Forage Fish
Biomass of spawning Pacific Herring

The biomass of spawning Pacific Herring indicator is the estimated annual tonnage (four-year average) of herring that have reproduced in Puget Sound. Estimates are based on surveys of the density and extent of eggs deposited by herring on marine vegetation. Herring, along with a few other small schooling fish species, play a unique role in the food web: they are an essential source of food for larger fish, seabirds, and marine mammals.

Four-year average spawning biomass estimates for three genetic stock groups and the combined total are shown with dashed and solid lines; dashed lines represent periods of incomplete data; each color corresponds to a different stock group, and black is the combined total of all stocks. The 25-year mean (1986-2010) for each stock is referenced as a baseline and is shown with horizontal dotted lines of corresponding colors.

Key Vital Sign Indicator Results

  • For the second year in a row, the 4-year average spawning biomass for the Other Stocks Complex was above the 25-year baseline. This group consists of all Puget Sound herring stocks other than Cherry Point and Squaxin Pass. In comparison, the 4-year averages of the genetically distinct Cherry Point and Squaxin Pass stocks remain below their baselines. Therefore, our conclusion about progress of Pacific Herring stocks in Puget Sound is “Mixed.”
  • We estimate 12,931 metric tons of total herring spawning biomass for the southern Salish Sea in 2022. This is an increase of about 26% from 2021, but a decrease of about 30% from the recent high estimate of 18,559 metric tons in 2020 (click here to download a table of annual biomass estimates). 
  • The Cherry Point herring stock, once the largest stock in Puget Sound, is estimated to be less than 1% of its historic high and shows no sign of recovery. The Cherry Point spawning biomass estimate in 2022 was the lowest on record.
  • During the 2022 season, WDFW surveyors failed to detect spawning in Holmes Harbor for the first time in the survey’s history, and for the second year in a row, we observed no spawning in South Hood Canal.
  • Record high spawning estimates were observed in 2022 at the Dungeness/Sequim Bay and Interior San Juan Islands spawning areas. Both areas exceeded their previous high estimates by over 800 metric tons and were more than 1,000 tonnes greater than their previous estimated spawning biomass.
  • During the 2022 season we continued to observe shifts in spawning distribution for some stocks and once again observed herring spawning in areas that had not been previously documented.

Contributing Partners


No targets are currently set for this indicator.

Data Source

Washington State Department of Fish and Wildlife, Marine Fish Unit (Forage Fish)

Vital Sign Indicator Reporter
Indicator Details
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