More Walleye Turn Up In Seattle Lakes

State, Tribal Netters Catch 13 Large Fish A Decade After First Discovery In Lake Washington; First One Found In Lake Sammamish Too.

By Andy Walgamott

MERCER ISLAND, Wash.—A 13.5-pound gravid female walleye is raising as many questions as eggs it could have released into Lake Washington this spring had it not been for a stroke of luck.

Gravid means the fish was ready to spawn, and five mature males that had also gathered off the shallow, windswept beach below the I-90 bridges between the island and Bellevue were more than willing to oblige her – until they too were gillnetted.

“They were spewing milt and she had eggs coming out of her vent,” said WDFW biologist Danny Garrett, who captured the sextet over the course of a week in March.

State fisheries biologist Danny Garrett scowls while holding a large male walleye netted on Lake Washington earlier this year. It was one of six he and fellow WDFW bio Aaron Bosworth hauled out of the waters near Enatai Beach, under the I-90 bridge between Mercer Island and Bellevue. (DANNY GARRETT)

State fisheries biologist Danny Garrett scowls while holding a large male walleye netted on Lake Washington earlier this year. It was one of six he and fellow WDFW bio Aaron Bosworth hauled out of the waters near Enatai Beach, under the I-90 bridge between Mercer Island and Bellevue. (DANNY GARRETT)

Along with seven more netted by Muckleshoot Tribe biologists, it represents a tripling of the number of walleye known to have come out of Lake Washington in the past 10 years. And this year also saw the first netted out of Lake Sammamish, at the other end of the King County watershed.

It begs the question, how many more might there be in the system? And who is behind the illegal introductions?

The latter is far easier to answer. Walleye are native to the Mississippi River and lower Missouri River basins, but in the 1930s and 1940s some had been moved west into Montana. In 1950, they were reported on this side of the Continental Divide, in Lake Roosevelt, and from there they spread inexorably throughout the Columbia Basin. With the Wanapum Pool just 100 miles to the east of the two Seattle lakes, and other impoundments of the federal hydropower and irrigation system such as Potholes Reservoir and Moses Lake not much further away on the interstate, it was inevitable walleye would cross the Cascades in livewells. Those netted this year were probably dumped into Lake Washington several years ago by local bucket biologists bent on creating new and much closer-to-home fisheries.

But it’s also possible the fish are the progeny of earlier illicitly stocked fish that successfully spawned in the lake, though no juvenile walleye have yet to be found in the King County watershed.

Nobody is actively looking for young walleye either, but that may change as ramifications begin to sink in with the many stakeholders.

IT’S UNDENIABLE THAT Lake Washington presents good walleye habitat, has several areas where the species can broadcast spawn, and offers a first-class forage base.

Walleye are not above chomping on their cousins, yellow perch, which the lake has scads of, and with their soft rays, northern pikeminnow could also prove to be a favorite.

But the fear is that as the walleye population grows, it has the potential to impact Endangered Species Act-listed Chinook and steelhead smolts, which transit through the lake from the Cedar River and Sammamish Slough. Young coho spawned in the system’s many tributaries also use the lake.

And then there are the sockeye salmon, which are produced at a new Seattle Public Utilities hatchery on the Cedar and spend more time in the lake than any other salmonid species. Though of late returns of the red salmon haven’t been big enough to open a recreational season – it’s unclear if that’s related to inlake predation by cutthroat, pikeminnow and smallmouth (the bass of Idaho’s Dworshak Reservoir are known to suspend in open water to prey on kokanee) or competition in the North Pacific with the outlandish numbers of pink salmon there, or all of it and more – anglers and sporting goods shops eagerly await the day that last decade’s legal wrangling over the multimillion-dollar facility begins to pay off, as no other fishery in Washington generates as much excitement as a Seattle sockeye season

Walleye were first confirmed in the lake in 2005 with a 16-inch male. Two more males were netted in both 2010 and 2011. There are rumors of angler catches before and since, and in winter 2010 a picture of a 22-inch, 5-pounder caught by a bass angler who was jigging near Coleman Point, north of the mouth of the Cedar, popped up. That’s near where the Muckleshoot Tribe netted one of their seven; the others came from the East Channel near the I-90 bridges. (A phone call to tribal counsel for comment was not returned.)

