As a fish photographer, I often notice that steelhead carry that classic V shaped bite mark indicating a close encounter with a seal or sea lion. In recent years it seems to me that a high percentage of steelhead have had close encounters with the barking horde. In your experience what percentage of the steelhead you have caught had seal or sea lion bites?

The Marine Mammal Protection Act was passed in 1972. Since then, the pinniped population of Puget Sound has been increasing exponentially. Two of particular concern in Puget Sound are the Harbor Seal and the California sea lion. Harbor seals are year round residents of Puget Sound. California sea lions migrate into the Sound around September of each year and usually migrate out by April.


Some studies have been conducted on pinnipeds, their increase in Puget Sound since the Marine Mammal Protection and their eating habits:

- In a recent article published in the Journal of Wildlife Management, the authors reported that from 1978 to 1999, the Harbor Seal population in Washington State increased from 6,786 to 19,379. (Jeffries, S.J., H. R. Huber, J. Calambokidis, and J.L. Laake. 2003. Trends and status of harbor seals in Washington State: 1978-1999. Journal of Wildlife Management. 67 (1): 208-219.) Estimates are the harbor seal population in the Sound increases at the rate of about 4% annually. Harbor seals live to an average age of 25 years.


- "...Salmon accounted for 50% and 87% of observed captures of single, large fish in 1996 and 1997, respectively. Predation on schooling fishes involved juvenile sandlance or herring..." (Zamon, J.E. (2001). Seal Predation On Salmon and Forage Fish Schools As A Function of Tidal Currents In The San Juan Islands, Washington, USA, Fisheries Oceanography Volume 10 Issue 4 Page 353 - December 2001)


- "...In 1996, a single California sea lion was observed to kill 136 coho salmon in 62 hours (2.1 coho per hour.) The highest predation rates observed for this animal were 18 coho salmon over 4.4 hours (4.1 fish per hour). The maximum number of coho observed killed by this sea lion during any one day was 19 coho salmon in 6.9 hours (2.7 fish per hour.)" (National Marine Fisheries Service (NMFS). 1997. Investigation of Scientific Information on the Impacts of California Sea Lions and Pacific Harbor Seals on Salmonids and on the Coastal Ecosystems of Washington, Oregon, and California. U.S. Dep. Commer., NOAA Tech. Memo. NMFS-NWFSC-28, 172 p.)

The 1996 estimate of the number of California sea lions in Puget Sound was over 1,000. Their numbers haven't dwindled. Add to that the increasing number of harbor seals and the combined pinniped eating habits. Assuming all have similar voracious appetites as the sea lion described above, we're talking about putting a major dent in marine survival of anadramous species and forage.

When its time for lunch, pinnipeds don't discriminate between a hatchery or wild fish or one that is ESA listed.


Remember Hershel at the Ballard Locks a few years ago?

We have the same problem here in BC. I dont know about the whole province, but in the Fraser Valley, about half of the steelheads I catch have the seal scars on them. Once I caught one that had its roe exposed with a gaping hole on one side. Over on Vancouver Island, its just as bad if not worse.

The majority of my fishing this season has been in SW WA rivers, and I'm seeing about 10% of the wild steelhead I have been catching, with bite marks on them. One that was over 21 lbs, had 3 deep fresh bite marks on it, but only on one side. The other side was clean. Don't know how that can happen that way, but it was.
Catarafter