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Craig Stricker, PhD

Craig Stricker is a Research Biologist at the Fort Collins Science Center. 

Science and Products

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Fort Collins Science Center

Fort Collins Science Center Labs and Facilities

The Fort Collins Science Center has scientists working in several diverse locations as well as three in house highly specialized laboratories, studying subjects from molecular ecology to brown treesnakes, dendroecology to streamflows, and macroinvertebrate species to Burmese pythons. Our extraordinary scientists work in each of these locations advancing studies in their particluar areas of study...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center
link

Fort Collins Science Center Labs and Facilities

The Fort Collins Science Center has scientists working in several diverse locations as well as three in house highly specialized laboratories, studying subjects from molecular ecology to brown treesnakes, dendroecology to streamflows, and macroinvertebrate species to Burmese pythons. Our extraordinary scientists work in each of these locations advancing studies in their particluar areas of study...
Learn More
link
Two scientists work on a study of mercury contamination in the water.

Contaminant Biology: Stable Isotope Applications

Environmental contaminants of natural and anthropogenic origin represent a major stressor to ecosystems, including human and wildlife populations.
By
Fort Collins Science Center
link

Contaminant Biology: Stable Isotope Applications

Environmental contaminants of natural and anthropogenic origin represent a major stressor to ecosystems, including human and wildlife populations.
Learn More
link
Seemingly Surreal Swallows in a Spring Snowstorm, by Keith Williams.

Biogeography: Stable Isotope Applications

The distribution of species across the landscape is of great interest to conservation biology. Habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences. However, for species with cryptic or migratory life histories, we often lack sufficient detail about habitat usage and in many cases...
By
Fort Collins Science Center
link

Biogeography: Stable Isotope Applications

The distribution of species across the landscape is of great interest to conservation biology. Habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences. However, for species with cryptic or migratory life histories, we often lack sufficient detail about habitat usage and in many cases...
Learn More
link
Waterfall in Appalachian Forest

Biogeochemistry: Stable Isotope Applications

Biogeochemical cycling is a cornerstone of ecosystem function and structure. Much has been learned about element cycles in a variety of systems using standard geochemical techniques.
By
Fort Collins Science Center
link

Biogeochemistry: Stable Isotope Applications

Biogeochemical cycling is a cornerstone of ecosystem function and structure. Much has been learned about element cycles in a variety of systems using standard geochemical techniques.
Learn More
link
The sunset on the main city beach in Laguna Beach, CA.

Ecological Applications of Stable Isotopes

Environmental contaminants of natural and anthropogenic origin represent a major stressor to ecosystems, including human and wildlife populations. FORT scientists are studying these stressors in order to understand the contaminant cycling under natural environmental conditions. Stable isotope techniques are extremely useful in resolving trophic pathways by which contaminants become bioavailable...
By
Land Management Research Program, Fort Collins Science Center
link

Ecological Applications of Stable Isotopes

Environmental contaminants of natural and anthropogenic origin represent a major stressor to ecosystems, including human and wildlife populations. FORT scientists are studying these stressors in order to understand the contaminant cycling under natural environmental conditions. Stable isotope techniques are extremely useful in resolving trophic pathways by which contaminants become bioavailable...
Learn More
link
A polar bear in a pool.

Foraging Ecology Using Stable Isotopes

Understanding species habitat requirements is incomplete without insight into nutrition, including various aspects of foraging ecology. Traditional diet studies can be challenging because of logistics, issues related to resource availability, and observations are often short-term in nature based on gut contents or scat. Additionally, perturbations such as species introductions, habitat degradation...
By
Land Management Research Program, Species Management Research Program, Fort Collins Science Center
link

Foraging Ecology Using Stable Isotopes

Understanding species habitat requirements is incomplete without insight into nutrition, including various aspects of foraging ecology. Traditional diet studies can be challenging because of logistics, issues related to resource availability, and observations are often short-term in nature based on gut contents or scat. Additionally, perturbations such as species introductions, habitat degradation...
Learn More
Filter Total Items: 17

Geochemical Analyses of Water, Mine tailings, Fluvial Suspended Sediments, Fluvial Bed Sediments, and Fluvial Flood Deposit Sediments from the Big River and Meramec River Drainage Basins, Missouri

Geochemical data for aqueous, mine tailings, and sediment samples collected from the Big River and Meramec River drainage basins in southeastern Missouri are presented. The Big River drains historical lead, zinc, and barite mining districts, including the Old Lead Belt (OLB). Underground mining in the OLB resulted in large mine-waste chat piles and tailings impoundments that have released material
By
Central Midwest Water Science Center

Laboratory analyses for fish tissue from Lake Koocanusa and Kootenai River Basin, Montana, 2022

