Barry Arm of Harriman Fjord, Prince William Sound, Alaska. Included is Barry Glacier and Cascade Glacier.
Christian E Zimmerman, Ph.D.
Actionable science to inform decision makers, managers, and the public
Professional Experience
2017 - Present Center Director, USGS Alaska Science Center, Anchorage, Alaska
2015 - 2017 Chief, Water and Interdisciplinary Studies Office, USGS, Alaska Science Center, Anchorage, Alaska
2002 - Present Chair Scientific and Technical Committee, Arctic-Yukon-Kuskokwim Sustainable Salmon Initiative, Anchorage, Alaska
2001-2015 Research Fish Biologist, Alaska Science Center, Anchorage, AK
2000 - 2001 Scientist, University of Washington, Seattle, Washington
1995 - 1997 Fishery Biologist, U.S. Forest Service Pacific Northwest Research Station, Corvallis, Oregon
1993 - 1995 Graduate Research Assistant, Oregon State University, Corvallis, Oregon
1992 Fishery Biologist, Thomas R. Payne and Associates/Pacific Land and Water Resources Consultants, Arcata, California
1991 Teaching Assistant, Humboldt State University, Arcata, California
1990 - 1991 Research Assistant, Institute of Limnology, Uppsala University, Uppsala, Sweden
1989 - 1990 Biological Technician, Redwood National Park, Arcata, California
Education and Certifications
Ph.D. 2000 Oregon State University, Corvallis, OR Fishery Science
M.S. 1996 Oregon State University, Corvallis, OR Fishery Science
B.S. 1992 Humboldt State University, Arcata, CA Fishery Biology
Science and Products
Hydro-Ecology of Arctic Thawing (HEAT): Hydrology
Science Support Program and Quick Response Program
Assessing heat stress in migrating Yukon River Chinook Salmon
The Rusting of Arctic Rivers: Freshwater Ecosystems Respond to Rapidly Uptaking Metals
Outer Continental Shelf Program
Collaborative Science for Priority Information Needs
Natural Resources Preservation Program
Arctic Lake Food Webs
Ecosystem Shifts in Arctic Seas
Lake Trout Biochronologies as Long-term Climate and Productivity Indicators in Alaska Lake Ecosystems
Primary Production Sources and Bottom-up Limitations in Nearshore Ecosystems
Hydro-Ecology of Arctic Thawing (HEAT): Ecology
Barry Arm of Harriman Fjord, Prince William Sound, Alaska. Included is Barry Glacier and Cascade Glacier.
Contents of the fyke net that was set in the lake near Atqasuk in 2016. All sticklebacks.
Contents of the fyke net that was set in the lake near Atqasuk in 2016. All sticklebacks.
Collecting water quality data on the Pilgrim River. Types of measurements taken were on water temperature, dissolved oxygen, pH, and conductivity.
Collecting water quality data on the Pilgrim River. Types of measurements taken were on water temperature, dissolved oxygen, pH, and conductivity.
Randy Brown and Dan Young are setting nets to catch whitefish on Whitefish Lake in the Lake Clark National Park and Preserve.
Randy Brown and Dan Young are setting nets to catch whitefish on Whitefish Lake in the Lake Clark National Park and Preserve.
Kijik Lake in Lake Clark National Park and Preserve, Alaska. USGS researchers study salmon ecology in cooperation with NPS.
Kijik Lake in Lake Clark National Park and Preserve, Alaska. USGS researchers study salmon ecology in cooperation with NPS.
Reflections of Tanalian Mountain and Hardenburg Bay in Lake Clark, Alaska. Near Port Alsworth.
Reflections of Tanalian Mountain and Hardenburg Bay in Lake Clark, Alaska. Near Port Alsworth.
As part of the Changing Arctic Ecosystem project, two biologists sampling invertebrates near the Chipp River area.
As part of the Changing Arctic Ecosystem project, two biologists sampling invertebrates near the Chipp River area.
Ice wedge polygons near the Chipp River area on the north slope of Alaska
Ice wedge polygons near the Chipp River area on the north slope of Alaska
An enhanced photo of camp on the north slope.
