Isaak, D.J., C.C. Muhlfeld, A.S. Todd, R. Al-Chokhatchy, J.J. Roberts, K.D. Fausch, J.L. Kershner, and S.W. Hostetler. 2012 The past as prelude to the future: Retrospective assessments for anticipating future climate vulnerabilities of salmonid fishes in the Rocky Mountain West. Fisheries 37(12): 542-556.
James J Roberts
Biography
James has broad research expertise and investigates the ecological consequences of environmental stressors like climate change and eutrohpication for aquatic systems and specifically fish populations. Currently, he is investigating the potential effects climate change may have on the persistance of Colorado River cutthroat trout (Oncorhynchus clarkii pleuriticus) in stream and lake habitats throughout the Upper Colorado River basin. He has also conducted research in the Laurentian Great Lakes examining the ecological consequences of seasonal hypolimnetic hypoxia, dead zones, in Lake Erie. Specifically, he investigated the effects (behavioral, physiological,and inter-specific) of hypoxia on the benthic fish assemblage of Lake Erie, while focusing on yellow perch.
Science and Products
Date published: August 29, 2016
Ecological Responses to Fish Reclamation Treatments
Piscicides have been used in Rocky Mountain stream and lakes to restore native fish populations. In the last two decades concerns over piscicide effects to non-target organisms, primarily aquatic invertebrates, has increased. Although piscicides have been used for more than 70 years the impact to invertebrate assemblages has not been well studied and is largely unknown. Given the importance a...
Date published: July 5, 2016
Status: Active Climate Change and Trout
Cold-water fishes like trout, salmon, and charr are especially vulnerable to shifting conditions related to climate change; for example, warmer temperatures and more variable hydroclimate. Native cutthroat trout of the southern Rocky Mountains now only occupy a tiny fraction of their historic habitats because of stressors such as non-native fishes, habitat fragmentation, and detrimental land...
Date published: January 1, 2016
Status: Active Characterization of Water Quality and Biology in the Fountain Creek Watershed
Monument and Fountain Creeks and their respective watersheds, located in the Front Range of Colorado, serve as important drainages for surface runoff, waste-water treatment operations, and as a water supply for downstream agricultural needs. As population growth continues in these watersheds, more and more pressures are being applied to the receiving streams, especially Fountain Creek. ...
Contacts: Robert E Zuellig, Ph.D., James J Roberts
Attribution: Region 7: Upper Colorado Basin, Colorado Water Science Center
Date published: October 30, 2020
Invertebrate community data from native trout lakes and streams in the Southern Rocky Mountains
Native trout in the West suffer a high degree of vulnerability, as highlighted by cutthroat trout, a group of 14 subspecies, most of which have been petitioned for listing under the Endangered Species Act (ESA). In the Southern Rocky Mountains, greenback cutthroat trout (Oncorhynchus clarkii stomias; GBCT) are listed as threatened under the ESA, and few populations remain, i
Attribution: Colorado Water Science Center
Year Published: 2020
Mercury and selenium concentrations in fishes of the Upper Colorado River Basin, southwestern United States: A retrospective assessment
Mercury (Hg) and selenium (Se) are contaminants of concern for fish in the Upper Colorado River Basin (UCRB). We explored Hg and Se in fish tissues (2,324 individuals) collected over 50 years (1962–2011) from the UCRB. Samples include native and non-native fish collected from lotic waterbodies spanning 7 major tributaries to the Colorado River....
Day, Natalie K.; Schmidt, Travis; Roberts, James J.; Osmundson, Barbara C.; Willacker, James; Eagles-Smith, Collin
Year Published: 2019
Predicting persistence of Rio Grande Cutthroat Trout populations in an uncertain future
The Rio Grande Cutthroat Trout Oncorhynchus clarkii virginalis (RGCT ) occupies just 12% of its ancestral range. As the southernmost subspecies of Cutthroat Trout, we expect a warming climate to bring additional stressors to RGCT populations, such as increased stream temperatures, reduced streamflows, and increased incidence of wildfire...
