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.
Return to Ecosystems >> Fish and Aquatic Ecology
This shift would essentially result in Arctic seas transforming to ecosystems that resemble their temperate southern counterparts and raises concerns for walrus and eiders that are adapted to feed on the historically rich community of abundant benthic organisms. As sea ice extent diminishes, more prolonged open-water phytoplankton blooms and increased zooplankton grazing may increasingly route surface primary production to pelagic consumers and away from the sea floor. The change in benthic production has been difficult to quantify, leaving resource managers with much uncertainty. We propose to relate annually resolved growth increments in benthic bivalves (clams) with satellite derived sea ice records to develop a predictive relationship between sea ice and benthic production in the Chukchi Sea. Bivalve clams are a key prey item for both walrus and eiders. The relative contributions of sea ice algae and phytoplankton, the two major sources of surface primary production, will also be described for bivalves using stable isotope analysis of soft tissue. Combining these products with model projections of future sea ice cover will allow us to predict the pace of shifts in benthic production, clarify the underlying mechanism, and enhance forecasts of the population response of DOI managed species to a changing Arctic environment.
Below are other science projects associated with this project.
Fish and Aquatic Ecology
Condition of Forage Fish in Prince William Sound During the Marine Heatwave
Winter Habitat of Juvenile Dolly Varden in the Canning River
Arctic Lake Food Webs
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
Effect of Elodea spp. on Fish Performance Mediated Through Food Web Interactions
Sockeye Salmon Migrating at the Northern Edge of Their Distribution
Nearshore Fish Surveys in the Beaufort Sea
Assessing heat stress in migrating Yukon River Chinook Salmon
- Overview
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.
Sources/Usage: Some content may have restrictions. Visit Media to see details.Annual growth increments in an acetate peel of Serripes groenlandicus clam collected in the northeastern Chukchi Sea.(Credit: Bryan Black, University of Texas, Marine Science Institute. Courtesy of Bryan Black, Limited Use by USGS Only) Return to Ecosystems >> Fish and Aquatic Ecology
This shift would essentially result in Arctic seas transforming to ecosystems that resemble their temperate southern counterparts and raises concerns for walrus and eiders that are adapted to feed on the historically rich community of abundant benthic organisms. As sea ice extent diminishes, more prolonged open-water phytoplankton blooms and increased zooplankton grazing may increasingly route surface primary production to pelagic consumers and away from the sea floor. The change in benthic production has been difficult to quantify, leaving resource managers with much uncertainty. We propose to relate annually resolved growth increments in benthic bivalves (clams) with satellite derived sea ice records to develop a predictive relationship between sea ice and benthic production in the Chukchi Sea. Bivalve clams are a key prey item for both walrus and eiders. The relative contributions of sea ice algae and phytoplankton, the two major sources of surface primary production, will also be described for bivalves using stable isotope analysis of soft tissue. Combining these products with model projections of future sea ice cover will allow us to predict the pace of shifts in benthic production, clarify the underlying mechanism, and enhance forecasts of the population response of DOI managed species to a changing Arctic environment.
Sources/Usage: Public Domain.Biologists sorting through buckets of benthic invertebrates looking for bivalves onboard the Norseman II in the Chukchi Sea.(Public domain.)
Sources/Usage: Public Domain.Benthic invertebrates captured in a bottom trawl. (Credit: Jannelle Trowbridge, USGS. Public domain.)
Sources/Usage: Public Domain.ANSEP intern, Jannelle Trowbridge, sorts through a catch of benthic invertebrates for bivalves on the Norseman II. (Credit: Vanessa von Biela, USGS. Public domain.)
Sources/Usage: Public Domain.The 2015 benthic field sampling team Jannelle Trowbridge, Vanessa von Biela, Carolynn Harris, and Thomas Nguyen. (Public domain.)
Sources/Usage: Public Domain. Visit Media to see details.Identifying and sorting clams by species. This sample came from benthic trawls on the Norseman II.(Credit: Jannelle Trowbridge, USGS. Public domain.)
Sources/Usage: Public Domain.Sea ice in the Chukchi Sea.(Credit: Jannelle Trowbridge, USGS. Public domain.)
Sources/Usage: Public Domain. Visit Media to see details.Pacific walrus hauled out on sea ice in the Chukchi Sea.(Credit: Tyrone Donnelly, USGS. Public domain.) - Science
Below are other science projects associated with this project.
Fish and Aquatic Ecology
Fish and aquatic habitats in Alaska support important commercial, sport, and subsistence fisheries and provide forage fish that support wildlife populations. The USGS Alaska Science Center conducts interdisciplinary research to inform local, state, federal, and international policy makers regarding conservation of fish, aquatic species, and their habitats. We work collaboratively with hydrologists...Condition of Forage Fish in Prince William Sound During the Marine Heatwave
Changes in the body condition of a key forage fish species, Pacific sand lance (Ammodytes personatus), are examined to understand how energy transfer to predators may have been disrupted during the recent marine heatwave in the North Pacific (late 2013 to mid 2016).Winter Habitat of Juvenile Dolly Varden in the Canning River
In the Arctic, rivers often freeze all the way to the bottom each winter leaving fish with limited habitat where they can survive.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.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.Effect of Elodea spp. on Fish Performance Mediated Through Food Web Interactions
The potential for invasive species introductions in Arctic and Subarctic ecosystems is growing as climate change manifests and human activity increases in high latitudes.Sockeye Salmon Migrating at the Northern Edge of Their Distribution
The physiological challenge for anadromous fish to migrate upriver to spawn and complete their life cycle is influenced by river temperature.Nearshore Fish Surveys in the Beaufort Sea
Nearshore systems provide habitat to a unique community of marine and diadromous (lives in both fresh and saltwater) fish and support high fish abundance.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. - Multimedia