By RALPH BARTHOLDT
COOLIN — Mackinaw are disruptive to fisheries in the Northwest and are being removed in many lakes in an effort to re-establish native fish, or, the kind of fish a lot of people like to catch, Idaho Department of Fish and Game biologists told a crowd of about 50 Thursday night in Coolin.
Often, that means establishing a fishery that favors kokanee.
But Idaho Fish and Game fishery managers Andy Dux and Rob Ryan, who played host at Thursday’s Priest Lake fishery management meeting, aren’t sold on the idea of building a strong kokanee fishery in Priest Lake such as one that existed a half century ago.
They don’t even know if it’s possible.
“Can we get what we had all the way back in the 1950s?” Dux asked. “I don’t know. It’s an altered system now.”
Back then, the lake was primarily known as a cutthroat trout fishery, Dux said. The native cutthroat trout are found in smaller numbers these days and anglers don’t often target them.
There have been a lot of changes in the Priest Lake fishery over the years, he said.
Mysis shrimp, a freshwater invertebrate that was considered a kokanee food source, were added in the 1960s in an effort to increase kokanee size.
Biologists learned, however, that the shrimp competed with kokanee for zooplankton, an important kokanee food source. The game fish’s numbers started to decline and haven’t bounced back. Competition for its food source caused Priest Lake kokanee to bottom out in the 1970s, which was an unforeseen and unfortunate turn of events in a lake that had a prime kokanee fishery.
The addition of mysis, however, bolstered the size and number of lake trout, which fed on the shrimp that pooled near the bottom of the lake in the daytime — the same place where lake trout live.
Planted in Priest Lake more than 100 years ago, lake trout — also known as mackinaw — took advantage of the introduced mysis shrimp, gobbling them, growing trophy fat and turning the tables at Priest Lake.
By the 1980s, Priest Lake was known as a trophy lake trout fishery.
In the meantime, bull trout, which were never greatly abundant in Priest Lake, were relegated to Upper Priest Lake where Fish and Game began in the 1980s supporting them by gill-netting the lake trout that swim up the channel from the main lake to feed on small bulls.
“We’re still doing that,” Ryan said.
Dux and Ryan presented three alternatives to anglers at Thursday’s evening meeting at The Inn on Priest Lake. Alternatives developed by a citizen advisory committee include managing the lake to support sustainable kokanee, cutthroat and bull trout fisheries, similar to the lake’s heyday fishery of the 1950s and ’60s. This alternative would require removing lake trout.
Or, Dux and Ryan said, the department could attempt to manage the lake for all species including lakers. If it works, the result could be a decent angling experience for many people with varying aims. That is a costly option.
Fish and Game could also do nothing, leaving alone the fishery in the main lake.
“Funding is a big question,” Dux said. “There are a lot of unknowns.”
Longtime Priest Lake angler Brian McInerney was certain about one thing.
“Leave it alone,” McInerney said.
If funding is in question, McInerney asked, why pursue another management option?
“It doesn’t cost anything to manage this lake right now,” he said.
McInerney, who has fished Priest Lake since the 1940s, prefers kokanee over Mackinaw, he said, but he enjoys catching and eating both species. Last year he regularly caught 16-inch kokanee in Priest Lake. He hasn’t fished for kokanee this summer, although he caught a few macks that he smoked.
“I prefer them that way,” he said. “They are a fabulous fish.”
Fishing guide Rick Horey agreed.
“A lot of us are really happy with it right now,” Horey said. “It costs nothing to manage this fishery right now.”
Disgruntled audience members who accused Fish and Game of pushing an agenda to manage against lake trout were rebutted.
“We’re not advocating for change,” Dux said. “We’re just going to the public to see what you want for this fishery.”