Colleen Handel, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 90
Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific
The annual 29 000 km long migration of the bar-tailed godwit, Limosa lapponica baueri, around the Pacific Ocean traverses what is arguably the most complex and seasonally structured atmospheric setting on Earth. Faced with marked variation in wind regimes and storm conditions across oceanic migration corridors, individuals must make critical decisions about when and where to fly during nonstop fli
Authors
Robert E. Gill, David C. Douglas, Colleen M. Handel, T. Lee Tibbitts, Gary Hufford, Theunis Piersma
Reviving common standards in point-count surveys for broad inference across studies
We revisit the common standards recommended by Ralph et al. (1993, 1995a) for conducting point-count surveys to assess the relative abundance of landbirds breeding in North America. The standards originated from discussions among ornithologists in 1991 and were developed so that point-count survey data could be broadly compared and jointly analyzed by national data centers with the goals of monito
Authors
Steven M. Matsuoka, C. Lisa Mahon, Colleen M. Handel, Peter Solymos, Erin M. Bayne, Patricia C. Fontaine, C.J. Ralph
Wildlife health in a rapidly changing North: focus on avian disease
Climate-related environmental changes have increasingly been linked to emerging infectious diseases in wildlife. The Arctic is facing a major ecological transition that is expected to substantially affect animal and human health. Changes in phenology or environmental conditions that result from climate warming may promote novel species assemblages as host and pathogen ranges expand to previously u
Authors
Caroline R. Van Hemert, John M. Pearce, Colleen M. Handel
Coping with the cold: An ecological context for the abundance and distribution of rock sandpipers during winter in upper Cook Inlet, Alaska
Shorebirds are conspicuous and abundant at high northern latitudes during spring and summer, but as seasonal conditions deteriorate, few remain during winter. To the best of our knowledge, Cook Inlet, Alaska (60.6˚ N, 151.6˚ W), is the world’s coldest site that regularly supports wintering populations of shorebirds, and it is also the most northerly nonbreeding location for shorebirds in the Pacif
Authors
Daniel R. Ruthrauff, Robert E. Gill, T. Lee Tibbitts
Ecological correlates of variable organ sizes and fat loads in the most northerly-wintering shorebirds
Shorebirds at northern latitudes during the nonbreeding season typically carry relatively large lipid stores and exhibit an up-regulation of lean tissues associated with digestion and thermogenesis. Intraspecific variation in these tissues across sites primarily reflects differences in environmental conditions. Rock (Calidris ptilocnemis (Coues, 1873)) and Purple (Calidris maritima (Brünnich, 1764
Authors
Daniel R. Ruthrauff, Anne Dekinga, Robert E. Gill, R.W. Summers, Theunis Piersma
Intercontinental migratory connectivity and population structuring of Dunlins from western Alaska
The Dunlin (Calidris alpina) is a polytypic shorebird with complex patterns of distribution and migration throughout its holarctic range. We analyzed mark-re sighting data obtained between 1977 and 2010 from birds captured at two major staging areas in western Alaska to test the hypothesis that the migration patterns of Alaskan populations are a mixture of parallel and chain, similar to those of D
Authors
Robert E. Gill, Colleen M. Handel, Daniel R. Ruthrauff
Changing Arctic ecosystems--the role of ecosystem changes across the Boreal-Arctic transition zone on the distribution and abundance of wildlife populations
Arctic and boreal ecosystems provide important breeding habitat for more than half of North America’s migratory birds as well as many resident species. Northern landscapes are projected to experience more pronounced climate-related changes in habitat than most other regions. These changes include increases in shrub growth, conversion of tundra to forest, alteration of wetlands, shifts in species’
Authors
Lance McNew, Colleen M. Handel, John M. Pearce, Anthony R. DeGange, Leslie Holland-Bartels, Mary E. Whalen
Identical metabolic rate and thermal conductance in Rock Sandpiper (Calidris ptilocnemis) subspecies with contrasting nonbreeding life histories
Closely related species or subspecies can exhibit metabolic differences that reflect site-specific environmental conditions. Whether such differences represent fixed traits or flexible adjustments to local conditions, however, is difficult to predict across taxa. The nominate race of Rock Sandpiper (Calidris ptilocnemis) exhibits the most northerly nonbreeding distribution of any shorebird in the
Authors
Daniel R. Ruthrauff, Anne Dekinga, Robert E. Gill, Theunis Piersma
