A new federal report on Alaska ecosystems warns that the current El Nino status and associated warming surface waters predicted for the winter and spring of 2024 may result in reduced availability of Gulf of Alaska zooplankton needed by many groundfish and reduced quality of that zooplankton itself.
According to NOAA Administrator Rick Spinrad, the overriding message from this year’s report card is that now in the time for action.
“NOAA and our federal partners have ramped up our support and collaboration with state, tribal and local communities to help build climate resilience,” Spinrad said. “At the same time, we as a nation and global community must dramatically reduce greenhouse gas emissions that are driving these changes.”
The 2023 Gulf of Alaska Ecosystem Status Report is part of NOAA’s 2023 Arctic Report Card, a cooperative effort of federal and state agencies and numerous other collaborators.
The report — released on Dec. 14 during the annual meeting of the American Geophysical Union in San Francisco — notes that the Gulf of Alaska shelf marine ecosystem had an average year of productivity in 2023, continuing a multi-year trend that is expected to change in 2024.
Given current El Nino status and the associated warming surface of gulf waters predicted this winter, the reduction in zooplankton availability and quality may persist into the coming year, the report said.
Signs of a restricted zooplankton prey base include:
-A decline from above average to average productive success for zooplankton-eating seabirds;
-Skinnier adult pollock;
-Below average energy density of juvenile salmon;
-And juvenile pink salmon diet comminated by jellyfish, tunicates and other gelatinous prey.
Predictions for 2024 returns of pink salmon are less favorable based on juvenile catch per unit effort (CPUE), length and energy density in 2013, the report said.
Forage fish, prey for Pacific cod, sablefish, arrowtooth flounder, yelloweye rockfish, varied across the gulf and included increased capelin. Populations of sablefish and Pacific Ocean perch increased while numbers of Pacific cod, Pacific halibut and arrowtooth flounder were reduced, the report said.
The overall document, now in its 18th edition, offers updates on the status of Alaska’s environment, which is changing more rapidly than anticipated, as well as insights on the Canadian Arctic, including the Northwest Territories. Eighty-two authors from 13 countries contributed to the document.
Above surface air temperatures for the Arctic as a whole from October 2022 through September 2023 were the sixth warmest since 1900, and the summer of July through September of 2023 was the warmest on record. Still there were important regional differences, including a colder-than-normal spring across Alaska that slowed snowpack and sea-ice melt, while parts of north-central Canada experienced the highest spring average temperatures on record.
Sea ice extent continues to decline, with the 17 lowest Arctic Sea ice extents on record occurring during the last 17 years. This year’s sea ice extent was the sixth lowest in the satellite record, which began in 1979, with older, thicker multi-year ice far less than in the 1980s.
The report also notes that Arctic Ocean regions, except for the Canadian Archipelago, Chukchi and Beaufort seas, continue to show increased ocean phytoplankton blooms, or primary productivity, with the largest percent increases in Eurasian Arctic and Barents Sea.
One new chapter in the report focuses on salmon species vital to the culture and food security of many Indigenous communities, as well as coastal fishing economies. In 2021 and 2022 sockeye salmon reached record high abundance in Bristol Bay, while Chinook and chum salmon on the Yukon and Kuskokwim rivers fell to record low numbers, resulting in fishing closures on those rivers in 2023. The report notes that sockeyes have been extremely successful under recent warm conditions, which allow them to grow faster in lakes as juveniles and may boost their survival when they migrate to the ocean. The diverging impacts are affecting Indigenous communities dependent on salmon for food, and challenging fishery managers as different species respond in unique ways to warming climate.
The report also features two chapters on the importance of implementing Indigenous knowledge for the future resilience of the Arctic.
Researchers Rick Thoman, of the International Arctic Research Center at the University of Alaska Fairbanks, and Daniel Schindler of the University of Washington’s School of Aquatic and Fishery Sciences, said that they remain overall optimistic.
“I am optimistic that Alaskans will adapt because we have no choice,” said Thoman, one of the lead authors of the report card. “It seems perfectly clear at this point that we are going to do things differently than in the past. But it is going to be a different Alaska than what we are used it.”
“Am I optimistic? We have to be,” Schindler told The Cordova Times in an email. “I think we need to separate the long-term needs from the short-term needs. The progress made at the global level via COP28 meetings etc. is pretty dismal. We might get to a point where we can reverse global trends in emissions but this is taking a very long time to play out. But we can’t wait for the global strategy to fall into place before we do tangible work at local and regional scales to reduce climate impacts.”
Schindler noted that slowing climate change is a very sluggish process.
“Even if we could drastically reduce greenhouse gas emission at the snap of our fingers, we will be living in a warmer future for most of the next century,” he said. “Most of the human-caused change to our climate system has been to heat up the oceans, which will take a very long time (on the order of several decades) to cool off,” he said.
“The other reality is that there are things we can do to manage climate impacts on ecosystems — right now,” he continued. “In fisheries, I think we can do several things to give fishes a good chance of coping with climate change. This includes actions like protecting and restoring habitat, having harvest policies that are responsive to changes in the productivity of fish populations, effectively monitoring fish populations to keep our finger on the pulse so that harvest rates can be adjusted accordingly, reducing additional stresses on populations like pollutants.”
