AK - NOAA data on Alaska's oceans highlight warming trends
The annual Ecosystem Status Reports from the National Oceanic and Atmospheric Administration collect a wide range of data to better assess maritime trends and help steer fisheries management.
Elizabeth Siddon, who edited a report on the eastern Bering Sea, called the annual documents "anthologies of the ecosystems as we know them" - collaborative efforts pulling information from scientists, community members and industry groups, among others.
The reports released this week also cover the Gulf of Alaska and Aleutian Islands.
If there's any theme in this year's detailed surveys of Alaska's marine systems, it's heat.
The three areas assessed all involve "sustained warm conditions" that are affecting environment dynamics like sea ice and water columns, as well as the composition of animal stocks thriving and failing in recent years. The assessments factor into harvest policies set by the North Pacific Fisheries Management Council and touch any Alaskans who depend on sea animals, whether for work or food.
Many of the most startling trends in the reports are happening in the Bering Sea, which this year saw alarming declines in crab populations, abysmal salmon returns across Western Alaska and seabird die-offs.
"Although the collapses are coincident in 2021, they reflect cumulative dynamics over the last few years. The mechanisms are not fully understood, but a common thread in these collapses is the marine environment in the northern Bering Sea, which underwent an abrupt and dramatic change starting in late 2017," according to a brief on the full report.
The northward creep of groundfish stocks along with changing predation patterns in the ocean have been raising concerns about "food web dynamics and carrying capacity" in the northern Bering Sea for several years now, particularly around the shrinking pool of cold water on the seafloor south of St. Lawrence Island.
Farther south, data from community monitors on St. Paul Island has shown increasing salinity in the water from a loss of sea ice. That, in turn, is having an effect on the presence of algal coccolithophore blooms, dense blobs of rapidly expanding microscopic plants that can be toxic to animals or clog up ocean waters.