Craig Stricker, PhD
Craig Stricker is a Research Biologist at the Fort Collins Science Center.
Science and Products
Filter Total Items: 17
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Foraging habits in a generalist predator: sex and age influence habitat selection and resource use among bottlenose dolphins (Tursiops truncatus)
This study examines resource use (diet, habitat use, and trophic level) within and among demographic groups (males, females, and juveniles) of bottlenose dolphins (Tursiops truncatus). We analyzed the δ13C and δ15N values of 15 prey species constituting 84% of the species found in stomach contents. We used these data to establish a trophic enrichment factor (TEF) to inform dietary analysis using a
Authors
Sam Rossman, Elizabeth Berens McCabe, Nelio B. Barros, Hasand Gandhi, Peggy H. Ostrom, Craig A. Stricker, Randall S. Wells
Metamorphosis alters contaminants and chemical tracers in insects: implications for food webs
Insects are integral to most freshwater and terrestrial food webs, but due to their accumulation of environmental pollutants they are also contaminant vectors that threaten reproduction, development, and survival of consumers. Metamorphosis from larvae to adult can cause large chemical changes in insects, altering contaminant concentrations and fractionation of chemical tracers used to establish c
Authors
Johanna M. Kraus, David M. Walters, Jeff S. Wesner, Craig A. Stricker, Travis S. Schmidt, Robert E. Zuellig
Unexpected hydrogen isotope variation in oceanic pelagic seabirds
Hydrogen isotopes have significantly enhanced our understanding of the biogeography of migratory animals. The basis for this methodology lies in predictable, continental patterns of precipitation δD values that are often reflected in an organism’s tissues. δD variation is not expected for oceanic pelagic organisms whose dietary hydrogen (water and organic hydrogen in prey) is transferred up the fo
Authors
Peggy H. Ostrom, Anne E. Wiley, Sam Rossman, Craig A. Stricker, Helen F. James
Methylmercury production in sediment from agricultural and non-agricultural wetlands in the Yolo Bypass, California, USA
As part of a larger study of mercury (Hg) biogeochemistry and bioaccumulation in agricultural (rice growing) and non-agricultural wetlands in California's Central Valley, USA, seasonal and spatial controls on methylmercury (MeHg) production were examined in surface sediment. Three types of shallowly-flooded agricultural wetlands (white rice, wild rice, and fallow fields) and two types of managed (
Authors
Mark Marvin-DiPasquale, Lisamarie Windham-Myers, Jennifer L. Agee, Evangelos Kakouros, Le H. Kieu, Jacob A. Fleck, Charles N. Alpers, Craig A. Stricker
Selenium and mercury concentrations in harbor seals (Phoca vitulina) from central California: Health implications in an urbanized estuary
We measured total selenium and total mercury concentrations ([TSe] and [THg]) in hair (n = 138) and blood (n = 73) of harbor seals (Phoca vitulina) from California to assess variation by geography and sex, and inferred feeding relationships based on carbon, nitrogen, and sulfur stable isotopes. Harbor seals from Hg-contaminated sites had significantly greater [THg], and lesser [TSe] and TSe:THg mo
Authors
Elizabeth A. McHuron, James T. Harvey, J. Margaret Castellini, Craig A. Stricker, Todd M. O'Hara
Continental-scale, seasonal movements of a heterothermic migratory tree bat
Long-distance migration evolved independently in bats and unique migration behaviors are likely, but because of their cryptic lifestyles, many details remain unknown. North American hoary bats (Lasiurus cinereus cinereus) roost in trees year-round and probably migrate farther than any other bats, yet we still lack basic information about their migration patterns and wintering locations or strategi
Authors
Paul M. Cryan, Craig A. Stricker, Michael B. Wunder
Mercury cycling in agricultural and managed wetlands, Yolo Bypass, California: Spatial and seasonal variations in water quality