This data release includes laboratory analyses for fish tissue samples collected from Lake Koocanusa and the Kootenai River Basin in Montana during 2022. Samples were collected by the U.S. Geological Survey Wyoming-Montana Water Science Center in cooperation with Montana Fish, Wildlife and Parks and Montana Department of Environmental Quality. Analyses include histology, percent moisture, and 30 e
By
Wyoming-Montana Water Science Center

Silicified wood from around Old Faithful Geyser, Yellowstone National Park

Old Faithful Geyser in the Upper Geyser Basin of Yellowstone National Park is one of the best studied geysers in the world. Under research permit YELL-SCI-8030, samples from 13 silicified tree remnants were collected adjacent to the Old Faithful Geyser cone in April and November 2019. The silicified wood samples were dated using the radiocarbon (14C) method and were analyzed by scanning electron m
By
Volcano Science Center

Modeled Pacific salmon escapement biomass and nutrient and contaminant concentrations across western North America, 1976-2015

The data contain yearly modeled estimates of Pacific salmon escapement (in annual metric tons of wet mass) from 1976 to 2015 across four regions of western North America. A second data file contains modeled estimates of contaminant or nutrient concentrations in Pacific Salmon. The modeled estimates were derived from Bayesian generalized linear models (contaminant or nutrient concentrations) or fro
By
Columbia Environmental Research Center

Total mercury, methylmercury, and isotopic composition in various life stages of boreal chorus frogs (Pseudacris maculata) at two subalpine ponds in the Rocky Mountains, CO, USA, 2015

Mercury is an atmospherically transported contaminant found even in relatively pristine habitats. Once accumulated at the base of the food web, mercury can move between animals that are linked trophically. Pond-breeding amphibians may be particularly important vectors of mercury flux from remote freshwater to terrestrial systems because they feed on algae and detritus as tadpoles and metamorphose
By
Columbia Environmental Research Center

Mercury concentrations, isotopic composition, biomass, and taxonomy of stream and riparian organisms in the vicinity of Yellow Pine, Idaho, 2015-2016.

This data release includes sampling location data; field-collected stream attribute data; laboratory-analyzed chemistry concentrations (total mercury, methyl mercury) and isotopic composition (total mercury, carbon, and nitrogen) for stream biota (seston, periphyton, benthic insects, emerging adult insects, riparian spiders, and fish); density, body length, and taxonomic information for benthic in
By
Mineral Resources Program, Columbia Environmental Research Center, Geology, Geophysics, and Geochemistry Science Center

Dataset for temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river

The trace element selenium is an essential element with a narrow window between concentrations needed to support life and those that cause toxicity to egg laying organisms. Selenium bioaccumulation in aquatic organisms is primarily the result of trophic transfer through food webs and is poorly predicted by dissolved concentrations in freshwater bodies. To better understand the hydrologic and biolo
By
Wyoming-Montana Water Science Center

Chemistry of water, stream sediment, wildfire ash, soil, dust, and mine waste for Fourmile Creek Watershed, Colorado, 2010-2019

In response to the 2010 Fourmile Canyon fire near Boulder, Colorado, the U.S. Geological Survey collected data to support investigations into the magnitude and critical drivers of water-quality impairment after wildfire. We analyzed chemistry of stream water, sediment, wildfire ash, soil, dust, and mine waste for metals and other parameters in order to evaluate the effects of legacy mining and wil
By
Water Resources Mission Area

Radiogenic strontium isotope data for non-native walleye otoliths collected from select areas of the Upper Colorado River Basin

This dataset includes radiogenic strontium isotope compositions of non-native walleye otoliths collected from select areas of the Upper Colorado River Basin (UCRB). Strontium isotope data have been widely used to assess natal areas for a variety of fish species. Following on previous work, this project sought to fill data gaps for walleye collected from the Colorado River (river miles 11-109.3), t
By
Fort Collins Science Center

Stable carbon isotope and wood component concentration data for riparian cottonwood tree rings, Little Missouri River, North Dakota

This dataset includes stable carbon isotope values, lignin, cellulose, and hemicellulose concentrations (expressed as percent of ash-free dry mass) for riparian cottonwood (Populus deltoides) tree rings growing on the Little Missouri River floodplain, Theodore Roosevelt National Park, North Dakota. Drought stress induces stomatal closure and the carbon isotope ratio of annual tree rings tends to
By
Fort Collins Science Center

Stable carbon and nitrogen isotope data for Siberian barn swallow subspecies collected during the breeding season

This dataset includes stable carbon and nitrogen isotope values for the inner tail retrices of three subspecies of barn swallow (Hirundo rustica rustica, H. r. tytleri, and H. r. gutturalis). Sampling was conducted in Russia (summer 2013), China (summer 2014), Mongolia (summer 2014), Japan (summer 2014), and western China (summer 2015) using mist nets. Stable carbon and nitrogen isotope data are u
By
Fort Collins Science Center

