June 24, 2026 — NOAA Fisheries scientists have completed a multi-year satellite tagging study of Pacific cod in the Bering Sea, shedding new light on how the species responds to warming ocean conditions and what those movements mean for fisheries management.
The study, launched in 2019 and led by Dr. Susanne McDermott of the Alaska Fisheries Science Center, was prompted by a dramatic northward shift in Pacific cod distribution that began in 2017, when the Bering Sea entered a period of unprecedented warming and sharply reduced sea ice. Pacific cod support Alaska’s second largest groundfish fishery and play a central role in the broader Bering Sea ecosystem.
“There was tremendous anxiety over what’s going on,” said McDermott. “Why are these fish in different places? Is this something that’s changing on a population level? Is this just the same population moving into different areas?”
To find answers, the research team — which also included fisheries biologists Julie Nielsen and Kimberly Rand — deployed pop-up satellite archival tags on cod in both summer and winter. The tags recorded depth, water temperature, light levels, and acceleration at intervals as short as one second, and transmitted that data to the Argos satellite network after detaching from the fish and surfacing. Tags that were physically recovered — returned by fishermen or beachcombers — yielded the full, unabridged dataset.