The seasonal and spatial variability of water quality, including mercury species, was evaluated in agricultural and managed, non-agricultural wetlands in the Yolo Bypass Wildlife Area, an area managed for multiple beneficial uses including bird habitat and rice farming. The study was conducted during an 11-month period (June 2007 to April 2008) that included a summer growing season and flooded con
Authors
Charles N. Alpers, Jacob A. Fleck, Mark C. Marvin-DiPasquale, Craig A. Stricker, Mark Stephenson, Howard E. Taylor
Mercury cycling in agricultural and managed wetlands: a synthesis of methylmercury production, hydrologic export, and bioaccumulation from an integrated field study
With seasonal wetting and drying, and high biological productivity, agricultural wetlands (rice paddies) may enhance the conversion of inorganic mercury (Hg(II)) to methylmercury (MeHg), the more toxic, organic form that biomagnifies through food webs. Yet, the net balance of MeHg sources and sinks in seasonal wetland environments is poorly understood because it requires an annual, integrated asse
Authors
Lisamarie Windham-Myers, Jacob A. Fleck, Joshua T. Ackerman, Mark C. Marvin-DiPasquale, Craig A. Stricker, Wesley A. Heim, Philip A.M. Bachand, Collin A. Eagles-Smith, Gary Gill, Mark Stephenson, Charles N. Alpers
Hydrogeochemistry of prairie pothole region wetlands: Role of long-term critical zone processes
This study addresses the geologic and hydrogeochemical processes operating at a range of scales within the prairie pothole region (PPR). The PPR is a 750,000 km2portion of north central North America that hosts millions of small wetlands known to be critical habitat for waterfowl and other wildlife. At a local scale, we characterized the geochemical evolution of the 92-ha Cottonwood Lake study are
Authors
Martin B. Goldhaber, Christopher T. Mills, Jean Morrison, Craig A. Stricker, David M. Mushet, James W. LaBaugh
Holocene dynamics of the Florida Everglades with respect to climate, dustfall, and tropical storms
Aeolian dust is rarely considered an important source for nutrients in large peatlands, which generally develop in moist regions far from the major centers of dust production. As a result, past studies assumed that the Everglades provides a classic example of an originally oligotrophic, P-limited wetland that was subsequently degraded by anthropogenic activities. However, a multiproxy sedimentary
Authors
Paul H. Glaser, Barbara C. S. Hansen, Joseph J. Donovan, Thomas J. Givnish, Craig A. Stricker, John C. Volin
Mercury in gray wolves (Canis lupus) in Alaska: Increased exposure through consumption of marine prey
Mercury (Hg) bioaccumulates in the tissues of organismsand biomagnifies within food-webs. Graywolves (Canis lupus) in Alaska primarily acquire Hg through diet; therefore, comparing the extent of Hg exposure inwolves, in conjunction with stable isotopes, from interior and coastal regions of Alaska offers important insight into their feeding ecology. Liver, kidney, and skeletal muscle samples from
Authors
Ashley K. McGrew, Lora R. Ballweber, Sara K. Moses, Craig A. Stricker, Kimberlee B. Beckmen, Mo D. Salman, Todd M. O’Hara
Seasonal persistence of marine-derived nutrients in south-central Alaskan salmon streams
Spawning salmon deliver annual pulses of marine-derived nutrients (MDN) to riverine ecosystems around the Pacific Rim, leading to increased growth and condition in aquatic and riparian biota. The influence of pulsed resources may last for extended periods of time when recipient food webs have effective storage mechanisms, yet few studies have tracked the seasonal persistence of MDN. With this as o
Authors
Daniel J. Rinella, Mark S. Wipfi, Coowe M. Walker, Craig A. Stricker, Ron A. Heintz
Non-USGS Publications**
Burton, T.M., Uzarski, D.G., Gathman, J.P. et al. Wetlands (1999) 19: 869. doi:10.1007/BF03161789
Uzarski, D., Burton, T. & Stricker, C. Hydrobiologia (2001) 455: 137. doi:10.1023/A:1011929719866