If all that were ever illicitly released were males, the population could only grow as fast as livewells could be emptied at Lake Washington’s many ramps, but March’s female shows that we can’t depend on the bad luck of bucket bios to only transport bucks. A hen of its size could theoretically have pumped out over three-quarters of a million eggs.

Mathematically, this 13.5-pound walleye could have released around 750,000 eggs had it not been caught in a gillnet set out to study different predators on Lake Washington. It now resides in a WDFW cooler. (DANNY GARRETT)

Mathematically, this 13.5-pound walleye could have released around 750,000 eggs had it not been caught in a gillnet set out to study different predators on Lake Washington. It now resides in a WDFW cooler. (DANNY GARRETT)

GARRETT WASN’T ACTUALLY after walleye that day when the big girl turned up. He was assisting University of Washington fisheries scientists building baseline data on Lake Washington’s cutts and pikeminnows. He let one net soak for an hour while he did some electroshocking, and then afterwards pulled it and was surprised when a walleye came over the gunnel. Over the next week he did more netting and ultimately caught six. The males were all 2-plus feet long.

“The last small one was the one caught in 2005,” Garrett notes.

While it’s only one walleye, the Sammamish fish was in the same system as an important state salmon hatchery which raises more than 2 million Chinook and coho annually to fuel sport and tribal fisheries (most years) in Marine Areas 9 and 10, the Ballard Locks and Lakes Washington and Sammamish. There are also ongoing federal, tribal, state, county and local efforts to recover the lake’s kokanee (Northwest Sportsman, April 2014).

Overall, it’s a troubling development. From a management standpoint, Lakes Washington and Sammamish are far too large to rotenone like fisheries managers might do elsewhere to control unwanted species. While intense gillnetting is being performed on the Pend Oreille River to tamp down its northern pike population, that’s a trickier proposition in Lake Washington because of the ESA listings. Basically, late winter is the window.

It also puts WDFW into yet another conflict with some warmwater anglers, who already feel put upon by the agency’s liberalization of walleye, bass and catfish rules in the Columbia system a couple years ago, and a sense that their species are the state’s proverbial red-headed stepkids to the golden ones – trout, salmon and steelhead, praise be their names.

And while it’s true that once upon a time, the bucket biologists wore government emblems on their sleeves, those days are now well past as new understandings of species’ impacts and new management challenges, such as ESA listings, have arisen. These days, fishery managers are going after problem species early to try and head off more serious issues down the road, like getting in front of pike before they spread into North-central Washington’s most productive salmon waters. While this year anglers have been catching northerns to 15 pounds near Kettle Falls on Lake Roosevelt, WDFW and tribes plan to gillnet next year.

And then there are the health concerns about eating an apex predator like walleye out of Lake Washington. Even if it isn’t the sewer it was in the 1950s, it’s anything but pristine. Its carp and pikeminnow are both on the no-fry list, and people are advised to eat just one meal of cutthroat a month and only one of yellow perch a week.

Though he knows of no tests done on the flesh of walleye from the lake, Garrett wonders if similar if not stronger warnings might be applied to the species. In their selfishness, bucket bios may not only have introduced a species that could deeply impact the lake’s ecosystem, but they may ultimately be advised not to eat their quarry. Muckleshoot fishery managers will get very little sympathy from sport anglers after what happened to the Area 10 king season at North of Falcon this year, but no doubt a Lake Washington trophy walleye catch-and-release fishery would be particularly galling to the tribe.

WDFW netters found the walleye off Enatai Beach, which is just south of the east end of the I-90 bridges between Mercer Island and Bellevue. It either represents a likely spawning area, or is close to lake accesses from which the fish were dumped. (NOAA)

WDFW netters found the walleye off Enatai Beach, which is just south of the east end of the I-90 bridges between Mercer Island and Bellevue. It either represents a likely spawning area, or is close to lake accesses from which the fish were dumped. (NOAA)

AS FOR NEXT steps, in Eastern Washington, WDFW biologists perform what is known as fall walleye index netting, or FWIN, surveys to figure out fish numbers on lakes the state does want the species, places such as Banks and Moses Lakes. Garrett says he’d like to net Enatai Beach in the future, where he caught the six fish, but efforts at the lake-level will be dependent on funding and support. Thus far, the University of Washington and the Muckleshoot Tribe have played pivotal roles in the discovery process.

Editor’s note: Anglers who catch walleye in the lakes are asked to call WDFW biologist Aaron Bosworth (425-775-1311) with info on length, sex and catch location.

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