This is the first year the University of Washington Fisheries Research Institute has released a preliminary preseason forecast. Its scientists are predicting a run of just under 39 million sockeyes, 32% fewer fish than the 10-year average, and 19% fewer fish than the 20-year average. The projected harvest is approximately 26 million sockeye.
Curry Cunningham is a fisheries professor at the University of Alaska, Fairbanks, and a member of the research team. He said the preliminary forecast, which is for Bristol Bay generally, gives fishers perspective for next year a little earlier than usual.
“We wanted to put out a product a bit earlier, basically on a timeline when the last in-season daily release from the Alaska Department of Fish and Game was available,” he said. “Kind of end of July, beginning of August.”
This preliminary forecast is based on in-season estimates of total harvest and escapement numbers and in-season age information from the Alaska Department of Fish and Game.
By July 30, Fish and Game estimated a total run of about 53,000,000 sockeye in Bristol Bay, with a total catch of about 39,000,000.
Cunningham said that because the numbers aren’t finalized, and the by-river run reconstruction process has not yet been undertaken, the preliminary forecast is less accurate than the formal preseason forecast, released each year in November.
“The total sockeye salmon run to Bristol Bay, our standard preseason forecast or formal preseason forecast that comes out in November has an error rate of about 15%. This has a higher error rate of about 18% at the Bristol Bay scale,” he said.
Cunningham said both forecasts make predictions based on returning sockeyes’ ‘ocean age,’ or how long the fish have spent at sea. This year, he said more than 80% of returning fish were three-ocean sockeye. Cunningham said that’s usually as old as fish get before coming back.
“So a key part of the lower forecast this year: these systems change in productivity over time, number one. And number two, we were seeing this sort of strong cohort that was represented as two-ocean fish in 2022, and three-ocean fish in 2023,” he said. “They've now passed through the system, and it seems like we're going to see a slightly lower run next year.”
Next year, the report says, the researchers expect to 63% of returning sockeye to be ocean-two fish, which means fishers may notice smaller fish.
The report also shows a correlation between run size and sockeye size over the past 42 years, with larger runs resulting in a lower average weight for two-ocean and three-ocean fish. Cunningham says that may be due to competition.
“When you have a lot of juvenile sockeye going out that make up these big run sizes in subsequent years, they might be competing with one another for forage and food resources in the marine environment,” he said.
November’s formal preseason forecast, which is modeled with finalized data, will include details on how many fish to expect in each district, and run times.
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