Zeigler, Mathew P.; Rogers, Kevin B.; Roberts, James J.; Todd, Andrew; Fausch, Kurt D.Attribution: Fort Collins Science Center, Ecosystems
Year Published: 2019
Estimating lake–climate responses from sparse data: An application to high elevation lakes
Although many studies demonstrate lake warming, few document trends from lakes with sparse data. Diel and seasonal variability of surface temperatures limit conventional trend analyses to datasets with frequent repeated observations. Thus, remote lakes, including many high elevation lakes, are underrepresented in trend analyses. We used a Bayesian...
Christianson, Kyle R.; Johnson, Brett M.; Hooten, Mevin; Roberts, James J.
Year Published: 2018
Comparability among four invertebrate sampling methods and two multimetric indexes, Fountain Creek Basin, Colorado, 2010–2012
The U.S. Geological Survey (USGS), in cooperation with Colorado Springs City Engineering and Colorado Springs Utilities, analyzed previously collected invertebrate data to determine the comparability among four sampling methods and two versions (2010 and 2017) of the Colorado Benthic Macroinvertebrate Multimetric Index (MMI). For this study,...
Bruce, James F.; Roberts, James J.; Zuellig, Robert E.Attribution: Water, Colorado Water Science Center, Water Resources, Region 7: Upper Colorado Basin, Colorado, United States of America
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Bruce, J.F., Roberts, J.J., and Zuellig, R.E., 2018, Comparability among four invertebrate sampling methods and two multimetric indexes, Fountain Creek Basin, Colorado, 2010–2012: U.S. Geological Survey Scientific Investigations
Report 2018–5061, 11 p., https://doi.org/10.3133/sir20185061.
Year Published: 2018
Changes in biological communities of the Fountain Creek Basin, Colorado, 2003–2016, in relation to antecedent streamflow, water quality, and habitat
The analysis described in this report is part of a longterm project monitoring the biological communities, habitat, and water quality of the Fountain Creek Basin. Biology, habitat, and water-quality data have been collected at 10 sites since 2003. These data include annual samples of aquatic invertebrate communities, fish communities, water...
Roberts, James J.; Bruce, James F.; Zuellig, Robert E.Attribution: Water, Colorado Water Science Center, Water Resources, Region 7: Upper Colorado Basin, Colorado, United States of America
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Roberts, J.J., Bruce, J.F., and Zuellig, R.E., 2018, Changes in biological communities of the Fountain Creek Basin, Colorado, 2003–2016, in relation to antecedent streamflow, water quality, and habitat: U.S. Geological Survey Scientific Investigations Report 2017–5162, 20 p., https://doi.org/10.3133/sir20175162.
Year Published: 2017
Thermal regimes of Rocky Mountain lakes warm with climate change
Anthropogenic climate change is causing a wide range of stresses in aquatic ecosystems, primarily through warming thermal conditions. Lakes, in response to these changes, are experiencing increases in both summer temperatures and ice-free days. We used continuous records of lake surface temperature and air temperature to create statistical models...
Roberts, James J.; Fausch, Kurt D.; Schmidt, Travis S.; Walters, David M.Attribution: Colorado Water Science Center, Water Resources, Climate Research and Development Program, Land Change Science Program, Region 7: Upper Colorado Basin, United States of America
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Roberts JJ, Fausch KD, Schmidt TS, Walters DM (2017) Thermal regimes of Rocky Mountain lakes warm with climate change. PLoS ONE 12(7): e0179498. https://doi.org/10.1371/journal.pone.0179498
Year Published: 2017
Effects of internal phosphorus loadings and food-web structure on the recovery of a deep lake from eutrophication
We used monitoring data from Lake Lugano (Switzerland and Italy) to assess key ecosystem responses to three decades of nutrient management (1983–2014). We investigated whether reductions in external phosphorus loadings (Lext) caused declines in lake phosphorus concentrations (P) and phytoplankton biomass (Chl a), as assumed by the predictive...