A clear Montana Bill Creek flowing into volcanically silted creek. Coho salmon are seen holding in the clear water area. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
A clear Montana Bill Creek flowing into volcanically silted creek. Coho salmon are seen holding in the clear water area. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Cannery Creek on the west side of Cook Inlet, Alaska. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Cannery Creek on the west side of Cook Inlet, Alaska. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
A coho salmon holding in Montana Bill Creek after the Redoubt volcano eruption.
A coho salmon holding in Montana Bill Creek after the Redoubt volcano eruption.
A panorama of the Redoubt Volcano after the 2009 eruption and the Drift River delta in the foreground
A panorama of the Redoubt Volcano after the 2009 eruption and the Drift River delta in the foreground
Lower Drift River with tremendous amount of silt from the lahars. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Lower Drift River with tremendous amount of silt from the lahars. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Drift River on the west side of Cook Inlet, Alaska. Lahars from the eruption of Redoubt are evident. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Drift River on the west side of Cook Inlet, Alaska. Lahars from the eruption of Redoubt are evident. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Drift River on the west side of Cook Inlet, Alaska. Lahars from the eruption of Redoubt are evident. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams. Alaska Department of Fish and Game had done surveys in this particular area and found coho salmon before the eruption.
Drift River on the west side of Cook Inlet, Alaska. Lahars from the eruption of Redoubt are evident. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams. Alaska Department of Fish and Game had done surveys in this particular area and found coho salmon before the eruption.
View of the amount of lahar deposit from across the river and the amount of deposit the river has eroded out to sea in about 6 months. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
View of the amount of lahar deposit from across the river and the amount of deposit the river has eroded out to sea in about 6 months. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Aerial views of Tuxedni Bay on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial views of Tuxedni Bay on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial views of Tuxedni Bay on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial views of Tuxedni Bay on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial views of streams on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial views of streams on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Differential heat shock protein responses in two species of Pacific salmon and their utility in identifying heat stress
Elodea mediates juvenile salmon growth by altering physical structure in freshwater habitats
Investigating effects of climate-induced changes in water temperature and diet on mercury concentrations in an Arctic freshwater forage fish
Fish ear stones offer climate change clues in Alaska's lakes
First juvenile Chum Salmon confirms successful reproduction for Pacific salmon in the North American Arctic
Premature mortality observations among Alaska’s Pacific salmon during record heat and drought in 2019
Circumpolar patterns of Arctic freshwater fish biodiversity: A baseline for monitoring
Diversity of diatoms, benthic macroinvertebrates, and fish varies in response to different environmental correlates in Arctic rivers across North America
Migration strategies supporting salmonids in Arctic Rivers: A case study of Arctic Cisco and Dolly Varden
The distribution of anadromy in steelhead / rainbow trout in the Eel River, northwestern California
Egg retention of high-latitude sockeye salmon (Oncorhynchus nerka) in the Pilgrim River, Alaska, during the Pacific marine heatwave of 2014–2016
USGS permafrost research determines the risks of permafrost thaw to biologic and hydrologic resources
Science and Products
- Science
Filter Total Items: 15
Hydro-Ecology of Arctic Thawing (HEAT): Hydrology
The Arctic is warming at higher rates than much of the rest of the world. For Alaska, this results in changes in hydrology and ecosystems – permafrost is thawing, changing landscapes and releasing nutrients to soils and streams.Science Support Program and Quick Response Program
This is a nation-wide collaborative program, supported by the USGS Ecosystems Mission Area, through which USGS and U.S. Fish and Wildlife Service staff address priority research needs identified by the U.S. Fish and Wildlife Service. On this page, we highlight research taking place in Alaska as part of this program.Assessing heat stress in migrating Yukon River Chinook Salmon