Ovary mass and stable hydrogen isotope data for resident and migratory female dark-eyed juncos

This dataset includes ovary mass and stable hydrogen isotope compositions of feathers and claws from resident and migratory female dark-eyed juncos (Junco hyemalis) collected during early spring at Mountain Lake Biological Station, Pembroke, Virginia. A total of 18 migrant and 15 resident female dark-eyed juncos, a songbird that exhibits seasonal sympatry, were caught during March-April. Stable hy
By
Fort Collins Science Center
No results found.
Filter Total Items: 81

Design, development, and implementation of IsoBank: A centralized repository for isotopic data

Stable isotope data have made pivotal contributions to nearly every discipline of the physical and natural sciences. As the generation and application of stable isotope data continues to grow exponentially, so does the need for a unifying data repository to improve accessibility and promote collaborative engagement. This paper provides an overview of the design, development, and implementation of
Authors
Oliver N. Shipley, Anna J. Dabrowski, Gabriel J. Bowen, Brian Hayden, Jonathan N. Pauli, Christopher Jordan, Lesleigh Anderson, Adriana Bailey, Clement P. Bataille, Carla Cicero, Hilary G. Close, Craig Cook, Joseph A. Cook, Ankur R. Desai, Jaivime Evaristo, Tim R. Filley, Christine A.M. France, Sora Lee Kim, Sebastian H. Kopf, Julie Loisel, Philip J. Manlick, Jamie M. McFarlin, Bailey C. McMeans, Tamsin C. O'Connel, Brice X. Semmens, Chris Stantis, Paul Szejner, Suzanne E. Pilaar Birch, Annie L. Putman, Craig A. Stricker, Tara L.E. Trammell, Mark D. Uhen, Samantha Weintraub-Leff, Matthew J. Wooller, John W. Williams, Christopher T. Yarnes, Hanna B. Vander Zanden, Seth D. Newsome
By
Ecosystems Mission Area, Water Resources Mission Area, Fort Collins Science Center, Utah Water Science Center

Geographic distribution of feather δ34S in Europe

Geographic distribution models of environmentally stable isotopes (the so-called “isoscapes”) are widely employed in animal ecology, and wildlife forensics and conservation. However, the application of isoscapes is limited to elements and regions for which the spatial patterns have been estimated. Here, we focused on the ubiquitous yet less commonly used stable sulfur isotopes (δ34S). To predict t
Authors
Vojtěch Brlík, Petr Procházka, Luana Bontempo, Federica Camin, Frédéric Jiguet, Gergely Osváth, Craig A. Stricker, Michael B. Wunder, Rebecca L. Powell
By
Ecosystems Mission Area, Fort Collins Science Center

Complex life histories alter patterns of mercury exposure and accumulation in a pond-breeding amphibian

Quantifying how contaminants change across life cycles of species that undergo metamorphosis is critical to assessing organismal risk, particularly for consumers. Pond-breeding amphibians can dominate aquatic animal biomass as larvae and are terrestrial prey as juveniles and adults. Thus, amphibians can be vectors of mercury exposure in both aquatic and terrestrial food webs. However, it is still
Authors
Freya Elizabeth Rowland, Erin L. Muths, Collin A. Eagles-Smith, Craig A. Stricker, Johanna M. Kraus, Rachel A. Harrington, David Walters
By
Ecosystems Mission Area, Columbia Environmental Research Center, Fort Collins Science Center

Animal tracing with sulfur isotopes: Spatial segregation and climate variability in Africa likely contribute to population trends of a migratory songbird

Climatic conditions affect animals but range-wide impacts at the population level remain largely unknown, especially in migratory species. However, studying climate–population relationships is still challenging in small migrants due to a lack of efficient and cost-effective geographic tracking method.Spatial distribution patterns of environmental stable isotopes (so called ‘isoscapes’) generally o
Authors
Vojtech Brlik, Petr Prochazka, Bengt Hansson, Craig A. Stricker, Elizabeth Yohannes, Rebecca L Powell, Michael B. Wunder
By
Ecosystems Mission Area, Fort Collins Science Center

Diet energy density estimated from isotopes in predator hair associated with survival, habitat, and population dynamics

Sea ice loss is fundamentally altering the Arctic marine environment. Yet there is a paucity of data on the adaptability of food webs to ecosystem change, including predator-prey interactions. Polar bears (Ursus maritimus) are an important subsistence resource for Indigenous people and an apex predator that relies entirely on the under-ice food web to meet their energy needs. Here, we assessed whe
Authors
Karyn D. Rode, Brian D. Taras, Craig A. Stricker, Todd C. Atwood, Nicole P Boucher, George M. Durner, Andrew E. Derocher, Evan S. Richardson, Seth Cherry, Lori T. Quakenbush, Lara Horstmann, Jeffrey F. Bromaghin
By
Ecosystems Mission Area, Alaska Science Center, Fort Collins Science Center

