Nathan D Chelgren
I am a Wildlife Biologist at the USGS Forest and Rangeland Ecosystem Science Center
Science and Products
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Filter Total Items: 13
Stream Segments Captures and Crossings Associated With 2012 Aquatic Organism Passage Study Siuslaw National Forest Stream Segments Captures and Crossings Associated With 2012 Aquatic Organism Passage Study Siuslaw National Forest
Stream segments, aquatic organism captures, stream surveys, and road-stream crossings described by these metadata accompany a 2012 electrofishing study of the distribution and abundance of aquatic organisms (fish, lampreys, amphibians and crayfish), conducted by the U.S. Geological Survey, and the Pacific Northwest Region Aquatic and Riparian Ecosystem Monitoring Project (AREMP) of the U...
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Filter Total Items: 27
Comparison of electrofishing techniques to detect larval lampreys in wadeable streams in the Pacific Northwest Comparison of electrofishing techniques to detect larval lampreys in wadeable streams in the Pacific Northwest
We evaluated the probability of detecting larval lampreys using different methods of backpack electrofishing in wadeable streams in the U.S. Pacific Northwest. Our primary objective was to compare capture of lampreys using electrofishing with standard settings for salmon and trout to settings specifically adapted for capture of lampreys. Field work consisted of removal sampling by means...
Authors
Jason B. Dunham, Nathan D. Chelgren, Michael P. Heck, Steven M. Clark
Using multilevel spatial models to understand salamander site occupancy patterns after wildfire Using multilevel spatial models to understand salamander site occupancy patterns after wildfire
Studies of the distribution of elusive forest wildlife have suffered from the confounding of true presence with the uncertainty of detection. Occupancy modeling, which incorporates probabilities of species detection conditional on presence, is an emerging approach for reducing observation bias. However, the current likelihood modeling framework is restrictive for handling unexplained...
Authors
Nathan Chelgren, M. J. Adams, Larissa L. Bailey, R. Bruce Bury
Using spatiotemporal models and distance sampling to map the space use and abundance of newly metamorphosed Western Toads (Anaxyrus boreas) Using spatiotemporal models and distance sampling to map the space use and abundance of newly metamorphosed Western Toads (Anaxyrus boreas)
High variability in abundance, cryptic coloration, and small body size of newly metamorphosed anurans have limited demographic studies of this life-history stage. We used line-transect distance sampling and Bayesian methods to estimate the abundance and spatial distribution of newly metamorphosed Western Toads (Anaxyrus boreas) in terrestrial habitat surrounding a montane lake in central
Authors
Nathan D. Chelgren, Barbara Samora, M. J. Adams, Brome McCreary
Using occupancy models to understand the distribution of an amphibian pathogen, Batrachochytrium dendrobatidis Using occupancy models to understand the distribution of an amphibian pathogen, Batrachochytrium dendrobatidis
Batrachochytrium dendrobatidis is a fungal pathogen that is receiving attention around the world for its role in amphibian declines. Study of its occurrence patterns is hampered by false negatives: the failure to detect the pathogen when it is present. Occupancy models are a useful but currently underutilized tool for analyzing detection data when the probability of detecting a species...
Authors
M. J. Adams, Nathan Chelgren, David M. Reinitz, Rebecca A. Cole, L.J. Rachowicz, Stephanie Galvan, Brome McCreary, Christopher A. Pearl, Larissa L. Bailey, Jamie B. Bettaso, Evelyn L. Bull, Matthias Leu
Widespread occurrence of the chytrid fungus batrachochytrium dendrobatidis on oregon spotted frogs (rana pretiosa) Widespread occurrence of the chytrid fungus batrachochytrium dendrobatidis on oregon spotted frogs (rana pretiosa)
The pathogen Batrachochytrium dendrobatidis (Bd) has been associated with amphibian declines in multiple continents, including western North America. We investigated Bd prevalence in Oregon spotted frog (Rana pretiosa), a species that has declined across its range in the Pacific Northwest. Polymerase chain reaction analysis of skin swabs indicated that Bd was prevalent within populations...