We will examine evidence of heat stress in Yukon River Chinook salmon ( Oncorhynchus tshawytscha ) using heat shock proteins and gene expression.The Rusting of Arctic Rivers: Freshwater Ecosystems Respond to Rapidly Uptaking Metals
The water quality of streams and rivers in the Arctic is sensitive to rapid climate change and altered disturbance regimes.Outer Continental Shelf Program
This is a nation-wide collaborative program, supported by the USGS Ecosystems Mission Area, through which USGS and Bureau of Ocean Energy Management staff address priority research needs identified by the Bureau of Ocean Energy Management. On this page, we highlight research taking place in Alaska as part of this program.Collaborative Science for Priority Information Needs
One of the primary missions of the USGS is to address the science needs of Department of Interior bureaus, particularly those that manage natural resources and lands. This mission is fulfilled through the research and other activities of USGS scientists but also specifically through three USGS nationally-funded programs listed below.Natural Resources Preservation Program
This is a nation-wide collaborative program, supported by the USGS Ecosystems Mission Area, through which USGS and National Park Service staff address priority research needs identified by the National Park Service. On this page, we highlight research taking place in Alaska as part of this program.Arctic Lake Food Webs
From 2011 to 2013 we investigated freshwater food webs of Arctic Coastal Plain lakes in Alaska to improve our understanding how Arctic freshwater food webs may respond to landscape change the warmer, drier future.Ecosystem Shifts in Arctic Seas
In addition to the direct effects of sea ice loss on walrus ( Odobenus rosmarus divergens ) and polar bears ( Ursus maritimus ) that use ice as a platform, the decline of Arctic sea ice is predicted to promote a fundamental ecosystem shift from benthic animals that forage on the sea floor to pelagic animals that forage near the sea surface.Lake Trout Biochronologies as Long-term Climate and Productivity Indicators in Alaska Lake Ecosystems
High latitude ecosystems are among the most vulnerable to long-term climate change, yet continuous, multidecadal indicators by which to gauge effects on biology are scarce, especially in freshwater environments.Primary Production Sources and Bottom-up Limitations in Nearshore Ecosystems
Kelp forests are among the world’s most productive habitats, but recent evidence suggests that production is highly variable.Hydro-Ecology of Arctic Thawing (HEAT): Ecology
Permafrost thaw is leading to a myriad of changes in physical and chemical conditions throughout the Arctic. - Multimedia
Filter Total Items: 65Barry Arm of Harriman Fjord, Prince William Sound, AlaskaBarry Arm of Harriman Fjord, Prince William Sound, Alaska
Barry Arm of Harriman Fjord, Prince William Sound, Alaska. Included is Barry Glacier and Cascade Glacier.
Barry Arm of Harriman Fjord, Prince William Sound, Alaska. Included is Barry Glacier and Cascade Glacier.
Fyke net contents from a lake near Atqasuk, AlaskaFyke net contents from a lake near Atqasuk, AlaskaContents of the fyke net that was set in the lake near Atqasuk in 2016. All sticklebacks.
Contents of the fyke net that was set in the lake near Atqasuk in 2016. All sticklebacks.
Water quality measurements on the Pilgrim RiverCollecting water quality data on the Pilgrim River. Types of measurements taken were on water temperature, dissolved oxygen, pH, and conductivity.
Collecting water quality data on the Pilgrim River. Types of measurements taken were on water temperature, dissolved oxygen, pH, and conductivity.
Setting nets on Whitefish Lake on Lake Clark Nat'l Park and PreserveSetting nets on Whitefish Lake on Lake Clark Nat'l Park and PreserveRandy Brown and Dan Young are setting nets to catch whitefish on Whitefish Lake in the Lake Clark National Park and Preserve.
Randy Brown and Dan Young are setting nets to catch whitefish on Whitefish Lake in the Lake Clark National Park and Preserve.
Kijik LakeKijik Lake in Lake Clark National Park and Preserve, Alaska. USGS researchers study salmon ecology in cooperation with NPS.
Kijik Lake in Lake Clark National Park and Preserve, Alaska. USGS researchers study salmon ecology in cooperation with NPS.
Tanalian Mountain and Hardenburg Bay in Lake Clark, AlaskaTanalian Mountain and Hardenburg Bay in Lake Clark, AlaskaReflections of Tanalian Mountain and Hardenburg Bay in Lake Clark, Alaska. Near Port Alsworth.
Reflections of Tanalian Mountain and Hardenburg Bay in Lake Clark, Alaska. Near Port Alsworth.
Sorting through invertebrates from a north slope lake of AlaskaSorting through invertebrates from a north slope lake of AlaskaAs part of the Changing Arctic Ecosystem project, two biologists sampling invertebrates near the Chipp River area.