Summer/fall diet and macronutrient assimilation in an Arctic predator

Free-ranging predator diet estimation is commonly achieved by applying molecular-based tracers because direct observation is not logistically feasible or robust. However, tracers typically do not represent all dietary macronutrients, which likely obscures resource use as prey proximate composition varies and tissue consumption can be specific. For example, polar bears (Ursus maritimus) preferentia
Authors
Craig A. Stricker, Karyn D. Rode, Brian D. Taras, Jeffrey F. Bromaghin, Lara Horstmann, Lori T. Quakenbush
By
Ecosystems Mission Area, Alaska Science Center, Fort Collins Science Center

Increased mercury and reduced insect diversity in linked stream-riparian food webs downstream of a historical mercury mine

Historical mining left a legacy of abandoned mines and waste rock in remote headwaters of major river systems in the western United States. Understanding the influence of these legacy mines on culturally and ecological important downstream ecosystems is not always straight-forward because of elevated natural levels of mineralization in mining-impacted watersheds. To test the ecological effects of
Authors
Johanna M. Kraus, JoAnn Holloway, Michael Pribil, Ben N. Mcgee, Craig A. Stricker, Danny Rutherford, Andrew S. Todd
By
Ecosystems Mission Area, Columbia Environmental Research Center

The reuse of avian samples: Opportunities, pitfalls and a solution

Tissue samples are frequently collected to study various aspects of avian biology, but in many cases these samples are not used in their entirety and are stored by the collector. The already collected samples provide a largely overlooked opportunity because they can be used by different researchers in different biological fields. Broad reuse of samples could result in multispecies or large-scale s
Authors
Vojtěch Brlík, Pavel Pipek, Kate Brandis, Nikita Chernetsov, Fábio J. V. Costa, L. Gerardo Herrera M., Yosef Kiat, Richard B. Lanctot, Peter P. Marra, D. Ryan Norris, Chima J. Nwaogu, Petra Quillfeldt, Sarah T. Saalfeld, Craig A. Stricker, Robert L. Thomson, Tianhao Zhao, Petr Procházka
By
Ecosystems Mission Area, Fort Collins Science Center

Energetic and health effects of protein overconsumption constrain dietary adaptation in an apex predator

Studies of predator feeding ecology commonly focus on energy intake. However, captive predators have been documented to selectively feed to optimize macronutrient intake. As many apex predators experience environmental changes that affect prey availability, limitations on selective feeding can affect energetics and health. We estimated the protein:fat ratio of diets consumed by wild polar bears us
Authors
Karyn D. Rode, Charles T. Robbins, Craig A. Stricker, Brian D. Taras, Troy N Tollefson
By
Ecosystems Mission Area, Alaska Science Center, Fort Collins Science Center

Temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river

Hydrologic and irrigation regimes mediate the timing of selenium (Se) mobilization to rivers, but the extent to which patterns in Se uptake and trophic transfer through recipient food webs reflect the temporal variation in Se delivery is unknown. We investigated Se mobilization, partitioning, and trophic transfer along approximately 60 river miles of the selenium-impaired segment of the Lower Gunn
Authors
Jessica E Brandt, James Roberts, Craig A. Stricker, Holly Rogers, Patricia Nease, Travis S. Schmidt
By
Ecosystems Mission Area, Water Resources Mission Area, Fort Collins Science Center, Great Lakes Science Center, Wyoming-Montana Water Science Center

Breeding at higher latitude is associated with higher photoperiodic threshold and delayed reproductive development in a songbird

Many seasonally breeding animals exhibit a threshold day length (critical photoperiod; CPP) for gonadal growth, and populations breeding at higher latitudes typically have a higher CPP. Much less is known about latitudinal variation in CPP in migratory population that winter away from their breeding range and must time their reproduction to match favorable conditions at their destination. To addre
Authors
Devraj Singh, S. M. Reed, A. A. Kimmitt, K. A. Alford, Craig A. Stricker, P. D. Polly, Ellen D. Ketterson
By
Ecosystems Mission Area, Fort Collins Science Center

Evidence of post-breeding prospecting in a long-distance migrant.