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 17
No Result Found
Filter Total Items: 83
Foraging habits in a generalist predator: sex and age influence habitat selection and resource use among bottlenose dolphins (Tursiops truncatus)
This study examines resource use (diet, habitat use, and trophic level) within and among demographic groups (males, females, and juveniles) of bottlenose dolphins (Tursiops truncatus). We analyzed the δ13C and δ15N values of 15 prey species constituting 84% of the species found in stomach contents. We used these data to establish a trophic enrichment factor (TEF) to inform dietary analysis using a
Authors
Sam Rossman, Elizabeth Berens McCabe, Nelio B. Barros, Hasand Gandhi, Peggy H. Ostrom, Craig A. Stricker, Randall S. Wells
Metamorphosis alters contaminants and chemical tracers in insects: implications for food webs
Insects are integral to most freshwater and terrestrial food webs, but due to their accumulation of environmental pollutants they are also contaminant vectors that threaten reproduction, development, and survival of consumers. Metamorphosis from larvae to adult can cause large chemical changes in insects, altering contaminant concentrations and fractionation of chemical tracers used to establish c
Authors
Johanna M. Kraus, David M. Walters, Jeff S. Wesner, Craig A. Stricker, Travis S. Schmidt, Robert E. Zuellig
Unexpected hydrogen isotope variation in oceanic pelagic seabirds
Hydrogen isotopes have significantly enhanced our understanding of the biogeography of migratory animals. The basis for this methodology lies in predictable, continental patterns of precipitation δD values that are often reflected in an organism’s tissues. δD variation is not expected for oceanic pelagic organisms whose dietary hydrogen (water and organic hydrogen in prey) is transferred up the fo
Authors
Peggy H. Ostrom, Anne E. Wiley, Sam Rossman, Craig A. Stricker, Helen F. James
Methylmercury production in sediment from agricultural and non-agricultural wetlands in the Yolo Bypass, California, USA
As part of a larger study of mercury (Hg) biogeochemistry and bioaccumulation in agricultural (rice growing) and non-agricultural wetlands in California's Central Valley, USA, seasonal and spatial controls on methylmercury (MeHg) production were examined in surface sediment. Three types of shallowly-flooded agricultural wetlands (white rice, wild rice, and fallow fields) and two types of managed (
Authors
Mark Marvin-DiPasquale, Lisamarie Windham-Myers, Jennifer L. Agee, Evangelos Kakouros, Le H. Kieu, Jacob A. Fleck, Charles N. Alpers, Craig A. Stricker
Selenium and mercury concentrations in harbor seals (Phoca vitulina) from central California: Health implications in an urbanized estuary
We measured total selenium and total mercury concentrations ([TSe] and [THg]) in hair (n = 138) and blood (n = 73) of harbor seals (Phoca vitulina) from California to assess variation by geography and sex, and inferred feeding relationships based on carbon, nitrogen, and sulfur stable isotopes. Harbor seals from Hg-contaminated sites had significantly greater [THg], and lesser [TSe] and TSe:THg mo
Authors
Elizabeth A. McHuron, James T. Harvey, J. Margaret Castellini, Craig A. Stricker, Todd M. O'Hara
Continental-scale, seasonal movements of a heterothermic migratory tree bat
Long-distance migration evolved independently in bats and unique migration behaviors are likely, but because of their cryptic lifestyles, many details remain unknown. North American hoary bats (Lasiurus cinereus cinereus) roost in trees year-round and probably migrate farther than any other bats, yet we still lack basic information about their migration patterns and wintering locations or strategi
Authors
Paul M. Cryan, Craig A. Stricker, Michael B. Wunder
Mercury cycling in agricultural and managed wetlands, Yolo Bypass, California: Spatial and seasonal variations in water quality