Authors
C.A. Pearl, J. Bowerman, M.J. Adams, N.D. Chelgren
Demography and movement in a relocated population of Oregon Spotted Frogs (Rana pretiosa): Influence of season and gender Demography and movement in a relocated population of Oregon Spotted Frogs (Rana pretiosa): Influence of season and gender
We used five years of recapture data and Bayesian estimation to assess seasonal survival, movement, and growth of Oregon Spotted Frogs (Rana pretiosa) relocated into created ponds at Dilman Meadow in Oregon, USA. We evaluate hypotheses specific to the relocation and elucidate aspects of R. pretiosa life history that are poorly known. The odds of survival of relocated individuals during...
Authors
N.D. Chelgren, C.A. Pearl, M.J. Adams, J. Bowerman
Individual variation affects departure rate from the natal pond in an ephemeral pond-breeding anuran Individual variation affects departure rate from the natal pond in an ephemeral pond-breeding anuran
Frogs exhibit extreme plasticity and individual variation in growth and behavior during metamorphosis, driven by interactions of intrinsic state factors and extrinsic environmental factors. In northern red-legged frogs (Rana aurora Baird and Girard, 1852), we studied the timing of departure from the natal pond as it relates to date and size of individuals at metamorphosis in the context...
Authors
N.D. Chelgren, D.K. Rosenberg, S.S. Heppell, A.I. Gitelman
Fidelity and breeding probability related to population density and individual quality in black brent geese Branta bernicla nigricans Fidelity and breeding probability related to population density and individual quality in black brent geese Branta bernicla nigricans
1. Patterns of temporary emigration (associated with non-breeding) are important components of variation in individual quality. Permanent emigration from the natal area has important implications for both individual fitness and local population dynamics. 2. We estimated both permanent and temporary emigration of black brent geese (Branta bernicla nigricans Lawrence) from the Tutakoke...
Authors
James S. Sedinger, N.D. Chelgren, David H. Ward, M. S. Lindberg
Oregon Spotted Frog (Rana pretiosa) movement and demography at Dilman Meadow: Implications for future monitoring Oregon Spotted Frog (Rana pretiosa) movement and demography at Dilman Meadow: Implications for future monitoring
From 2001 to 2005, we studied the demography and seasonal movement of Oregon spotted frogs (Rana pretiosa) translocated into created ponds in Dilman Meadow in central Oregon. Our objectives were to inform future monitoring and management at the site, and to elucidate poorly known aspects of the species’ population ecology. Movement rates revealed complementary use of sites seasonally...
Authors
Nathan D. Chelgren, Christopher A. Pearl, Jay Bowerman, M. J. Adams
Survival and breeding advantages of larger Black Brant (Branta bernicla nigricans) goslings: Within- and among-cohort variation Survival and breeding advantages of larger Black Brant (Branta bernicla nigricans) goslings: Within- and among-cohort variation
We examined the relationship between mass late in the first summer and survival and return to the natal breeding colony for 12 cohorts (1986-1997) of female Black Brant (Branta bernicla nigricans). We used Cormack-Jolly-Seber methods and the program MARK to analyze capture-recapture data. Models included two kinds of residuals from regressions of mass on days after peak of hatch when...
Authors
J.S. Sedinger, N.D. Chelgren
Carryover aquatic effects on survival of metamorphic frogs during pond emigration Carryover aquatic effects on survival of metamorphic frogs during pond emigration
In organisms with complex life cycles, physiological stressors during early life stages may have fitness-level impacts that are delayed into later stages or habitats. We tested the hypothesis that body size and date of metamorphosis, which are highly responsive to aquatic stressors, influence post-metamorphic survival and movement patterns in the terrestrial phase of an ephemeral pond...
Authors
N.D. Chelgren, D.K. Rosenberg, S.S. Heppell, A.I. Gitelman
Effects of El Niño on distribution and reproductive performance of Black Brant Effects of El Niño on distribution and reproductive performance of Black Brant
Climate in low-latitude wintering areas may influence temperate and high-latitude breeding populations of birds, but demonstrations of such relationships have been rare because of difficulties in linking wintering with breeding populations. We used long-term aerial surveys in Mexican wintering areas and breeding areas in Alaska, USA, to assess numbers of Black Brant (Branta bernicla...
