Several million freshwater shrimp started their day with clear, bright skies, abundant space and few predators in sight Thursday at Stormy Lake near Nikiski.
But all of that changed around 4:30 p.m. when the Alaska Department of Fish and Game backed a truck to the edge of the lake and Rob Massengill, fishery biologist, launched more than 6,800 arctic char into the water.
“Fish will have a buffet waiting for them,” Massengill said. “I would think they’re going to have pretty good pickings.”
The latest fish release is the last in a round of re-introductions to the lake that included longnose suckers, rainbow trout and coho salmon rescued before the department treated the lake with Rotenone — a plant-based fish-killer — last fall.
The fish kill was the largest invasive northern pike eradication project in the state and Massengill said he’s fairly certain Fish and Game achieved its objective.
“It’s hard to prove a negative but we’ve collected water samples that will be analyzed for pike cells, we’ve netted (the lake), we radio tagged about 13 northern pike before the treatment to see what they would do during the treatment and they were all dead before we were done,” he said.
Researchers also collected water samples to make sure the Rotenone reached the saturation levels necessary to kill fish.
“It did and it stayed that way ‘til the middle of January, so from early September to the middle of January this lake was toxic to fish,” he said. “Then we also put cages throughout the lake during the treatment and during this winter we placed them in different spots and depths; it always killed fish like it was supposed to ... all of the tools that we have indicate that the treatment was a success.”
Before the truck arrived, Massengill walked along the boundary of the lake to a gate put in by Fish and Game about a decade ago to keep the pike out of the Swanson River drainage and protect vulnerable coho salmon in the area.
Last week, he saw several rainbow trout holding near the gate and thought they could have come up from the Swanson River drainage and into the lake.
He did not have any luck finding the rainbows but spotted a coho salmon in the grassy area along the shoreline.
“Last year, I’d walk through here and I’d usually kick out pike in these shallows,” he said.
The pervasive pike were part of the reason biologists were so concerned about treating Stormy Lake.
“The Swanson River has got a perfect pike habitat,” Massengill said. “If they got a foothold in there, they could really change things ... there are a lot of coho salmon, rainbow in there, there’s a lot of interconnected lakes, weedy environments ... there’s a lot of vegetation. That’s the stuff pike like, weedy, shallow water,” he said. “So if they got out of here and established themselves out there in the stream, we could really see a big loss in the native coho and rainbow fishery there.”
Ricky Gease, Executive Director of the Kenai River Sportfishing Association, was on site to see the fish release as was Mikaela Pitsch, a middle school student who spent the last year educating people about the dangers of pike.
Chuck Pratt, a fisheries culturist, brought the char down from the Fort Richardson Hatchery where they were reared after Fish and Game took several females from the lake in 2011 and bred them with male arctic char from Dolly Varden Lake.
Massengill said of the more than 20 dozen char Fish and Game were able to retrieve from the lake, only two were male and they did not survive.
So, researchers had to interbreed with fish from another nearby lake to keep the genetically distinct population of Stormy Lake char — known for reaching more than eight pounds in their lifetime — from dying off.
While boats will be prohibited on Stormy Lake for the summer, due to another invasive species — the plant Elodea — Massengill said anglers could fish if they were interested.
They should not expect to find many large fish, however, as fish populations in the lake will take years to rebound to pre-pike levels.
Massengill said the Kenai River Sportfishing Association, Kenai Watershed Forum and U.S. Fish and Wildlife contributed significant amounts of money and time to the project to ensure its success and he was surprised and grateful for the community support.
“Sometimes these projects can be contentious, but everyone came together for this one,” he said.
If any pike survived the treatment, which he estimated cost more than a half-a-million dollars in the last two years alone, he said he would be stunned.
“If pike show up here, I personally will be convinced they were brought in by somebody and that’s the message we’re trying to get out is, we’re rebuilding this fishery, we’re restoring it,” he said.
Rashah McChesney can be reached at firstname.lastname@example.org.