The seasonal and spatial variability of water quality, including mercury species, was evaluated in agricultural and managed, non-agricultural wetlands in the Yolo Bypass Wildlife Area, an area managed for multiple beneficial uses including bird habitat and rice farming. The study was conducted during an 11-month period (June 2007 to April 2008) that included a summer growing season and flooded con
Authors
Charles N. Alpers, Jacob A. Fleck, Mark C. Marvin-DiPasquale, Craig A. Stricker, Mark Stephenson, Howard E. Taylor
Mercury cycling in agricultural and managed wetlands: a synthesis of methylmercury production, hydrologic export, and bioaccumulation from an integrated field study
With seasonal wetting and drying, and high biological productivity, agricultural wetlands (rice paddies) may enhance the conversion of inorganic mercury (Hg(II)) to methylmercury (MeHg), the more toxic, organic form that biomagnifies through food webs. Yet, the net balance of MeHg sources and sinks in seasonal wetland environments is poorly understood because it requires an annual, integrated asse
Authors
Lisamarie Windham-Myers, Jacob A. Fleck, Joshua T. Ackerman, Mark C. Marvin-DiPasquale, Craig A. Stricker, Wesley A. Heim, Philip A.M. Bachand, Collin A. Eagles-Smith, Gary Gill, Mark Stephenson, Charles N. Alpers
Hydrogeochemistry of prairie pothole region wetlands: Role of long-term critical zone processes
This study addresses the geologic and hydrogeochemical processes operating at a range of scales within the prairie pothole region (PPR). The PPR is a 750,000 km2portion of north central North America that hosts millions of small wetlands known to be critical habitat for waterfowl and other wildlife. At a local scale, we characterized the geochemical evolution of the 92-ha Cottonwood Lake study are
Authors
Martin B. Goldhaber, Christopher T. Mills, Jean Morrison, Craig A. Stricker, David M. Mushet, James W. LaBaugh
Holocene dynamics of the Florida Everglades with respect to climate, dustfall, and tropical storms
Aeolian dust is rarely considered an important source for nutrients in large peatlands, which generally develop in moist regions far from the major centers of dust production. As a result, past studies assumed that the Everglades provides a classic example of an originally oligotrophic, P-limited wetland that was subsequently degraded by anthropogenic activities. However, a multiproxy sedimentary
Authors
Paul H. Glaser, Barbara C. S. Hansen, Joseph J. Donovan, Thomas J. Givnish, Craig A. Stricker, John C. Volin
Mercury in gray wolves (Canis lupus) in Alaska: Increased exposure through consumption of marine prey
Mercury (Hg) bioaccumulates in the tissues of organismsand biomagnifies within food-webs. Graywolves (Canis lupus) in Alaska primarily acquire Hg through diet; therefore, comparing the extent of Hg exposure inwolves, in conjunction with stable isotopes, from interior and coastal regions of Alaska offers important insight into their feeding ecology. Liver, kidney, and skeletal muscle samples from
Authors
Ashley K. McGrew, Lora R. Ballweber, Sara K. Moses, Craig A. Stricker, Kimberlee B. Beckmen, Mo D. Salman, Todd M. O’Hara
Seasonal persistence of marine-derived nutrients in south-central Alaskan salmon streams
Spawning salmon deliver annual pulses of marine-derived nutrients (MDN) to riverine ecosystems around the Pacific Rim, leading to increased growth and condition in aquatic and riparian biota. The influence of pulsed resources may last for extended periods of time when recipient food webs have effective storage mechanisms, yet few studies have tracked the seasonal persistence of MDN. With this as o
Authors
Daniel J. Rinella, Mark S. Wipfi, Coowe M. Walker, Craig A. Stricker, Ron A. Heintz
Non-USGS Publications**
Burton, T.M., Uzarski, D.G., Gathman, J.P. et al. Wetlands (1999) 19: 869. doi:10.1007/BF03161789
Uzarski, D., Burton, T. & Stricker, C. Hydrobiologia (2001) 455: 137. doi:10.1023/A:1011929719866
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.