Macroscopic, histologic, and ultrastructural lesions associated with avian keratin disorder in Black-capped Chickadees (Poecile atricapillus)
An epizootic of beak abnormalities (avian keratin disorder) was recently detected among wild birds in Alaska. Here we describe the gross, histologic, and ultrastructural features of the disease in 30 affected adult black-capped chickadees (Poecile atricapillus). Grossly, there was elongation of the rhamphotheca, with varying degrees of lateral deviation, crossing, and gapping between the upper and
Authors
Caroline R. Van Hemert, A. G. Armién, J.E. Blake, Colleen M. Handel, T. M. O'Hara
Residency times and patterns of movement of postbreeding dunlin on a subarctic staging area in Alaska
Understanding how individuals use key resources is critical for effective conservation of a population. The Yukon-Kuskokwim Delta (YKD) in western Alaska is the most important postbreeding staging area for shorebirds in the subarctic North Pacific, yet little is known about movements of shorebirds there during the postbreeding period. To address this information gap, we studied residency times and
Authors
Nils Warnock, Colleen M. Handel, Robert E. Gill, Brian J. McCaffery
Evidence of accelerated beak growth associated with avian keratin disorder in black-capped chickadees (Poecile atricapillus)
We recently documented an epizootic of beak deformities in more than 2,000 Black-capped Chickadees (Poecile atricapillus) and other wild bird species in North America. This emerging avian disease, which has been termed avian keratin disorder, results in gross overgrowth of the rhamphotheca, the outer, keratinized layer of the beak. To test the hypothesis that the beak deformities characteristic of
Authors
Caroline R. Van Hemert, Colleen M. Handel, Todd M. O'Hara
Microanatomy of passerine hard-cornified tissues: Beak and claw structure of the black-capped chickadee (Poecile atricapillus)
The microanatomy of healthy beaks and claws in passerine birds has not been well described in the literature, despite the importance of these structures in avian life. Histological processing of hard‐cornified tissues is notoriously challenging and only a few reports on effective techniques have been published. An emerging epizootic of beak deformities among wild birds in Alaska and the Pacific No
Authors
Caroline R. Van Hemert, Colleen M. Handel, John E. Blake, Rhonda Swor, Todd M. O'Hara
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Science and Products
Filter Total Items: 90
Hemispheric-scale wind selection facilitates bar-tailed godwit circum-migration of the Pacific
The annual 29 000 km long migration of the bar-tailed godwit, Limosa lapponica baueri, around the Pacific Ocean traverses what is arguably the most complex and seasonally structured atmospheric setting on Earth. Faced with marked variation in wind regimes and storm conditions across oceanic migration corridors, individuals must make critical decisions about when and where to fly during nonstop fli
Authors
Robert E. Gill, David C. Douglas, Colleen M. Handel, T. Lee Tibbitts, Gary Hufford, Theunis Piersma
Reviving common standards in point-count surveys for broad inference across studies
We revisit the common standards recommended by Ralph et al. (1993, 1995a) for conducting point-count surveys to assess the relative abundance of landbirds breeding in North America. The standards originated from discussions among ornithologists in 1991 and were developed so that point-count survey data could be broadly compared and jointly analyzed by national data centers with the goals of monito
Authors
Steven M. Matsuoka, C. Lisa Mahon, Colleen M. Handel, Peter Solymos, Erin M. Bayne, Patricia C. Fontaine, C.J. Ralph
Wildlife health in a rapidly changing North: focus on avian disease
Climate-related environmental changes have increasingly been linked to emerging infectious diseases in wildlife. The Arctic is facing a major ecological transition that is expected to substantially affect animal and human health. Changes in phenology or environmental conditions that result from climate warming may promote novel species assemblages as host and pathogen ranges expand to previously u
Authors
Caroline R. Van Hemert, John M. Pearce, Colleen M. Handel
Coping with the cold: An ecological context for the abundance and distribution of rock sandpipers during winter in upper Cook Inlet, Alaska
Shorebirds are conspicuous and abundant at high northern latitudes during spring and summer, but as seasonal conditions deteriorate, few remain during winter. To the best of our knowledge, Cook Inlet, Alaska (60.6˚ N, 151.6˚ W), is the world’s coldest site that regularly supports wintering populations of shorebirds, and it is also the most northerly nonbreeding location for shorebirds in the Pacif
Authors
Daniel R. Ruthrauff, Robert E. Gill, T. Lee Tibbitts
Ecological correlates of variable organ sizes and fat loads in the most northerly-wintering shorebirds