Authors
James S. Sedinger, David H. Ward, Jason L. Schamber, William I. Butler, William D. Eldridge, Bruce Conant, James F. Voelzer, Nathan Chelgren, Mark P. Herzog
Science and Products
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Filter Total Items: 13
Stream Segments Captures and Crossings Associated With 2012 Aquatic Organism Passage Study Siuslaw National Forest Stream Segments Captures and Crossings Associated With 2012 Aquatic Organism Passage Study Siuslaw National Forest
Stream segments, aquatic organism captures, stream surveys, and road-stream crossings described by these metadata accompany a 2012 electrofishing study of the distribution and abundance of aquatic organisms (fish, lampreys, amphibians and crayfish), conducted by the U.S. Geological Survey, and the Pacific Northwest Region Aquatic and Riparian Ecosystem Monitoring Project (AREMP) of the U...
If you are unable to access or download a product, email fresc_outreach@usgs.gov a request, including the full citation, or call (541) 750-1030.
Filter Total Items: 27
Comparison of electrofishing techniques to detect larval lampreys in wadeable streams in the Pacific Northwest Comparison of electrofishing techniques to detect larval lampreys in wadeable streams in the Pacific Northwest
We evaluated the probability of detecting larval lampreys using different methods of backpack electrofishing in wadeable streams in the U.S. Pacific Northwest. Our primary objective was to compare capture of lampreys using electrofishing with standard settings for salmon and trout to settings specifically adapted for capture of lampreys. Field work consisted of removal sampling by means...
Authors
Jason B. Dunham, Nathan D. Chelgren, Michael P. Heck, Steven M. Clark
Using multilevel spatial models to understand salamander site occupancy patterns after wildfire Using multilevel spatial models to understand salamander site occupancy patterns after wildfire
Studies of the distribution of elusive forest wildlife have suffered from the confounding of true presence with the uncertainty of detection. Occupancy modeling, which incorporates probabilities of species detection conditional on presence, is an emerging approach for reducing observation bias. However, the current likelihood modeling framework is restrictive for handling unexplained...
Authors
Nathan Chelgren, M. J. Adams, Larissa L. Bailey, R. Bruce Bury
Using spatiotemporal models and distance sampling to map the space use and abundance of newly metamorphosed Western Toads (Anaxyrus boreas) Using spatiotemporal models and distance sampling to map the space use and abundance of newly metamorphosed Western Toads (Anaxyrus boreas)
High variability in abundance, cryptic coloration, and small body size of newly metamorphosed anurans have limited demographic studies of this life-history stage. We used line-transect distance sampling and Bayesian methods to estimate the abundance and spatial distribution of newly metamorphosed Western Toads (Anaxyrus boreas) in terrestrial habitat surrounding a montane lake in central
Authors
Nathan D. Chelgren, Barbara Samora, M. J. Adams, Brome McCreary
Using occupancy models to understand the distribution of an amphibian pathogen, Batrachochytrium dendrobatidis Using occupancy models to understand the distribution of an amphibian pathogen, Batrachochytrium dendrobatidis
Batrachochytrium dendrobatidis is a fungal pathogen that is receiving attention around the world for its role in amphibian declines. Study of its occurrence patterns is hampered by false negatives: the failure to detect the pathogen when it is present. Occupancy models are a useful but currently underutilized tool for analyzing detection data when the probability of detecting a species...
Authors
M. J. Adams, Nathan Chelgren, David M. Reinitz, Rebecca A. Cole, L.J. Rachowicz, Stephanie Galvan, Brome McCreary, Christopher A. Pearl, Larissa L. Bailey, Jamie B. Bettaso, Evelyn L. Bull, Matthias Leu
Widespread occurrence of the chytrid fungus batrachochytrium dendrobatidis on oregon spotted frogs (rana pretiosa) Widespread occurrence of the chytrid fungus batrachochytrium dendrobatidis on oregon spotted frogs (rana pretiosa)
The pathogen Batrachochytrium dendrobatidis (Bd) has been associated with amphibian declines in multiple continents, including western North America. We investigated Bd prevalence in Oregon spotted frog (Rana pretiosa), a species that has declined across its range in the Pacific Northwest. Polymerase chain reaction analysis of skin swabs indicated that Bd was prevalent within populations...