As part of the Changing Arctic Ecosystem project, two biologists sampling invertebrates near the Chipp River area.
Ice wedge polygons on the north slope of AlaskaIce wedge polygons near the Chipp River area on the north slope of Alaska
Ice wedge polygons near the Chipp River area on the north slope of Alaska
A north slope campAn enhanced photo of camp on the north slope.
Clear Montana Bill Creek flowing into volcanically silted creekClear Montana Bill Creek flowing into volcanically silted creekA clear Montana Bill Creek flowing into volcanically silted creek. Coho salmon are seen holding in the clear water area. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
A clear Montana Bill Creek flowing into volcanically silted creek. Coho salmon are seen holding in the clear water area. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Cannery Creek after the Redoubt Volcano eruption of 2009Cannery Creek after the Redoubt Volcano eruption of 2009Cannery Creek on the west side of Cook Inlet, Alaska. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Cannery Creek on the west side of Cook Inlet, Alaska. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Salmon in Montana Bill Creek after the Redoubt Volcano 2009 eruptionSalmon in Montana Bill Creek after the Redoubt Volcano 2009 eruptionA coho salmon holding in Montana Bill Creek after the Redoubt volcano eruption.
A coho salmon holding in Montana Bill Creek after the Redoubt volcano eruption.
Redoubt Volcano panorama with the Drift River DeltaRedoubt Volcano panorama with the Drift River DeltaA panorama of the Redoubt Volcano after the 2009 eruption and the Drift River delta in the foreground
A panorama of the Redoubt Volcano after the 2009 eruption and the Drift River delta in the foreground
The lower Drift River after the Redoubt Volcano 2009 eruptionThe lower Drift River after the Redoubt Volcano 2009 eruptionLower Drift River with tremendous amount of silt from the lahars. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Lower Drift River with tremendous amount of silt from the lahars. Aerial surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Drift River lahar from shore after the Redoubt Volcano 2009 eruptionDrift River lahar from shore after the Redoubt Volcano 2009 eruptionDrift River on the west side of Cook Inlet, Alaska. Lahars from the eruption of Redoubt are evident. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Drift River on the west side of Cook Inlet, Alaska. Lahars from the eruption of Redoubt are evident. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
A Drift River lahar after the Redoubt Volcano 2009 eruptionA Drift River lahar after the Redoubt Volcano 2009 eruptionDrift River on the west side of Cook Inlet, Alaska. Lahars from the eruption of Redoubt are evident. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams. Alaska Department of Fish and Game had done surveys in this particular area and found coho salmon before the eruption.
Drift River on the west side of Cook Inlet, Alaska. Lahars from the eruption of Redoubt are evident. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams. Alaska Department of Fish and Game had done surveys in this particular area and found coho salmon before the eruption.
View across the Drift River after the Redoubt Volcano 2009 eruptionView across the Drift River after the Redoubt Volcano 2009 eruptionView of the amount of lahar deposit from across the river and the amount of deposit the river has eroded out to sea in about 6 months. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
View of the amount of lahar deposit from across the river and the amount of deposit the river has eroded out to sea in about 6 months. Surveys were done after the eruption of the Redoubt volcano to determine the condition of fish streams.
Aerial view of the Lake Clark National Park and Preserve areaAerial view of the Lake Clark National Park and Preserve areaAerial views of Tuxedni Bay on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial views of Tuxedni Bay on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial view of the Lake Clark National Park and Preserve areaAerial view of the Lake Clark National Park and Preserve areaAerial views of Tuxedni Bay on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial views of Tuxedni Bay on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
A tributary of Lake Clark, AlaskaAerial views of streams on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
Aerial views of streams on the west side of Cook Inlet, Alaska. This was during surveys for juvenile salmon distribution for the Anadromous Fish Catalog for the State of Alaska.