Lepori, Fabio; Roberts, James J.View Citation
Lepori, F., Roberts, J.J., 2017, Effects of internal phosphorus loadings and food-web structure on the recovery of a deep lake from eutrophication: Journal of Great Lakes Research, v. 43, issue 2, p. 255-264, http://dx.doi.org/10.1016/j.jglr.2017.01.008
Year Published: 2017
Nonnative trout invasions combined with climate change threaten persistence of isolated cutthroat trout populations in the southern Rocky Mountains
Effective conservation of Cutthroat Trout Oncorhynchus clarkii lineages native to the Rocky Mountains will require estimating effects of multiple stressors and directing management toward the most important ones. Recent analyses have focused on the direct and indirect effects of a changing climate on contemporary ranges, which are much reduced...
Roberts, James J.; Kurt D. Fausch; Hooten, Mevin; Peterson, Douglas P.Attribution: Fort Collins Science Center, Colorado Water Science Center, Water Resources, Ecosystems, Region 7: Upper Colorado Basin, United States of America
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Roberts, J.J., Fausch, K.D., Hooten, M.B., and Peterson, D.P., 2017, Nonnative trout invasions combined with climate change threaten persistence of isolated Cutthroat Trout populations in the southern Rocky Mountains: North American Journal of Fisheries Management, v. 37, issue 2, p. 314-325, http://dx.doi.org/10.1080/02755947.2016.1264507
Year Published: 2015
Past and future warming of a deep European lake (Lake Lugano): What are the climatic drivers?
We used four decades (1972–2013) of temperature data from Lake Lugano, Switzerland and Italy, to address the hypotheses that: [i] the lake has been warming; [ii] part of the warming reflects global trends and is independent from climatic oscillations and [iii] the lake will continue to warm until the end of the 21st century. During the time...
Lepori, Fabio; Roberts, James J.Attribution: Fort Collins Science Center, Ecosystems
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Lepori, F., Roberts, J.J., Past and future warming of a deep European lake (Lake Lugano): What are the climatic drivers?, J. Great Lakes Res. 41 (2015) 973-981
Year Published: 2014
Assessing and addressing the re-eutrophication of Lake Erie: central basin hypoxia
Relieving phosphorus loading is a key management tool for controlling Lake Erie eutrophication. During the 1960s and 1970s, increased phosphorus inputs degraded water quality and reduced central basin hypolimnetic oxygen levels which, in turn, eliminated thermal habitat vital to cold-water organisms and contributed to the extirpation of important...
Scavia, Donald; Allan, J. David; Arend, Kristin K.; Bartell, Steven; Beletsky, Dmitry; Bosch, Nate S.; Brandt, Stephen B.; Briland, Ruth D.; Daloğlu, Irem; DePinto, Joseph V.; Dolan, David M.; Evans, Mary Anne; Farmer, Troy M.; Goto, Daisuke; Han, Haejin; Höök, Tomas O.; Knight, Roger; Ludsin, Stuart A.; Mason, Doran; Michalak, Anna M.; Richards, R. Peter; Roberts, James J.; Rucinski, Daniel K.; Rutherford, Edward; Schwab, David J.; Sesterhenn, Timothy M.; Zhang, Hongyan; Zhou, YuntaoAttribution: Great Lakes Science Center, Ecosystems
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Assessing and addressing the re-eutrophication of Lake Erie: central basin hypoxia; 2014; Article; Journal; Journal of Great Lakes Research; Scavia, Donald; Allan, J. David; Arend, Kristin K.; Bartell, Steven; Beletsky, Dmitry; Bosch, Nate S.; Brandt, Stephen B.; Briland, Ruth D.; Daloğlu, Irem; DePinto, Joseph V.; Dolan, David M.; Evans, Mary Anne; Farmer, Troy M.; Goto, Daisuke; Han, Haejin; Höök, Tomas O.; Knight, Roger; Ludsin, Stuart A.; Mason, Doran; Michalak, Anna M.; Richards, R. Peter; Roberts, James J.; Rucinski, Daniel K.; Rutherford, Edward; Schwab, David J.; Sesterhenn, Timothy M.; Zhang, Hongyan; Zhou, Yuntao
Year Published: 2013
Fragmentation and thermal risks from climate change interact to affect persistence of native trout in the Colorado River basin
Impending changes in climate will interact with other stressors to threaten aquatic ecosystems and their biota. Native Colorado River cutthroat trout (CRCT; Oncorhynchus clarkii pleuriticus) are now relegated to 309 isolated high-elevation (>1700 m) headwater stream fragments in the Upper Colorado River Basin, owing to past nonnative trout...
