Skip to main content

Person

Robert K Al-Chokhachy

Research Fishery Biologist

Northern Rocky Mountain Science Center

Email: ral-chokhachy@usgs.gov
Office Phone: 406-994-7842
Fax: 406-994-6556
ORCID: 0000-0002-2136-5098

Location
The Transportation and Systems
2327 University Way
Suite 2
Bozeman , MT 59715
US

Supervisor: Clint C Muhlfeld
thumbnail
We collected diets on Yellowstone cutthroat trout (Oncorhynchus clarkii bouvieri) and brown trout (Salmo trutta) above (Yellowstone cutthroat trout allopatry) and below (Yellowstone cutthroat trout sympatry with brown trout) a natural barrier in Duck Creek, Montana. We used gastric lavage methods to collect diets, and samples were placed in storage containers and taken back to our lab and frozen until sorting. All samples were sorted by Rhithron, Inc. (Missoula, MT) with individuals identified down to the order.
Field estimates of the abundance of rainbow trout in Washington and British Columbia were collected in concert with environmental DNA samples (eDNA) to evaluate if eDNA copy numbers correlated with abundance of trout. In addition, stream habitat data including channel units (pools, riffles), substrate, large woody debris, among others, were collected at sites.
Climate change may facilitate the expansion of non-native invasive species (NIS) in aquatic and terrestrial systems. However, empirical evidence remains scarce and poorly synthesized at scales necessary for effective management. We conducted a literature synthesis to assess the state of research on the observed and predicted effects of climate change on a suite of 398 aquatic and terrestrial NIS now present in or a major threat to aquatic and terrestrial ecosystems of the Pacific Northwest (PNW), USA and British Columbia. Surprisingly, very few studies (n = 15) have investigated the observed effects of climate change on the distribution, abundance, spread, or impact of the focal NIS, with only five studies focusing...
Field estimates of the abundance of two trout species (bull trout and westslope cutthroat trout) in Montana and rainbow trout in Washington and British Columbia were collected in concert with environmental DNA samples (eDNA) to evaluate if eDNA copy numbers correlated with abundance of trout. In addition, stream habitat data including channel units (pools, riffles), substrate, large woody debris, among others, were collected at sites.
The dataset includes measurements of stream habitat, fish abundance of westslope cutthroat trout and bull trout, and species-specific measures of environmental DNA (eDNA) from within the water. The data covers multiple streams in western Montana.
View more...
ScienceBase brings together the best information it can find about USGS researchers and offices to show connections to publications, projects, and data. We are still working to improve this process and information is by no means complete. If you don't see everything you know is associated with you, a colleague, or your office, please be patient while we work to connect the dots. Feel free to contact sciencebase@usgs.gov.