The harbor seal diet studies (scat samples) from the late 1990s and early 2000s provides some interesting observations.

In Hood Canal during the fall 79% of the samples contained gadids (primarily hake), 30% herring and 26% adult salmon. During the spring 85% of the samples were gadids, herring 26% and anchovy 35%.

In South Sound 99% of the had gadids (hake and tomcod) herring 69%, midshipman 37% and various flatfish 33%.

Juvenile salmonids were consumed by the harbor seals with the heaviest rates in the spring but in terms of both numbers and biomass they are minor portion of the harbor seals diet though a small portion of an individual seal diet can add up to a significant number for the population as a whole.

Regarding the hake between 1980 and late 1990s there was a decline in abundance for the inland (Georgia straits and Puget Sound) Distinct Population Segment (DPS) and is currently listed as a federal species of concern. If the Puget Sound portion of the DPS was considered separately the status concerns would increase. In that period a decline in both size and average weight was noted in the hake.

A major hake historic PS spawning area was Port Susan WDFW monitoring of the spawning biomass for the period 1980 and 2000 showed an 85% decline.

The long trend in herring abundance is no more encouraging. Since the mid-1970s WDFW has been monitoring various spawning aggregations annual (estimating the spawning biomass). WDFW produces a status report on the population trends every 4 years. As part of that evaluation stocks that fall below 25% of the running 25-year average are giving status rating of critical. In 1996 none of the 17 populations monitored given a critical. In the most recent report (2016 - the 2020 report should be available soon) of the 18 populations rated 9 (50%) were rated as critical.

The question we all quickly jump to is whether these as well as Chinook, coho and steelhead smolt survivals declines are all due to seal pinniped predation or some other large ecosystem problem is unknown and can't be known without more holistic evaluation of the PS ecosystem.

curt