Shorebirds at northern latitudes during the nonbreeding season typically carry relatively large lipid stores and exhibit an up-regulation of lean tissues associated with digestion and thermogenesis. Intraspecific variation in these tissues across sites primarily reflects differences in environmental conditions. Rock (Calidris ptilocnemis (Coues, 1873)) and Purple (Calidris maritima (Brünnich, 1764
Authors
Daniel R. Ruthrauff, Anne Dekinga, Robert E. Gill, R.W. Summers, Theunis Piersma
Intercontinental migratory connectivity and population structuring of Dunlins from western Alaska
The Dunlin (Calidris alpina) is a polytypic shorebird with complex patterns of distribution and migration throughout its holarctic range. We analyzed mark-re sighting data obtained between 1977 and 2010 from birds captured at two major staging areas in western Alaska to test the hypothesis that the migration patterns of Alaskan populations are a mixture of parallel and chain, similar to those of D
Authors
Robert E. Gill, Colleen M. Handel, Daniel R. Ruthrauff
Changing Arctic ecosystems--the role of ecosystem changes across the Boreal-Arctic transition zone on the distribution and abundance of wildlife populations
Arctic and boreal ecosystems provide important breeding habitat for more than half of North America’s migratory birds as well as many resident species. Northern landscapes are projected to experience more pronounced climate-related changes in habitat than most other regions. These changes include increases in shrub growth, conversion of tundra to forest, alteration of wetlands, shifts in species’
Authors
Lance McNew, Colleen M. Handel, John M. Pearce, Anthony R. DeGange, Leslie Holland-Bartels, Mary E. Whalen
Identical metabolic rate and thermal conductance in Rock Sandpiper (Calidris ptilocnemis) subspecies with contrasting nonbreeding life histories
Closely related species or subspecies can exhibit metabolic differences that reflect site-specific environmental conditions. Whether such differences represent fixed traits or flexible adjustments to local conditions, however, is difficult to predict across taxa. The nominate race of Rock Sandpiper (Calidris ptilocnemis) exhibits the most northerly nonbreeding distribution of any shorebird in the
Authors
Daniel R. Ruthrauff, Anne Dekinga, Robert E. Gill, Theunis Piersma
Macroscopic, histologic, and ultrastructural lesions associated with avian keratin disorder in Black-capped Chickadees (Poecile atricapillus)
An epizootic of beak abnormalities (avian keratin disorder) was recently detected among wild birds in Alaska. Here we describe the gross, histologic, and ultrastructural features of the disease in 30 affected adult black-capped chickadees (Poecile atricapillus). Grossly, there was elongation of the rhamphotheca, with varying degrees of lateral deviation, crossing, and gapping between the upper and
Authors
Caroline R. Van Hemert, A. G. Armién, J.E. Blake, Colleen M. Handel, T. M. O'Hara
Residency times and patterns of movement of postbreeding dunlin on a subarctic staging area in Alaska
Understanding how individuals use key resources is critical for effective conservation of a population. The Yukon-Kuskokwim Delta (YKD) in western Alaska is the most important postbreeding staging area for shorebirds in the subarctic North Pacific, yet little is known about movements of shorebirds there during the postbreeding period. To address this information gap, we studied residency times and
Authors
Nils Warnock, Colleen M. Handel, Robert E. Gill, Brian J. McCaffery
Evidence of accelerated beak growth associated with avian keratin disorder in black-capped chickadees (Poecile atricapillus)
We recently documented an epizootic of beak deformities in more than 2,000 Black-capped Chickadees (Poecile atricapillus) and other wild bird species in North America. This emerging avian disease, which has been termed avian keratin disorder, results in gross overgrowth of the rhamphotheca, the outer, keratinized layer of the beak. To test the hypothesis that the beak deformities characteristic of
Authors
Caroline R. Van Hemert, Colleen M. Handel, Todd M. O'Hara
Microanatomy of passerine hard-cornified tissues: Beak and claw structure of the black-capped chickadee (Poecile atricapillus)
The microanatomy of healthy beaks and claws in passerine birds has not been well described in the literature, despite the importance of these structures in avian life. Histological processing of hard‐cornified tissues is notoriously challenging and only a few reports on effective techniques have been published. An emerging epizootic of beak deformities among wild birds in Alaska and the Pacific No
Authors
Caroline R. Van Hemert, Colleen M. Handel, John E. Blake, Rhonda Swor, Todd M. O'Hara
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*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government