More than 20 years ago, a Green River angler reeled in a 50-pound lake trout from the depths of Flaming Gorge Reservoir.
It was 4 feet long and almost 3 feet around.
As impressive as that record is, fish over 40 pounds are more common than you’d think in the 91-mile tub straddling the border between Wyoming and Utah. Flaming Gorge is known for its trophy lake trout fishing that draws thousands of people from across the country.
But Robb Keith worries those big ones may eventually disappear.
“Our concern is that we won’t recruit new fish into that trophy size and eventually the fish that are trophy size right now will grow old and either die from old age or die from being hooked,” said Keith, the Green River fisheries supervisor for the Wyoming Game and Fish Department. “If you don’t have replacement fish and are not recruiting new individuals, that’s the concern.”
The solution might sound counterintuitive: Catch, keep and eat more small lake trout.
He explains it best: “We have a lot of small fish competing for a limited resource, and they’re not growing nearly as fast as they were 20 or 30 years ago. These fish are essentially stunting... There’s not enough forage out there to go around.”
As a result, Game and Fish proposed changing the lake trout regulations on Flaming Gorge to allow anglers to keep up to 12 fish each day instead of the current eight, and, more importantly, increase the number of fish an angler can have in possession from eight to 24. Anglers would still only be allowed to have one fish over 28 inches.
The public comment period for the changes ends June 4, and the Game and Fish Commission will vote on them at its meeting July 10 and 11 in Laramie.
In general, biologists want fish populations to follow a similar age and size trajectory. Quantities shrink as sizes and ages increase.
But Keith and other fisheries biologists in the Green River area realized lake trout on Flaming Gorge are following a different path. Numbers are staying high as the fish age, but they aren’t growing. Fish sizes are essentially hitting a wall.
After examining fish ear bones — which have rings showing age similar to trees — biologists found that in 1991, a 10-year-old lake trout was 33 inches long and weighed 15 pounds. In 2016, the same age averaged 24 inches and 4.5 pounds.
“There’s been a gradual decline in the trophy component in the reservoir and a gradual increase in the abundance of smaller fish,” Keith said.
That’s a problem both because of the impact on the trophy lake trout fishery, but also because medium-sized lake trout are voracious predators of other, smaller fish.
“These small fish less than 28 inches… eat other fish like kokanee and rainbows,” Keith said.
It’s particularly harmful in the winter when lake trout, which typically stay in the deeper, colder water, come closer to the surface to prey on baby kokanee and rainbow trout.
Fishermen spend more than 100,000 days on Flaming Gorge each year, and kokanee, rainbow and trophy lake trout are the three most popular species.
Anecdotes back up the research data. Utah angler Roger Schneidervin has been fishing Flaming Gorge for decades and has seen his catch rate for trophy lake trout dip. He has to work harder to catch bigger fish, and other anglers have told him a similar story.
The kokanee fishery, which he helped foster while he was working for Utah Wildlife Resources, concerns him even more.
“They’re taking longer to get to 28 inches or so, but they’re so long lived, so when they get to that moderate size they’re like a bunch of teenage boys that can’t get enough to eat,” Schneidervin said. “It’s hard to maintain a kokanee fishery when you’re depending on stocking.”
Rock Springs angler John Krmpotich has been fishing Flaming Gorge since 1976. He and a buddy once each had a 40-pound lake trout on their lines at the same time. But lately he’s been seeing more of the smaller lake trout.
He’s in favor of changing the regulations as long as Game and Fish continually monitors the population. He doesn’t want to risk harvesting too many lake trout.
“They’re talking about upping the limit and giving everyone a two-day limit in possession,” he said. “That’s a heck of a lot of fish.”
Biologists will be monitoring the trophy and smaller fish populations every year, Keith said. But he isn’t too worried about overharvest.
“There’s so many little lake trout out there even with angling pressure and getting anglers to harvest the chance of overfishing the fishery is really remote,” he said.
Plus, the average lake trout lives for 20 to 30 years.
Even with a regulation change, it could take some time for people to move out of the catch-and-release mindset and into a catch-and-keep one, Keith said. He and other fisheries managers are working on a public information campaign, beginning with reminding anglers how delicious the smaller lake trout are to eat.
“They are good table fare,” he said. “They’re high in the omega fatty acids, so they’re healthy and low in mercury because they’re not that big and old yet.”