- Publications
Filter Total Items: 70
Differential heat shock protein responses in two species of Pacific salmon and their utility in identifying heat stress
Rapid and accelerating warming of salmon habitat has the potential to lower productivity of Pacific salmon (Oncorhynchus species) populations. Heat stress biomarkers can indicate where warming is most likely affecting fish populations; however, we often lack clear classifications that separate individuals with and without heat stress needed to make these tools operational. We conducted a heat expoAuthorsVanessa R. von Biela, Amy M. Regish, Lizabeth Bowen, Ashley E. Stanek, Shannon C. Waters, Michael P. Carey, Christian E. Zimmerman, Jonathon Gerken, Daniel Rinella, Stephen D. McCormickElodea mediates juvenile salmon growth by altering physical structure in freshwater habitats
Invasive species introductions in high latitudes are accelerating and elevating the need to address questions of their effects on Subarctic and Arctic ecosystems. As a driver of ecosystem function, submerged aquatic vegetation is one of the most deleterious biological invasions to aquatic food webs. The aquatic plant Elodea spp. has potential to be a widespread invader to Arctic and Subarctic ecosAuthorsMichael P. Carey, Gordon H. Reeves, Suresh Sethi, Theresa L. Tanner, Daniel B. Young, Krista K. Bartz, Christian E. ZimmermanInvestigating effects of climate-induced changes in water temperature and diet on mercury concentrations in an Arctic freshwater forage fish
The amount of mercury (Hg) in Arctic lake food webs is, and will continue to be, affected by rapid, ongoing climate change. At warmer temperatures, fish require more energy to sustain growth; changes in their metabolic rates and consuming prey with potentially higher Hg concentrations could result in increased Hg accumulation. To examine the potential implications of climate warming on forage fishAuthorsSarah M. Laske, Samantha M. Burke, Michael P. Carey, Heidi K. Swanson, Christian E. ZimmermanFish ear stones offer climate change clues in Alaska's lakes
Otoliths, also known as ear stones, are small body parts that help fish with hearing and balance. Like tree rings, otoliths form one light and one dark band per year, creating rings. These rings can be measured to understand fish growth. The wider the ring, the greater the growth. In our study, we used otoliths to understand how one fish species—lake trout—responds to rising temperature in the staAuthorsKrista K. Bartz, Vanessa R. von Biela, Bryan A. Black, Daniel B. Young, Peter van der Sleen, Christian E. ZimmermanFirst juvenile Chum Salmon confirms successful reproduction for Pacific salmon in the North American Arctic
The distributional extent of Pacific salmon Oncorhynchus spp. in the North American Arctic is unresolved. While adult Pacific salmon have a recurring presence across the Alaskan North Slope and into the Canadian Arctic, it is uncertain if these fish are part of established Arctic populations, vagrants from outside sources reproducing unsuccessfully, or both. Here we present the first confirmed recAuthorsKaren M. Dunmall, Darcy G. McNicholl, Christian E. Zimmerman, Sara E. Gilk-Baumer, Sean E. Burril, Vanessa R. von BielaPremature mortality observations among Alaska’s Pacific salmon during record heat and drought in 2019
Widespread mortality of Pacific salmon Oncorhynchus spp. returning to spawn in Alaska coincided with record-breaking air temperatures and prolonged drought in summer 2019. Extreme environmental conditions are expected to happen more frequently with rapid climate change and challenge the notion that Alaska could indefinitely provide abundant, cool freshwater habitat for Pacific salmon. A total of 1AuthorsVanessa R. von Biela, Christopher J. Sergeant, Michael P. Carey, Zachary Liller, Charles M. Russell, Stephanie Quinn-Davidson, Peter S. Rand, P. A. H. Westley, Christian E. ZimmermanCircumpolar patterns of Arctic freshwater fish biodiversity: A baseline for monitoring
