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 "
