Bering Science

Spring 2022

The Bering Sea is experiencing many changes. Here, we share observations and research that is happening in and around the region. This year’s report focuses on six topics identified by our Community Advisory Panel. The Alaska Ocean Observing System and International Arctic Research Center compiled the information from many sources, with funding from National Oceanic and Atmospheric Administration.

The Bering Region Ocean Update project began in spring 2020, in part, to increase regional data sharing among federal, state, community and private sector partners. This is the third report. Read previous updates and learn how information is gathered and reviewed.

We provide a resource to state, federal, community and university partners to share recent observations with community members and other scientists and management agencies.

If you gather data or have observations of changes in the Aleutians, Bering Sea or southern Chukchi Sea, please contact us for possible inclusion in a future Bering Science report.


Though state and federal management agencies, Tribal and science organizations contributed information and results to this Bering Science report, it is not a part of an official management process. It is not comprehensive and does not take the place of official documents like the NOAA Ecosystem Status Reports.

Throughout this report we have done our best to provide a well-rounded, synthesized and easy to understand perspective on salmon, halibut, walrus, crab and seabirds in the Bering Sea Region. We also provide examples of research happening on each topic, though much more work is being done than can be covered here.

Connie Melovidov holds a tagged snow crab in spring 2022 during a pilot study to monitor winter and spring
movements in the Bering Sea. Photo by Garrett Dunne.
Connie Melovidov holds a tagged snow crab in spring 2022 during a pilot study to monitor winter and spring movements in the Bering Sea. Photo by Garrett Dunne.

Who are we?

This report is part of the Alaska’s Changing Environment series. It was compiled by the Alaska Ocean Observing System and the International Arctic Research Center with collaboration from the National Oceanic and Atmospheric Administration.

Community Advisory Board

We thank our advisory board for providing direction and feedback. 

  • Chandra Poe, Qawalangin Tribe Of Unalaska
  • Connie Melovidov, University of Alaska Fairbanks
  • Craig Chythlook, UAF
  • Jennifer Hooper, Association of Village Council Presidents
  • Lauren Divine & Chris Tran, Ecosystem Conservation Office at Aleut Community of St. Paul Island
  • Mabel Baldwin Shaeffer, Alaska Fisheries Science Center
  • Melissa Maktuayaq Johnson, Interagency Arctic Research Policy Committee 

We also thank our reviewers who provided valuable input on this publication.

Suggested citation

Prewitt, J. and H. R. McFarland, editors. Bering Science: Spring 2022 Bering Region Ocean Update, Issue 4 [newsletter]. Alaska Ocean Observing System, Anchorage, Alaska.


Your opinion is valuable to us and can help guide future reports. Please provide feedback by filling out an online survey.



Salmon failed to return to western Alaska rivers in 2021. King, chum and silver salmon runs of all ages were impacted. These declines continue to cause severe hardship to communities in the region. Scientists and managers don’t know yet the exact reasons for the declines, but many studies are working to better understand salmon in the Bering Sea.

Researchers count and identify salmon caught in the Bering Sea. Photo courtesy of Alaska Department of Fish and Game.

What do we know?

Yukon River Chinook salmon abundance is driven by events very early in their life, before their first winter at sea. This is a particularly critical time in the life of salmon, when they face significant challenges to their survival.

Managers are now able to accurately forecast Yukon River Chinook salmon run abundance up to 3 years into the future. This helps managers and subsistence users plan ahead.

Changes in the marine environment affect salmon abundance, health and survival. New evidence suggests that marine heatwaves in the Bering Sea and Gulf of Alaska may be responsible for the chum declines. Warming ocean temperatures change the distribution and abundance of nutritious food for young salmon in the ocean. Scientists have found more young chum with empty stomachs and depleted fat reserves in the Bering Sea.

What don’t we know?

Too little is known about what happens to salmon in the ocean. Poor abundance isn’t just a problem for Chinook and chum salmon entering the northern Bering Sea (mostly from Yukon River and Norton Sound stocks). Chinook and chum salmon entering the southern Bering Sea (mostly from Kuskokwim River and Bristol Bay stocks) also declined in 2021.

Research priorities

Future research will assess juvenile Kuskokwim and Bristol Bay salmon that rear in the southeastern Bering Sea. Since chum (and other species) in western Alaska use both the Bering Sea and North Pacific Ocean during their marine life, a new study will look at what happens to salmon in the North Pacific Ocean.

Who’s doing the research?

Responding to marine salmon information needs, the Alaska Department of Fish and Game created the Salmon Ocean Ecology Program (contact: Katie Howard). They assess and monitor the marine life of Alaska salmon. The program collaborates with NOAA and other partners to assess salmon, including western Alaskan salmon, throughout the North Pacific Ocean and Bering Sea.

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We appreciate receiving information, input and developing partnerships with other organizations who also want to learn more about the marine life of salmon. By working together, we hope research will benefit the food security, fisheries management and economic stability of the region. Email

Warm water & salmon stress

Yukon river temperature

The low salmon returns followed several years of warm conditions in the Bering Sea and rivers from the Kuskokwim to the Yukon. In summer 2019, community members raised the alarm to scientists and managers. They reported bathtub-like river water and dead salmon that still had eggs, meaning they died before spawning.

This graph shows the maximum summer temperature of the Yukon River at Pilot Station. In 2019, it hit 70°F. Data from USGS, graph by Rick Thoman.

Bering Sea temperatures

This graph shows the average sea surface temperature from May to October from 1900–2021. Nine of the 10 warmest summers (red dots) occurred since 2000. Data from NOAA/ERSSTv5, graph by Rick Thoman.

Dead salmon

Chum salmon found dead along the Koyukok River in summer 2019. Since the eggs and sperm were retained the salmon died before spawning. Photo by Stephanie Quinn-Davidson.

Where were dead salmon found?

All five species of salmon were found from Prince William Sound and Bristol Bay in the south, to Norton Sound and the Yukon River in the north. Dead pink salmon were the most abundant in Norton Sound, chum in Yukon and Kuskokwim rivers, and red salmon in Bristol Bay. July marked the peak numbers of carcasses in western Alaska. This timing aligned with the warmest temperatures and lowest river levels.

Why is warm water bad?

Salmon need cool, oxygen-rich water to migrate, spawn and rear their young. Many rivers and streams still provide great salmon habitat, but some areas are becoming warmer and drier due to climate change. Lab tests showed that about 50% of king salmon returning to the Yukon River in 2016 and 2017 were stressed by the warm water. In other regions, this kind of stress has been tied to death before salmon are able to spawn.

What does this mean for managing salmon?

When salmon die before they spawn, the number of salmon entering rivers no longer provides an accurate estimate of how many eggs are laid in the gravel. This makes managing salmon and estimating the size of the next generation more challenging for managers.

Who’s doing the research?

Alaska Science Center, US Geological Survey (Contact: Vanessa von Biela).

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Report observations

Report unusual salmon observations, like carcasses with eggs or salmon avoiding warm water, to

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