Organisms assess biotic and abiotic cues at multiple sites when deciding where to settle. However, due to temporal constraints on this prospecting, the suitability of available habitat may be difficult for an individual to assess when cues are most reliable, or at the time they are making settlement decisions. For migratory birds, the postbreeding season may be the optimal time to prospect and inf
Authors
Max Ciaglo, Ross Calhoun, Scott W Yanco, Michael B. Wunder, Craig A. Stricker, Brian D Linkhart
By
Ecosystems Mission Area, Fort Collins Science Center

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

link
Fort Collins Science Center

Fort Collins Science Center Labs and Facilities

The Fort Collins Science Center has scientists working in several diverse locations as well as three in house highly specialized laboratories, studying subjects from molecular ecology to brown treesnakes, dendroecology to streamflows, and macroinvertebrate species to Burmese pythons. Our extraordinary scientists work in each of these locations advancing studies in their particluar areas of study...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, Fort Collins Science Center
link

Fort Collins Science Center Labs and Facilities

The Fort Collins Science Center has scientists working in several diverse locations as well as three in house highly specialized laboratories, studying subjects from molecular ecology to brown treesnakes, dendroecology to streamflows, and macroinvertebrate species to Burmese pythons. Our extraordinary scientists work in each of these locations advancing studies in their particluar areas of study...
Learn More
link
Two scientists work on a study of mercury contamination in the water.

Contaminant Biology: Stable Isotope Applications

Environmental contaminants of natural and anthropogenic origin represent a major stressor to ecosystems, including human and wildlife populations.
By
Fort Collins Science Center
link

Contaminant Biology: Stable Isotope Applications

Environmental contaminants of natural and anthropogenic origin represent a major stressor to ecosystems, including human and wildlife populations.
Learn More
link
Seemingly Surreal Swallows in a Spring Snowstorm, by Keith Williams.

Biogeography: Stable Isotope Applications

The distribution of species across the landscape is of great interest to conservation biology. Habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences. However, for species with cryptic or migratory life histories, we often lack sufficient detail about habitat usage and in many cases...
By
Fort Collins Science Center
link

Biogeography: Stable Isotope Applications

The distribution of species across the landscape is of great interest to conservation biology. Habitat quality and quantity are thought to be important drivers of occurrence and distribution, and numerous studies have demonstrated fitness-related consequences. However, for species with cryptic or migratory life histories, we often lack sufficient detail about habitat usage and in many cases...
Learn More
link
Waterfall in Appalachian Forest

Biogeochemistry: Stable Isotope Applications

Biogeochemical cycling is a cornerstone of ecosystem function and structure. Much has been learned about element cycles in a variety of systems using standard geochemical techniques.
By
Fort Collins Science Center
link

Biogeochemistry: Stable Isotope Applications

Biogeochemical cycling is a cornerstone of ecosystem function and structure. Much has been learned about element cycles in a variety of systems using standard geochemical techniques.
Learn More
link
The sunset on the main city beach in Laguna Beach, CA.

Ecological Applications of Stable Isotopes

Environmental contaminants of natural and anthropogenic origin represent a major stressor to ecosystems, including human and wildlife populations. FORT scientists are studying these stressors in order to understand the contaminant cycling under natural environmental conditions. Stable isotope techniques are extremely useful in resolving trophic pathways by which contaminants become bioavailable...
By
Land Management Research Program, Fort Collins Science Center
link

Ecological Applications of Stable Isotopes

Environmental contaminants of natural and anthropogenic origin represent a major stressor to ecosystems, including human and wildlife populations. FORT scientists are studying these stressors in order to understand the contaminant cycling under natural environmental conditions. Stable isotope techniques are extremely useful in resolving trophic pathways by which contaminants become bioavailable...
Learn More
link
A polar bear in a pool.

Foraging Ecology Using Stable Isotopes

Understanding species habitat requirements is incomplete without insight into nutrition, including various aspects of foraging ecology. Traditional diet studies can be challenging because of logistics, issues related to resource availability, and observations are often short-term in nature based on gut contents or scat. Additionally, perturbations such as species introductions, habitat degradation...
By
Land Management Research Program, Species Management Research Program, Fort Collins Science Center
link

Foraging Ecology Using Stable Isotopes

Understanding species habitat requirements is incomplete without insight into nutrition, including various aspects of foraging ecology. Traditional diet studies can be challenging because of logistics, issues related to resource availability, and observations are often short-term in nature based on gut contents or scat. Additionally, perturbations such as species introductions, habitat degradation...
Learn More
Filter Total Items: 17

Geochemical Analyses of Water, Mine tailings, Fluvial Suspended Sediments, Fluvial Bed Sediments, and Fluvial Flood Deposit Sediments from the Big River and Meramec River Drainage Basins, Missouri

Geochemical data for aqueous, mine tailings, and sediment samples collected from the Big River and Meramec River drainage basins in southeastern Missouri are presented. The Big River drains historical lead, zinc, and barite mining districts, including the Old Lead Belt (OLB). Underground mining in the OLB resulted in large mine-waste chat piles and tailings impoundments that have released material
By
Central Midwest Water Science Center

Laboratory analyses for fish tissue from Lake Koocanusa and Kootenai River Basin, Montana, 2022