Climate change, biological invasions, and anthropogenic disturbance pose a threat to the biodiversity and function of Arctic freshwater ecosystems. Understanding potential changes in fish species distribution and richness is necessary, given the great importance of fish to the function of freshwater ecosystems and as a resource to humans. However, information gaps limit large-scale studies and ourAuthorsSarah M. Laske, Per-Arne Amundsen, Kirsten Christoffersen, Jaakko Erkinaro, Guðni Guðbergsson, Brian Hayden, Jani Heino, Kerstin Holmgren, Kimmo K. Kahilainen, Jennifer Lento, Panu Orell, Johan Östergren, Michael Power, Ruslan Rafikov, Atso Romakkaniemi, Martin-A. Svenning, Heidi K. Swanson, Matthew Whitman, Christian E. ZimmermanDiversity of diatoms, benthic macroinvertebrates, and fish varies in response to different environmental correlates in Arctic rivers across North America
Climate change poses a significant threat to Arctic freshwater biodiversity, but impacts depend upon the strength of organism response to climate‐related drivers. Currently, there is insufficient knowledge about Arctic freshwater biodiversity patterns to guide assessment, prediction, and management of biodiversity change.As part of the Circumpolar Biodiversity Monitoring Program's first freshwaterAuthorsJennifer Lento, Sarah M. Laske, Isabelle Lavoie, Daniel Bogan, Bob Brua, Stéphane Campeau, Krista Chin, Joseph M. Culp, Brianna Levenstein, Michael Power, Émilie Saulnier-Talbot, Rebecca Shaftel, Heidi K. Swanson, Matthew Whitman, Christian E. ZimmermanMigration strategies supporting salmonids in Arctic Rivers: A case study of Arctic Cisco and Dolly Varden
Amphidromous fish such as Dolly Varden (Salvelinus malma) and Arctic Cisco (Coregonus autumnalis) have distinct life histories that facilitate their success in Arctic environments. Both species spawn in freshwater and make annual migrations between marine, brackish, or freshwater environments. Dolly Varden rear for one or more years in freshwater before migrating to sea whereas Arctic Cisco migratAuthorsMichael P. Carey, Vanessa R. von Biela, Randy J Brown, Christian E. ZimmermanThe distribution of anadromy in steelhead / rainbow trout in the Eel River, northwestern California
To inform management and conservation of the species, we investigated the distribution of anadromy and residency of steelhead/rainbow trout (Oncorhynchus mykiss) in the Eel River of northwestern California. We determined maternal anadromy versus residency for 106 juvenile O. mykiss using otolith microchemistry. To attempt to relate patterns of anadromy with environmental factors known to influenceAuthorsBret C. Harvey, Rodney J. Nakamoto, Adam J.R. Kent, Christian E. ZimmermanEgg retention of high-latitude sockeye salmon (Oncorhynchus nerka) in the Pilgrim River, Alaska, during the Pacific marine heatwave of 2014–2016
Ocean and freshwater conditions can influence spawning success of Pacific salmon (Oncorhynchus spp.) by governing the energy content of fish at the start of and during the spawning migration. Ocean conditions determine the energy stores of fish at the freshwater entry, while freshwater conditions determine how quickly stored energy is depleted as individuals migrate to spawning grounds in natal riAuthorsMichael P. Carey, Vanessa R. von Biela, Ashley Dunker, Kevin D. Keith, Merlyn Schelske, Charlie Lean, Christian E. ZimmermanUSGS permafrost research determines the risks of permafrost thaw to biologic and hydrologic resources
The U.S. Geological Survey (USGS), in collaboration with university, Federal, Tribal, and independent partners, conducts fundamental research on the distribution, vulnerability, and importance of permafrost in arctic and boreal ecosystems. Scientists, land managers, and policy makers use USGS data to help make decisions for development, wildlife habitat, and other needs. Native villages and citiesAuthorsMark P. Waldrop, Lesleigh Anderson, Mark Dornblaser, Li H. Erikson, Ann E. Gibbs, Nicole M. Herman-Mercer, Stephanie R. James, Miriam C. Jones, Joshua C. Koch, Mary-Cathrine Leewis, Kristen L. Manies, Burke J. Minsley, Neal J. Pastick, Vijay Patil, Frank Urban, Michelle A. Walvoord, Kimberly P. Wickland, Christian ZimmermanByNatural Hazards Mission Area, Water Resources Mission Area, Climate Research and Development Program, Coastal and Marine Hazards and Resources Program, Land Change Science Program, Volcano Hazards Program, Earth Resources Observation and Science (EROS) Center , Geology, Geophysics, and Geochemistry Science Center, Geology, Minerals, Energy, and Geophysics Science Center, Geosciences and Environmental Change Science Center, Pacific Coastal and Marine Science Center, Volcano Science Center