterone Production In A Wild Songbird Population, Joel W. Mcglothlin, Danielle J. Whittaker, Sara E. Schrock, Nicole M. Gerlach, Jodie M. Jawor, Eric A. Snajdr, Ellen D. Ketterson
Natural Selection On Testosterone Production In A Wild Songbird Population, Joel W. Mcglothlin, Danielle J. Whittaker, Sara E. Schrock, Nicole M. Gerlach, Jodie M. Jawor, Eric A. Snajdr, Ellen D. Ketterson
Faculty Publications
Because of their role in mediating life-history trade-offs, hormones are expected to be strongly associated with components of fitness; however, few studies have examined how natural selection acts on hormonal variation in the wild. In a songbird, the dark-eyed junco (Junco hyemalis), field experiments have shown that exogenous testosterone alters individuals' resolution of the survival-reproduction trade-off, enhancing reproduction at the expense of survival. Here we used standardized injections of gonadotropin-releasing hormone (GnRH) to assay variation in the testosterone production of males. Using measurements of annual survival and reproduction, we found evidence of strong natural selection acting on GnRH-induced …
Foraging-Related Activity Of Bald Eagles At A Washington Seabird Colony And Seal Rookery, James L. Hayward, Joseph G. Galusha, Shandelle M. Henson
Foraging-Related Activity Of Bald Eagles At A Washington Seabird Colony And Seal Rookery, James L. Hayward, Joseph G. Galusha, Shandelle M. Henson
Faculty Publications
From 1980 to 1998, Washington's Bald Eagle (Haliaeetus leucocephalus) population increased at an annual rate of 10. Over the same time period, foraging activity of Bald Eagles at marine bird breeding colonies also increased. From 1993 to 2008, we observed foraging-related behavior of Bald Eagles on Violet Point, Protection Island. This island hosts more than 70 of the breeding seabirds in Washington's inner seaways and serves as an important rookery for harbor seals (Phoca vitulina). We found that (1) eagles landed more frequently in seal haul-out (beach) areas than in gull-nesting (non-beach) areas of Violet Point, and that subadult eagles …
Broad-Scale Relations Between Conservation Reserve Program And Grassland Birds: Do Cover Type, Configuration And Contract Age Matter?, Sam Riffell, Daniel Scognamillo, L. Wes Burger Jr., Shawn Bucholtz
Broad-Scale Relations Between Conservation Reserve Program And Grassland Birds: Do Cover Type, Configuration And Contract Age Matter?, Sam Riffell, Daniel Scognamillo, L. Wes Burger Jr., Shawn Bucholtz
Faculty Publications
The Conservation Reserve Program (CRP) is a voluntary cropland set-aside program where environmentally-sensitive cropland is retired to a conservation practice. Grassland birds should benefit because most CRP is grass habitat and because amount of land in CRP is highest in agriculture-dominated areas of the United States where grassland habitat has been most impacted. We used the Breeding Bird Survey and Common Land Unit (CLU) data (spatially-explicit data of farm field boundaries and land cover) to identify relations between types and configurations of CRP and grassland bird abundance in 3 Midwestern states. All 13 species we studied were related to at …
Socially Induced Synchronization Of Every-Other-Day Egg Laying In A Seabird Colony, Shandelle M. Henson, James L. Hayward, J. M. Cushing, Joseph C. Galusha
Socially Induced Synchronization Of Every-Other-Day Egg Laying In A Seabird Colony, Shandelle M. Henson, James L. Hayward, J. M. Cushing, Joseph C. Galusha
Faculty Publications
Spontaneous oscillator synchrony has been documented in a wide variety of electrical, mechanical, chemical, and biological systems, including the menstrual cycles of women and estrous cycles of Norway Rats (Rattus norvegicus). In temperate regions, many colonial birds breed seasonally in a time window set by photoperiod; some studies have suggested that heightened social stimulation in denser colonies can lead to a tightened annual reproductive pulse. It has been unknown, however, whether the analog of menstrual synchrony occurs in birdsthat is, whether avian ovulation cycles can synchronize on a daily timescale within the annual breeding pulse. We report every-other-day clutch-initiation and …