This data release includes laboratory analyses for fish tissue samples collected from Lake Koocanusa and the Kootenai River Basin in Montana during 2022. Samples were collected by the U.S. Geological Survey Wyoming-Montana Water Science Center in cooperation with Montana Fish, Wildlife and Parks and Montana Department of Environmental Quality. Analyses include histology, percent moisture, and 30 e
By
Wyoming-Montana Water Science Center

Silicified wood from around Old Faithful Geyser, Yellowstone National Park

Old Faithful Geyser in the Upper Geyser Basin of Yellowstone National Park is one of the best studied geysers in the world. Under research permit YELL-SCI-8030, samples from 13 silicified tree remnants were collected adjacent to the Old Faithful Geyser cone in April and November 2019. The silicified wood samples were dated using the radiocarbon (14C) method and were analyzed by scanning electron m
By
Volcano Science Center

Modeled Pacific salmon escapement biomass and nutrient and contaminant concentrations across western North America, 1976-2015

The data contain yearly modeled estimates of Pacific salmon escapement (in annual metric tons of wet mass) from 1976 to 2015 across four regions of western North America. A second data file contains modeled estimates of contaminant or nutrient concentrations in Pacific Salmon. The modeled estimates were derived from Bayesian generalized linear models (contaminant or nutrient concentrations) or fro
By
Columbia Environmental Research Center

Total mercury, methylmercury, and isotopic composition in various life stages of boreal chorus frogs (Pseudacris maculata) at two subalpine ponds in the Rocky Mountains, CO, USA, 2015

Mercury is an atmospherically transported contaminant found even in relatively pristine habitats. Once accumulated at the base of the food web, mercury can move between animals that are linked trophically. Pond-breeding amphibians may be particularly important vectors of mercury flux from remote freshwater to terrestrial systems because they feed on algae and detritus as tadpoles and metamorphose
By
Columbia Environmental Research Center

Mercury concentrations, isotopic composition, biomass, and taxonomy of stream and riparian organisms in the vicinity of Yellow Pine, Idaho, 2015-2016.

This data release includes sampling location data; field-collected stream attribute data; laboratory-analyzed chemistry concentrations (total mercury, methyl mercury) and isotopic composition (total mercury, carbon, and nitrogen) for stream biota (seston, periphyton, benthic insects, emerging adult insects, riparian spiders, and fish); density, body length, and taxonomic information for benthic in
By
Mineral Resources Program, Columbia Environmental Research Center, Geology, Geophysics, and Geochemistry Science Center

Dataset for temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river

The trace element selenium is an essential element with a narrow window between concentrations needed to support life and those that cause toxicity to egg laying organisms. Selenium bioaccumulation in aquatic organisms is primarily the result of trophic transfer through food webs and is poorly predicted by dissolved concentrations in freshwater bodies. To better understand the hydrologic and biolo
By
Wyoming-Montana Water Science Center

Chemistry of water, stream sediment, wildfire ash, soil, dust, and mine waste for Fourmile Creek Watershed, Colorado, 2010-2019

In response to the 2010 Fourmile Canyon fire near Boulder, Colorado, the U.S. Geological Survey collected data to support investigations into the magnitude and critical drivers of water-quality impairment after wildfire. We analyzed chemistry of stream water, sediment, wildfire ash, soil, dust, and mine waste for metals and other parameters in order to evaluate the effects of legacy mining and wil
By
Water Resources Mission Area

Radiogenic strontium isotope data for non-native walleye otoliths collected from select areas of the Upper Colorado River Basin

This dataset includes radiogenic strontium isotope compositions of non-native walleye otoliths collected from select areas of the Upper Colorado River Basin (UCRB). Strontium isotope data have been widely used to assess natal areas for a variety of fish species. Following on previous work, this project sought to fill data gaps for walleye collected from the Colorado River (river miles 11-109.3), t
By
Fort Collins Science Center

Stable carbon isotope and wood component concentration data for riparian cottonwood tree rings, Little Missouri River, North Dakota

This dataset includes stable carbon isotope values, lignin, cellulose, and hemicellulose concentrations (expressed as percent of ash-free dry mass) for riparian cottonwood (Populus deltoides) tree rings growing on the Little Missouri River floodplain, Theodore Roosevelt National Park, North Dakota. Drought stress induces stomatal closure and the carbon isotope ratio of annual tree rings tends to
By
Fort Collins Science Center

Stable carbon and nitrogen isotope data for Siberian barn swallow subspecies collected during the breeding season

This dataset includes stable carbon and nitrogen isotope values for the inner tail retrices of three subspecies of barn swallow (Hirundo rustica rustica, H. r. tytleri, and H. r. gutturalis). Sampling was conducted in Russia (summer 2013), China (summer 2014), Mongolia (summer 2014), Japan (summer 2014), and western China (summer 2015) using mist nets. Stable carbon and nitrogen isotope data are u
By
Fort Collins Science Center