Authors
C.A. Pearl, J. Bowerman, M.J. Adams, N.D. Chelgren
Demography and movement in a relocated population of Oregon Spotted Frogs (Rana pretiosa): Influence of season and gender Demography and movement in a relocated population of Oregon Spotted Frogs (Rana pretiosa): Influence of season and gender
We used five years of recapture data and Bayesian estimation to assess seasonal survival, movement, and growth of Oregon Spotted Frogs (Rana pretiosa) relocated into created ponds at Dilman Meadow in Oregon, USA. We evaluate hypotheses specific to the relocation and elucidate aspects of R. pretiosa life history that are poorly known. The odds of survival of relocated individuals during...
Authors
N.D. Chelgren, C.A. Pearl, M.J. Adams, J. Bowerman
Individual variation affects departure rate from the natal pond in an ephemeral pond-breeding anuran Individual variation affects departure rate from the natal pond in an ephemeral pond-breeding anuran
Frogs exhibit extreme plasticity and individual variation in growth and behavior during metamorphosis, driven by interactions of intrinsic state factors and extrinsic environmental factors. In northern red-legged frogs (Rana aurora Baird and Girard, 1852), we studied the timing of departure from the natal pond as it relates to date and size of individuals at metamorphosis in the context...
Authors
N.D. Chelgren, D.K. Rosenberg, S.S. Heppell, A.I. Gitelman
Fidelity and breeding probability related to population density and individual quality in black brent geese Branta bernicla nigricans Fidelity and breeding probability related to population density and individual quality in black brent geese Branta bernicla nigricans
1. Patterns of temporary emigration (associated with non-breeding) are important components of variation in individual quality. Permanent emigration from the natal area has important implications for both individual fitness and local population dynamics. 2. We estimated both permanent and temporary emigration of black brent geese (Branta bernicla nigricans Lawrence) from the Tutakoke...
Authors
James S. Sedinger, N.D. Chelgren, David H. Ward, M. S. Lindberg
Oregon Spotted Frog (Rana pretiosa) movement and demography at Dilman Meadow: Implications for future monitoring Oregon Spotted Frog (Rana pretiosa) movement and demography at Dilman Meadow: Implications for future monitoring
From 2001 to 2005, we studied the demography and seasonal movement of Oregon spotted frogs (Rana pretiosa) translocated into created ponds in Dilman Meadow in central Oregon. Our objectives were to inform future monitoring and management at the site, and to elucidate poorly known aspects of the species’ population ecology. Movement rates revealed complementary use of sites seasonally...
Authors
Nathan D. Chelgren, Christopher A. Pearl, Jay Bowerman, M. J. Adams
Survival and breeding advantages of larger Black Brant (Branta bernicla nigricans) goslings: Within- and among-cohort variation Survival and breeding advantages of larger Black Brant (Branta bernicla nigricans) goslings: Within- and among-cohort variation
We examined the relationship between mass late in the first summer and survival and return to the natal breeding colony for 12 cohorts (1986-1997) of female Black Brant (Branta bernicla nigricans). We used Cormack-Jolly-Seber methods and the program MARK to analyze capture-recapture data. Models included two kinds of residuals from regressions of mass on days after peak of hatch when...
Authors
J.S. Sedinger, N.D. Chelgren
Carryover aquatic effects on survival of metamorphic frogs during pond emigration Carryover aquatic effects on survival of metamorphic frogs during pond emigration
In organisms with complex life cycles, physiological stressors during early life stages may have fitness-level impacts that are delayed into later stages or habitats. We tested the hypothesis that body size and date of metamorphosis, which are highly responsive to aquatic stressors, influence post-metamorphic survival and movement patterns in the terrestrial phase of an ephemeral pond...
Authors
N.D. Chelgren, D.K. Rosenberg, S.S. Heppell, A.I. Gitelman
Effects of El Niño on distribution and reproductive performance of Black Brant Effects of El Niño on distribution and reproductive performance of Black Brant
Climate in low-latitude wintering areas may influence temperate and high-latitude breeding populations of birds, but demonstrations of such relationships have been rare because of difficulties in linking wintering with breeding populations. We used long-term aerial surveys in Mexican wintering areas and breeding areas in Alaska, USA, to assess numbers of Black Brant (Branta bernicla...
Authors
James S. Sedinger, David H. Ward, Jason L. Schamber, William I. Butler, William D. Eldridge, Bruce Conant, James F. Voelzer, Nathan Chelgren, Mark P. Herzog