Friday, June 17, 2016

Report on the Kokanee Salmon of Lake Sammamish

By Gary Smith
City of Redmond Parks and Trails Commissioner
Water Tender

Several years ago I reported on the declining number of Kokanee in Lake Sammamish (see the WaterTender Newsletter of Fall/Winter 2009).  It was a familiar story which I called “a dire situation” on waterways near modern developments that increase pollution, sediment buildup (siltation?), flash storm-runoff, and occasionally explosive algae growth.  Kokanee are dying early in increasing numbers, threatening the entire population.
Even though the US Fish and Wildlife Service finally in 2007 (?) declined to list the fish as endangered, local groups went ahead with restoration projects, and those grassroots efforts have shown positive effects.  Returns have been up and down – no surprise for salmon-watchers -- but nothing as perilously low as 2008 when fewer than 100 Kokanee spawned, according to King County spotters.  And a couple striking new developments in the story will bring this update to a more optimistic conclusion.
First, a couple basics:
·         Kokanee are the same species as sockeye salmon:  Oncorhynchus nerka (Also: Kickininee, land-locked sockeye; little redfish).
·         Unlike other salmonids, Kokanee complete their entire life cycle in fresh water, maturing in the lake and migrating into tributaries where they spawn and produce offspring imprinted with that natal water.
·         Lake Sammamish has 3 main tributaries with viable Kokanee runs:  Lewis, Ebright, and Laughing Jacobs Creeks (Issaquah Creek once had the largest migration, but it declined over the period of the state hatchery’s operation and was declared extirpated in 2002).  Read More >>

·         Over the past 7 years, each of these tributary runs has been supplemented with hatchery fry raised in its respective natal water and released in springtime (this spring, for the first time Issaquah Creek will receive transplants from other streams raised in at the Issaquah hatchery).  Several other creeks are also showing signs of life; for example, in the Redmond area Idylwood had several Kokanee this past spawning season, and I found a carcass on Bear a couple years ago (Dick Schaetzel and Ed Schein make similar claims).  These fish are probably strays because, to quote from a 2003 King County report:  “In the 1940s, the kokanee in Bear Creek were so prolific that they were considered to be the most important run of kokanee in the entire Lake Washington Basin . . . (but) by the early 1970s, the Bear Creek kokanee population was considered to be extinct” http://tinyurl.com/kokaneeupdate .
The supplementation plan was developed in 2007 by the Kokanee Work Group (KWG), which represents a myriad of government and non-government organizations, coordinated by a King County official.  The group is working to improve the health of this fish population so it becomes self-sustaining and would ultimately support fishing in the lake.  Over its 10-year history the KWG members have remained enthusiastic and have recently come together to sharpen the focus in two new public efforts: 
1.       In 2014, Sammamish Lake was named an Urban Wildlife Refuge, one of eight national programs designated by the US Fish and Wildlife Service.  Secretary of Interior Sally Jewell made the announcement in spring of that year at the annual Kokanee fry release, and since then, the Kokanee Work Group and other organizations have been building a constituency to conserve fish and wildlife in the central Puget Sound watershed, centered around the Kokanee.  For more info see www.fws.gov/urban/partnerships.php .
2.       Trout Unlimited is establishing a new position, the Lake Sammamish Kokanee Restoration Project Manager.  Supported by the Kokanee Work Group, this person could greatly accelerate the pace of projects already identified by the KWG to improve fish passage and habitat and could also initiate more youth education programs, community outreach events and citizen-science activities.
The overall effort is still aimed at restoring the Kokanee to a self-sustaining population which will support a fishery, but therein lies the rub:  because yearly numbers fluctuate so greatly, it’s not clear what level is sustainable and specifically when it will be possible to take fish for human consumption, the primary goal of some groups including the tribes.  At first glance, the problem doesn’t seem so complicated, at least not compared to the other salmon species.  Since they don’t typically go to sea, the Kokanee population is contained in a closed system, and the variables affecting mortality are relatively few.  Yet, the numbers fluctuate in patterns that perplex fish biologists.  The science is too complex for this short article, but here is an example of the unpredictable numbers.  2012 was the first year when hatchery fish were expected to spawn, and numbers were indeed higher that year, but analysis showed that only 9% of them were hatchery fish.  And in-between, 2013 was another near-disaster for the population:  only 141 Kokanee returned to spawn in the 3 major tributaries, nearly equaling the worst year on record, 2007 (over half the spawners were hatchery fish).  Success is still not certain, and therefore the supplementation effort will continue until more answers are found.  See the timeline for a simplified look at the KWG strategy for Lake Sammamish Kokanee.
Among the steps I suggested in my newsletter article 7 years ago was one that now presents an opportunity for Watertenders:  “Encourage local officials to improve stormwater management.”  With or without our prodding, King County has embarked on a new multi-year project to study stormwater issues in our Bear Creek watershed.  Initial meetings have already set the groundwork for a Stakeholder Workshop and a Public Meeting this fall, aiming to complete a final watershed plan for submission to the Washington State Department of Ecology in 2018.  For details see www.kingcounty.gov/BearCreekPlan .  It is a fitting follow-on to the county’s ground-breaking work done over 25 years ago in the watershed, resulting in the Bear Creek Basin Plan which recommended regulations for storm water retention and detention, forest cover, buffers, etc.  Seems to me worthy of continued Watertender attention.

  • The following is not science-based; it’s just a story I’ll call “Chicken and the Egg:”                           So which came first, the Kokanee or the Sockeye:  As a typical glacial lake in the Pacific Northwest, Lake Sammamish is theorized to have become populated with Kokanee during the Ice Age when migrating sockeyes were trapped.  They flourished, and tribal accounts emphasize the importance of this “little red fish” as a food source, smaller than the other salmon but available year-round.  But 100 years ago things changed when the Ballard Locks were built.  It’s believed that during construction when the lake level was dropping and the southern outlet of Lake Washington was shut off and the Black River disappeared, other populations of salmon died out in Lake Sammamish.  And so today, you will often hear that the salmon in the Lake Washington system are all hatchery fish.  This is certainly debatable, and as some of you WaterTenders may remember, we heard a talk (?) attesting to the wild genes in the Bear Creek sockeye population.  Perhaps those modern sockeye had transformed from their landlocked cousins.  Kokanee have been known to occasionally migrate to the ocean and return, so it’s conceivable that the contemporary sockeye has ancient genes preserved through the landlocked period by its cousin, the Kokanee.  (That’s just my speculation and is based on imperfect knowledge of changes in streamflows over the centuries -- see this source for a more factual history of the local Kokanee:  http://tinyurl.com/kokaneehistory .

  • Gary Smith
  • Redmond, WA

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