Ovary mass and stable hydrogen isotope data for resident and migratory female dark-eyed juncos

This dataset includes ovary mass and stable hydrogen isotope compositions of feathers and claws from resident and migratory female dark-eyed juncos (Junco hyemalis) collected during early spring at Mountain Lake Biological Station, Pembroke, Virginia. A total of 18 migrant and 15 resident female dark-eyed juncos, a songbird that exhibits seasonal sympatry, were caught during March-April. Stable hy
By
Fort Collins Science Center
No results found.
Filter Total Items: 81

Design, development, and implementation of IsoBank: A centralized repository for isotopic data

Stable isotope data have made pivotal contributions to nearly every discipline of the physical and natural sciences. As the generation and application of stable isotope data continues to grow exponentially, so does the need for a unifying data repository to improve accessibility and promote collaborative engagement. This paper provides an overview of the design, development, and implementation of
Authors
Oliver N. Shipley, Anna J. Dabrowski, Gabriel J. Bowen, Brian Hayden, Jonathan N. Pauli, Christopher Jordan, Lesleigh Anderson, Adriana Bailey, Clement P. Bataille, Carla Cicero, Hilary G. Close, Craig Cook, Joseph A. Cook, Ankur R. Desai, Jaivime Evaristo, Tim R. Filley, Christine A.M. France, Sora Lee Kim, Sebastian H. Kopf, Julie Loisel, Philip J. Manlick, Jamie M. McFarlin, Bailey C. McMeans, Tamsin C. O'Connel, Brice X. Semmens, Chris Stantis, Paul Szejner, Suzanne E. Pilaar Birch, Annie L. Putman, Craig A. Stricker, Tara L.E. Trammell, Mark D. Uhen, Samantha Weintraub-Leff, Matthew J. Wooller, John W. Williams, Christopher T. Yarnes, Hanna B. Vander Zanden, Seth D. Newsome
By
Ecosystems Mission Area, Water Resources Mission Area, Fort Collins Science Center, Utah Water Science Center

Geographic distribution of feather δ34S in Europe

Geographic distribution models of environmentally stable isotopes (the so-called “isoscapes”) are widely employed in animal ecology, and wildlife forensics and conservation. However, the application of isoscapes is limited to elements and regions for which the spatial patterns have been estimated. Here, we focused on the ubiquitous yet less commonly used stable sulfur isotopes (δ34S). To predict t
Authors
Vojtěch Brlík, Petr Procházka, Luana Bontempo, Federica Camin, Frédéric Jiguet, Gergely Osváth, Craig A. Stricker, Michael B. Wunder, Rebecca L. Powell
By
Ecosystems Mission Area, Fort Collins Science Center

Complex life histories alter patterns of mercury exposure and accumulation in a pond-breeding amphibian

Quantifying how contaminants change across life cycles of species that undergo metamorphosis is critical to assessing organismal risk, particularly for consumers. Pond-breeding amphibians can dominate aquatic animal biomass as larvae and are terrestrial prey as juveniles and adults. Thus, amphibians can be vectors of mercury exposure in both aquatic and terrestrial food webs. However, it is still
Authors
Freya Elizabeth Rowland, Erin L. Muths, Collin A. Eagles-Smith, Craig A. Stricker, Johanna M. Kraus, Rachel A. Harrington, David Walters
By
Ecosystems Mission Area, Columbia Environmental Research Center, Fort Collins Science Center

Animal tracing with sulfur isotopes: Spatial segregation and climate variability in Africa likely contribute to population trends of a migratory songbird

Climatic conditions affect animals but range-wide impacts at the population level remain largely unknown, especially in migratory species. However, studying climate–population relationships is still challenging in small migrants due to a lack of efficient and cost-effective geographic tracking method.Spatial distribution patterns of environmental stable isotopes (so called ‘isoscapes’) generally o
Authors
Vojtech Brlik, Petr Prochazka, Bengt Hansson, Craig A. Stricker, Elizabeth Yohannes, Rebecca L Powell, Michael B. Wunder
By
Ecosystems Mission Area, Fort Collins Science Center

Diet energy density estimated from isotopes in predator hair associated with survival, habitat, and population dynamics

Sea ice loss is fundamentally altering the Arctic marine environment. Yet there is a paucity of data on the adaptability of food webs to ecosystem change, including predator-prey interactions. Polar bears (Ursus maritimus) are an important subsistence resource for Indigenous people and an apex predator that relies entirely on the under-ice food web to meet their energy needs. Here, we assessed whe
Authors
Karyn D. Rode, Brian D. Taras, Craig A. Stricker, Todd C. Atwood, Nicole P Boucher, George M. Durner, Andrew E. Derocher, Evan S. Richardson, Seth Cherry, Lori T. Quakenbush, Lara Horstmann, Jeffrey F. Bromaghin
By
Ecosystems Mission Area, Alaska Science Center, Fort Collins Science Center