Roberts, James J.; Fausch, Kurt D.; Peterson, Douglas P.; Hooten, MevinView Citation
Fragmentation and thermal risks from climate change interact to affect persistence of native trout in the Colorado River basin; 2013; Article; Journal; Global Change Biology; Roberts, James J.; Fausch, Kurt D.; Peterson, Douglas P.; Hooten, Mevin B.
Year Published: 2012
The past as prelude to the future for understanding 21st-century climate effects on Rocky Mountain Trout
Bioclimatic models predict large reductions in native trout across the Rocky Mountains in the 21st century but lack details about how changes will occur. Through five case histories across the region, we explore how a changing climate has been affecting streams and the potential consequences for trout. Monitoring records show trends in temperature...
Isaak, Daniel J.; Muhlfeld, Clint C.; Todd, Andrew S.; Al-chokhachy, Robert; Roberts, James; Kershner, Jeffrey L.; Fausch, Kurt D.; Hostetler, Steven W.Attribution: Northern Rocky Mountain Science Center, , Geology, Minerals, Energy, and Geophysics Science Center, Geology, Geophysics, and Geochemistry Science Center, Ecosystems, , Region 7: Upper Colorado Basin
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The past as prelude to the future for understanding 21st-century climate effects on Rocky Mountain Trout; 2012; Article; Journal; Fisheries; Isaak, Daniel J.; Muhlfeld, Clint C.; Todd, Andrew S.; Al-chokhachy, Robert; Roberts, James; Kershner, Jeffrey L.; Fausch, Kurt D.; Hostetler, Steven W.
Pre-USGS Publications
Goto, D., K. Lindelof, D.L. Fanslow, S.A. Ludsin, J.J. Roberts, H.A. Vanderploeg, A.F. Wilson, and T.O. Höök. 2012. Indirect consequences of hypolimnetic hypoxia on
zooplankton growth in a large eutrophic lake. Aquatic Biology 16: 217-227.
Roberts, J.J., P.A. Grecay, S.A. Ludsin, S.A. Pothoven, H.A. Vanderploeg, and T.O. Höök. 2012 Evidence of hypoxic foraging forays by yellow perch (Perca flavescens) and potential consequences for prey consumption. Freshwater Biology 57: 922-937.
Roberts, J.J., T.O. Hook, S.A. Ludsin, S.A. Pothoven, H.A. Vanderploeg, and S.B. Brandt. 2009. Effects of hypolimnetic hypoxia in Lake Erie's central basin on foraging and distribution of yellow perch. Journal of Experimental Marine Biology and Ecology. 131:S132-S142.
Roberts, J.J. and F.J. Rahel. 2008. Irrigation canals as sink habitat for trout and other fishes in a Wyoming drainage. Transactions of the American Fisheries Society. 137:951-961.
Roberts, J.J. and F.J. Rahel. 2005. Accuracy of aerial telemetry in fisheries studies. North American Journal of Fisheries Management. 25:660-666.
Roberts, J.J. 2010. The ecological consequences of hypoxia for yellow perch (Perca flavescens) in Lake Erie. Doctoral Dissertation. 181 pp.