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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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
Retrospective analysis of bottlenose dolphin foraging: a legacy of anthropogenic ecosystem disturbance
We used stable isotope analysis to investigate the foraging ecology of coastal bottlenose dolphins (Tursiops truncatus) in relation to a series of anthropogenic disturbances. We first demonstrated that stable isotopes are a faithful indicator of habitat use by comparing muscle isotope values to behavioral foraging data from the same individuals. δ13C values increased, while δ34S and δ15N values de
Authors
Sam Rossman, Nélio B. Barros, Peggy H. Ostrom, Craig A. Stricker, Aleta A. Hohn, Hasand Gandhi, Randall S. Wells
Mercury cycling in agricultural and managed wetlands of California: experimental evidence of vegetation-driven changes in sediment biogeochemistry and methylmercury production
The role of live vegetation in sediment methylmercury (MeHg) production and associated biogeochemistry was examined in three types of agricultural wetlands (domesticated or white rice, wild rice, and fallow fields) and adjacent managed natural wetlands (cattail- and bulrush or tule-dominated) in the Yolo Bypass region of California's Central Valley, USA. During the active growing season for each w
Authors
Lisamarie Windham-Myers, Mark Marvin-DiPasquale, Craig A. Stricker, Jennifer L. Agee, Le H. Kieu, Evangelos Kakouros
Mercury cycling in agricultural and managed wetlands of California: seasonal influences of vegetation on mercury methylation, storage, and transport
Plants are a dominant biologic and physical component of many wetland capable of influencing the internal pools and fluxes of methylmercury (MeHg). To investigate their role with respect to the latter, we examined the changing seasonal roles of vegetation biomass and Hg, C and N composition from May 2007-February 2008 in 3 types of agricultural wetlands (domesticated or white rice, wild rice, and
Authors
Lisamarie Windham-Myers, Mark C. Marvin-DiPasquale, Evangelos Kakouros, Jennifer L. Agee, Le H. Kieu, Craig A. Stricker, Jacob A. Fleck, Joshua T. Ackerman
Variation in hair δ13C and δ15N values in long-tailed macaques (Macaca fascicularis) from Singapore
Much of the primatology literature on stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) has focused on African and New World species, with comparatively little research published on Asian primates. Here we present hair δ13C and δ15N isotope values for a sample of 33 long-tailed macaques from Singapore. We evaluate the suggestion by a previous researcher that forest degradation and biodive
Authors
Michael A. Schillaci, J. Margaret Castellini, Craig A. Stricker, Lisa Jones-Engel, Benjamin P.Y.-H. Lee
The early bird gets the shrimp: Confronting assumptions of isotopic equilibrium and homogeneity in a wild bird population
1. Because stable isotope distributions in organic material vary systematically across energy gradients that exist in ecosystems, community and population structures, and in individual physiological systems, isotope values in animal tissues have helped address a broad range of questions in animal ecology. It follows that every tissue sample provides an isotopic profile that can be used to study di
Authors
Michael B. Wunder, Joseph R. Jehl, Craig A. Stricker
Carbon and sediment accumulation in the Everglades (USA) during the past 4000 years: rates, drivers, and sources of error
Tropical and sub-tropical wetlands are considered to be globally important sources for greenhouse gases but their capacity to store carbon is presumably limited by warm soil temperatures and high rates of decomposition. Unfortunately, these assumptions can be difficult to test across long timescales because the chronology, cumulative mass, and completeness of a sedimentary profile are often diffic
Authors
Paul H. Glaser, John C. Volin, Thomas J. Givnish, Barbara C. S. Hansen, Craig A. Stricker
Northern California Redwood Forests provide important seasonal habitat for migrant bats
No abstract available.
Authors
Theodore J. Weller, Craig A. Stricker
Effects of trophic level and metamorphosis on discrimination of hydrogen isotopes in a plant-herbivore system
The use of stable isotopes in ecological studies requires that we know the magnitude of discrimination factors between consumer and element sources. The causes of variation in discrimination factors for carbon and nitrogen have been relatively well studied. In contrast, the discrimination factors for hydrogen have rarely been measured. We grew cabbage looper caterpillars (Trichoplusia ni) on cabba
Authors
Jacob M. Peters, Nathan Wolf, Craig A. Stricker, Timothy R. Collier, Carlos Martinez del Rio
Pacific salmon (Oncorhynchus spp.) runs and consumer fitness: growth and energy storage in stream-dwelling salmonids increase with salmon spawner density
We examined how marine-derived nutrients (MDN), in the form of spawning Pacific salmon, influenced the nutritional status and δ15N of stream-dwelling fishes. We sampled juvenile coho salmon (Oncorhynchus kisutch) and Dolly Varden (Salvelinus malma) during spring and fall from 11 south-central Alaskan streams that ranged widely in spawning salmon biomass (0.1–4.7 kg·m–2). Growth rate (as indexed by
Authors
Daniel J. Rinella, Mark S. Wipfli, Craig A. Stricker, Ron A. Heintz, Matthew J. Rinella
Evidence of cryptic individual specialization in an opportunistic insectivorous bat
Habitat use and feeding behaviors of cryptic animals are often poorly understood. Analyses of stable isotope ratios in animal body tissues can help reveal an individual's location and resource use during tissue growth. We investigated variation in stable isotope ratios of 4 elements (H, C, N, and S) in the hair of a sedentary species of insectivorous bat (Eptesicus fuscus) inhabiting a chemically
Authors
Paul M. Cryan, Craig A. Stricker, Michael B. Wunder