Summer/fall diet and macronutrient assimilation in an Arctic predator

Free-ranging predator diet estimation is commonly achieved by applying molecular-based tracers because direct observation is not logistically feasible or robust. However, tracers typically do not represent all dietary macronutrients, which likely obscures resource use as prey proximate composition varies and tissue consumption can be specific. For example, polar bears (Ursus maritimus) preferentia
Authors
Craig A. Stricker, Karyn D. Rode, Brian D. Taras, Jeffrey F. Bromaghin, Lara Horstmann, Lori T. Quakenbush
By
Ecosystems Mission Area, Alaska Science Center, Fort Collins Science Center

Increased mercury and reduced insect diversity in linked stream-riparian food webs downstream of a historical mercury mine

Historical mining left a legacy of abandoned mines and waste rock in remote headwaters of major river systems in the western United States. Understanding the influence of these legacy mines on culturally and ecological important downstream ecosystems is not always straight-forward because of elevated natural levels of mineralization in mining-impacted watersheds. To test the ecological effects of
Authors
Johanna M. Kraus, JoAnn Holloway, Michael Pribil, Ben N. Mcgee, Craig A. Stricker, Danny Rutherford, Andrew S. Todd
By
Ecosystems Mission Area, Columbia Environmental Research Center

The reuse of avian samples: Opportunities, pitfalls and a solution

Tissue samples are frequently collected to study various aspects of avian biology, but in many cases these samples are not used in their entirety and are stored by the collector. The already collected samples provide a largely overlooked opportunity because they can be used by different researchers in different biological fields. Broad reuse of samples could result in multispecies or large-scale s
Authors
Vojtěch Brlík, Pavel Pipek, Kate Brandis, Nikita Chernetsov, Fábio J. V. Costa, L. Gerardo Herrera M., Yosef Kiat, Richard B. Lanctot, Peter P. Marra, D. Ryan Norris, Chima J. Nwaogu, Petra Quillfeldt, Sarah T. Saalfeld, Craig A. Stricker, Robert L. Thomson, Tianhao Zhao, Petr Procházka
By
Ecosystems Mission Area, Fort Collins Science Center

Energetic and health effects of protein overconsumption constrain dietary adaptation in an apex predator

Studies of predator feeding ecology commonly focus on energy intake. However, captive predators have been documented to selectively feed to optimize macronutrient intake. As many apex predators experience environmental changes that affect prey availability, limitations on selective feeding can affect energetics and health. We estimated the protein:fat ratio of diets consumed by wild polar bears us
Authors
Karyn D. Rode, Charles T. Robbins, Craig A. Stricker, Brian D. Taras, Troy N Tollefson
By
Ecosystems Mission Area, Alaska Science Center, Fort Collins Science Center

Temporal influences on selenium partitioning, trophic transfer, and exposure in a major U.S. river

Hydrologic and irrigation regimes mediate the timing of selenium (Se) mobilization to rivers, but the extent to which patterns in Se uptake and trophic transfer through recipient food webs reflect the temporal variation in Se delivery is unknown. We investigated Se mobilization, partitioning, and trophic transfer along approximately 60 river miles of the selenium-impaired segment of the Lower Gunn
Authors
Jessica E Brandt, James Roberts, Craig A. Stricker, Holly Rogers, Patricia Nease, Travis S. Schmidt
By
Ecosystems Mission Area, Water Resources Mission Area, Fort Collins Science Center, Great Lakes Science Center, Wyoming-Montana Water Science Center

Breeding at higher latitude is associated with higher photoperiodic threshold and delayed reproductive development in a songbird

Many seasonally breeding animals exhibit a threshold day length (critical photoperiod; CPP) for gonadal growth, and populations breeding at higher latitudes typically have a higher CPP. Much less is known about latitudinal variation in CPP in migratory population that winter away from their breeding range and must time their reproduction to match favorable conditions at their destination. To addre
Authors
Devraj Singh, S. M. Reed, A. A. Kimmitt, K. A. Alford, Craig A. Stricker, P. D. Polly, Ellen D. Ketterson
By
Ecosystems Mission Area, Fort Collins Science Center

Evidence of post-breeding prospecting in a long-distance migrant.

Organisms assess biotic and abiotic cues at multiple sites when deciding where to settle. However, due to temporal constraints on this prospecting, the suitability of available habitat may be difficult for an individual to assess when cues are most reliable, or at the time they are making settlement decisions. For migratory birds, the postbreeding season may be the optimal time to prospect and inf
Authors
Max Ciaglo, Ross Calhoun, Scott W Yanco, Michael B. Wunder, Craig A. Stricker, Brian D Linkhart
By
Ecosystems Mission Area, Fort Collins Science Center

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.

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