|August 8, 2013
Tribes float aggressive lake trout management proposal
By Allison Mills for Science Source
Credit: Shannon Downey, USFWS
PABLO — The popular Mack Days fishing derbies pull about 50,000 lake trout from Flathead Lake every year. For a decade the twice-a-year contests have been the primary tool for keeping the non-native fish in check. But Confederated Salish and Kootenai Tribes’ (CSKT) fishery managers say it’s not enough.
The more than 1.5 million lake trout in Flathead Lake and surrounding river system have crowded out native bull trout. There are now only about 3,000 adult bull trout, compared to 700,000 adult lake trout, in an ecosystem where the predatory fish, the largest native trout in the Pacific Northwest, once thrived.
Last Thursday, at Salish Kootenai College in Pablo, CSKT fishery managers presented their ideas for restoring balance between lake trout and bull trout. The meeting followed the June release of the tribes’ draft Environmental Impact Statement, which lays out options for culling more lake trout and boosting bull trout numbers. The proposals include bounties, commercial fishing, trap netting and gillnetting, with annual lake trout harvests projected to be between 70,000 to 143,000 fish.
“We’re not achieving our goals, we need more tools,” Barry Hansen, a biologist with the tribal fisheries program, said during the meeting, attended by about 40 people.
But the agencies managing the lake disagree on the goals and tools—and on the science behind them. The tribes manage the southern half of the lake, while the state manages the northern half. The tribes and the federal government, which considers bull trout “threatened” under the Endangered Species Act, prioritize bull trout recovery and advocate for aggressive lake trout management. Montana Fish, Wildlife and Parks believes angling alone is sufficient to control lake trout and keep bull trout above secure levels.
The two sides have decidedly different definitions of “secure.” The state says bull trout populations are 60 percent above secure levels, but that number is partly based on bull trout spawning data that a U.S. Fish and Wildlife Service biologist recently called “garbage.”
Bull trout numbers plummeted after the introduction of Mysis shrimp in the 1980s, an event that significantly altered the ecology of Flathead Lake. Lake trout, which the federal government introduced into the lake more than a century ago, thrived on the new food source, outcompeting bull trout. When lake trout management began in 2000, biologists noted a small bull trout bounce-back, though both populations have since plateaued.
“We’re not proposing to put it back the way it was,” Hansen said last Thursday. “We’re proposing to intervene in a controlled and monitored manner to maintain the heritage and biodiversity that we inherited there and have the responsibility to perpetuate.”
While “everyone wants more bull trout,” as FWP fishery biologist Mark Deleray says, the state also wants to perpetuate recreational fishing on Flathead Lake, enlisting anglers in solving the lake trout problem. A few fishing guides attended last Thursday’s meeting to express concern that a drastic drop in lake trout numbers would hurt their businesses.
CSKT’s management proposals would cost between $500,000 and $1 million.
Germaine White, a tribal information and education specialist, says implementing a new management plan is about valuing the tribes’ history. “We’re an ecotone people,” she said, having lived between the great salmon runs to the west and bison herds to the east. “We don’t have a story of a starvation winter,” she added, explaining that the tribes historically balanced times of scarcity and abundance by relying on multiple food sources, bull trout being one of them.
White and Hansen say that legacy and recreation can both be preserved.
“It is no time to wait for the problem to get worse,” Hansen said during the meeting. “It’s time to do something proactive.”
Science Source is a project of the University of Montana School of Journalism.