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: 82
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
Retrospective analysis of bottlenose dolphin foraging: a legacy of anthropogenic ecosystem disturbance
We used stable isotope analysis to investigate the foraging ecology of coastal bottlenose dolphins (Tursiops truncatus) in relation to a series of anthropogenic disturbances. We first demonstrated that stable isotopes are a faithful indicator of habitat use by comparing muscle isotope values to behavioral foraging data from the same individuals. δ13C values increased, while δ34S and δ15N values de
Authors
Sam Rossman, Nélio B. Barros, Peggy H. Ostrom, Craig A. Stricker, Aleta A. Hohn, Hasand Gandhi, Randall S. Wells
Mercury cycling in agricultural and managed wetlands of California: experimental evidence of vegetation-driven changes in sediment biogeochemistry and methylmercury production
The role of live vegetation in sediment methylmercury (MeHg) production and associated biogeochemistry was examined in three types of agricultural wetlands (domesticated or white rice, wild rice, and fallow fields) and adjacent managed natural wetlands (cattail- and bulrush or tule-dominated) in the Yolo Bypass region of California's Central Valley, USA. During the active growing season for each w
Authors
Lisamarie Windham-Myers, Mark Marvin-DiPasquale, Craig A. Stricker, Jennifer L. Agee, Le H. Kieu, Evangelos Kakouros
Mercury cycling in agricultural and managed wetlands of California: seasonal influences of vegetation on mercury methylation, storage, and transport
Plants are a dominant biologic and physical component of many wetland capable of influencing the internal pools and fluxes of methylmercury (MeHg). To investigate their role with respect to the latter, we examined the changing seasonal roles of vegetation biomass and Hg, C and N composition from May 2007-February 2008 in 3 types of agricultural wetlands (domesticated or white rice, wild rice, and
Authors
Lisamarie Windham-Myers, Mark C. Marvin-DiPasquale, Evangelos Kakouros, Jennifer L. Agee, Le H. Kieu, Craig A. Stricker, Jacob A. Fleck, Joshua T. Ackerman
Variation in hair δ13C and δ15N values in long-tailed macaques (Macaca fascicularis) from Singapore
Much of the primatology literature on stable isotope ratios of carbon (δ13C) and nitrogen (δ15N) has focused on African and New World species, with comparatively little research published on Asian primates. Here we present hair δ13C and δ15N isotope values for a sample of 33 long-tailed macaques from Singapore. We evaluate the suggestion by a previous researcher that forest degradation and biodive
Authors
Michael A. Schillaci, J. Margaret Castellini, Craig A. Stricker, Lisa Jones-Engel, Benjamin P.Y.-H. Lee
The early bird gets the shrimp: Confronting assumptions of isotopic equilibrium and homogeneity in a wild bird population
1. Because stable isotope distributions in organic material vary systematically across energy gradients that exist in ecosystems, community and population structures, and in individual physiological systems, isotope values in animal tissues have helped address a broad range of questions in animal ecology. It follows that every tissue sample provides an isotopic profile that can be used to study di
Authors
Michael B. Wunder, Joseph R. Jehl, Craig A. Stricker
Carbon and sediment accumulation in the Everglades (USA) during the past 4000 years: rates, drivers, and sources of error
Tropical and sub-tropical wetlands are considered to be globally important sources for greenhouse gases but their capacity to store carbon is presumably limited by warm soil temperatures and high rates of decomposition. Unfortunately, these assumptions can be difficult to test across long timescales because the chronology, cumulative mass, and completeness of a sedimentary profile are often diffic
Authors
Paul H. Glaser, John C. Volin, Thomas J. Givnish, Barbara C. S. Hansen, Craig A. Stricker
Northern California Redwood Forests provide important seasonal habitat for migrant bats
No abstract available.
Authors
Theodore J. Weller, Craig A. Stricker
Effects of trophic level and metamorphosis on discrimination of hydrogen isotopes in a plant-herbivore system
The use of stable isotopes in ecological studies requires that we know the magnitude of discrimination factors between consumer and element sources. The causes of variation in discrimination factors for carbon and nitrogen have been relatively well studied. In contrast, the discrimination factors for hydrogen have rarely been measured. We grew cabbage looper caterpillars (Trichoplusia ni) on cabba
Authors
Jacob M. Peters, Nathan Wolf, Craig A. Stricker, Timothy R. Collier, Carlos Martinez del Rio
Pacific salmon (Oncorhynchus spp.) runs and consumer fitness: growth and energy storage in stream-dwelling salmonids increase with salmon spawner density
We examined how marine-derived nutrients (MDN), in the form of spawning Pacific salmon, influenced the nutritional status and δ15N of stream-dwelling fishes. We sampled juvenile coho salmon (Oncorhynchus kisutch) and Dolly Varden (Salvelinus malma) during spring and fall from 11 south-central Alaskan streams that ranged widely in spawning salmon biomass (0.1–4.7 kg·m–2). Growth rate (as indexed by
Authors
Daniel J. Rinella, Mark S. Wipfli, Craig A. Stricker, Ron A. Heintz, Matthew J. Rinella
Evidence of cryptic individual specialization in an opportunistic insectivorous bat
Habitat use and feeding behaviors of cryptic animals are often poorly understood. Analyses of stable isotope ratios in animal body tissues can help reveal an individual's location and resource use during tissue growth. We investigated variation in stable isotope ratios of 4 elements (H, C, N, and S) in the hair of a sedentary species of insectivorous bat (Eptesicus fuscus) inhabiting a chemically
Authors
Paul M. Cryan, Craig A. Stricker, Michael B. Wunder
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.