Before emerging from the creek on a cold, sunny December morning, Dan Lantz pulled out a notebook to record a very familiar number this kokanee spawning season — zero.
Lantz, an environmental scientist for King County, and other fish ecologists were expecting a low return of kokanee this year. Spawning runs are typically cyclical, with boom and bust years. But nobody expected the numbers to be this bad.
As he walked, Lantz poked and prodded the vegetation along the creek, searching for any sign of the fish. Using polarizing glasses, he scanned the creek.
Before spawning, a female digs a nest, also known as a redd, in the gravel on the bottom of the creek bed, where she deposits her eggs in several depressions. These eggs will incubate until early spring. Come May, the inch-long fry will wiggle out of the gravel, making their way to Lake Sammamish. There, they will spend the next two to three years growing to be 12-14 inches long, before migrating back upstream.
“Last year, this area was just stocked full of redds, but not this year,” Lantz said.
Each year during the winter run, which usually occurs in November and December, scientists survey Lewis, Ebright and Laughing Jacobs Creeks three times a week.
Today, all Lantz encountered was a partially eaten kokanee head and a redd that may have contained eggs. He marked the nest and moved on.
“As of mid-January, our surveys indicated that 60-70 fish have returned to spawning tributaries across the entire lake,” said Jim Bower, a fish ecologist with King County.
Almost 6,000 kokanee were seen the year before.
“It’s not a good situation,” said David St. John, a policy adviser for King County and chair of the Kokanee Work Group. The group is a conglomerate of watershed residents, the Snoqualmie Tribe, local municipalities, government agencies and many environmental groups, all working to protect the fish.
St. John said that when the number of actively reproducing salmon dips below 500, the population is impacted. Such small numbers risk leading to functional extinction, and the reduced genetic stock could result in inbreeding problems.
Scientists propose many reasons for the low return this year, such as lake temperature, disease or predation.
Bower said, “Something is occurring in the lake that affects the whole cohort.”
A 40-year decline
The kokanee, a type of landlocked sockeye salmon, were once prominent across the Lake Washington watershed, spawning in more than a dozen streams around Lake Sammamish. Historically, migrating runs occurred twice a year, in the summer and winter. A 1975 summer survey estimated 15,000 were present in Issaquah Creek. By 2001, no kokanee were found and the summer run was declared extinct, according to the Kokanee Work Group.
Kokanee spend their entire lives in freshwater, in contrast with a relative of theirs, the sockeye salmon. Due to drastic reductions in suitable habitat, the kokanee now only spawn consistently in a handful of creeks: Lewis, Laughing Jacobs, Ebright, Pine Lake and occasionally in Tibbetts and Vasa creeks, as well.
Lacking a wide geographic distribution of spawning areas significantly increases the potential a single catastrophic event — natural or human-caused — could wipe out the entire population from the Lake Sammamish area.
In 2007, the Lake Sammamish Kokanee Work Group was assembled in response to the population decline that has nearly driven the kokanee in Lake Sammamish to extinction over the past 40 years.
The ad-hoc group devised a two-part plan to stabilize and rebuild the kokanee population: a short-term supplementation program to increase egg-to-fry survival rate and habitat restoration projects to improve spawning grounds.
In the fall of 2012, the group completed a massive habitat restoration project along Ebright Creek, largely funded by local landowner Wally Pereyra. A barrier preventing fish passage was replaced, opening up spawning habitat that hadn’t been easily accessible for decades. Non-native plants were removed. The slope angle of the creek’s banks was reduced to lessen the speed and power of water flows during high flood events, which can be damaging to egg nests.
All this work has tripled the spawning area along Ebright Creek.
“Within two weeks, fish were found above that culvert,” St. John said. “It’s the best habitat we have for kokanee spawning.”
“One thing we have control over is improving the habitat the best we can,” Bowers said.
Cooperation from nearby landowners is essential to the success of the massive habitat restoration projects because much of this work happens on private land. Often these projects rely on the partnerships of 10 to 30 landowners.
“All it takes is for one landowner to say no to stop a project,” Bowers said. “When you have the support and understanding of the landowners, it makes the project easier.”
The City of Sammamish is beginning a similar project on Zaccuse Creek, replacing a culvert running below the East Lake Sammamish Parkway to allow for fish passage.
“This project makes accessible a least a quarter of mile of very high quality spawning habitat,” Bower said. “That will support at least 2,000 to 3,000 fish.”
Empty tanks at the hatchery
Millions of coho and sockeye salmon eggs sit incubating in water tanks at the Issaquah Salmon Hatchery. After hatching, the fry move to rearing tanks until they are released a few months later.
A separate tank, prepared for kokanee eggs, remains empty.
In addition to restoring habitat, the Kokanee Work Group is more than halfway through a 12-year spawning program, started in 2009, to build resiliency into the population by boosting fry survival.
Due to the extremely low return this year, scientists are far from their goal of collecting 60,000 kokanee eggs, leaving hatchery tanks barren. This year marks the first time since the inception of the Kokanee Work Group that the annual Lake Sammamish kokanee fry release will be fishless.
St. John said the event will happen again this year, but with different activities.
Despite the low numbers of returning fish, the Kokanee Work Group is forging ahead, working on other adaptive management strategies.
“We may change some of our future practices with kokanee that are spawned and incubated at the hatchery to better match those of naturally produced fry,” Bower said.
“One of the concerns we have are the (hatchery fish) are stronger and more fit when they enter the lake (than wild fish). However, because of their size, they may be more vulnerable to predation,” Bower said.
Hatchery fish receive more food than wild fry.
“An adaptive management strategy may include feeding half the fish and not feeding the other half in order to evaluate the survival of those two groups,” Bower said.
Another strategy the group is experimenting with is placing nesting boxes near creeks to better mimic conditions in the wild.
The Kokanee Work Group is in the process of evaluating the effectiveness of the program. As more and more information and data is collected, more questions arise.
“Every lake system is different, every run is different,” Bower said. “We are learning as we go with the Lake Sammamish population.”