Lake Trout: Wild Reproduction Success

There’s a change afoot in Lake Champlain’s celebrated lake trout fishery. For decades, the lake trout that Vermont anglers have been catching on Lake Champlain were stocked fish of hatchery origin, easily identifiable by a clipped (missing) fin. But over the past 10 years, lake trout have been turning up in surveys and in anglers’ nets with all fins intact — a sign that one of Lake Champlain’s top native sportfish is reproducing in the wild once again.

Lake trout and landlocked Atlantic salmon are two members of the salmonid family native to Lake Champlain. Lake trout are a long-lived species (over 25 years), that feed on small fish like rainbow smelt and alewife. Requiring cold, well oxygenated water typically found in the main lake portion of Lake Champlain, lake trout serve as an important indicator of overall ecosystem health.

By the early 20th century, habitat loss, declining water quality, and shoreline development eliminated lake trout from Lake Champlain. A stocking program was established in the 1950s with the goal of restoring a self-sustaining population, but there was little evidence of natural reproduction in the ensuing decades. The Lake Champlain lake trout fishery has been dependent on annual stocking ever since.

But fast-forward 60 years now, and we’re starting to see the fishery entering an exciting new phase! Assessments by University of Vermont and the Lake Champlain Fish and Wildlife Management Cooperative (LCFWMC) are finding an increasing proportion of unclipped (presumed wild) lake trout in recent population surveys.

For the fishery, the lake, and the anglers, supporting as much wild reproduction as possible is a win-win. With that goal in mind, the LCFWMC recently decided that if fish collection surveys found more than 15% of the lake trout less than 26 inches long had no fin clips (indicating wild origin), then stocking would be reduced. That threshold was passed in 2020, and the LCFWMC cut stocking numbers by 33%, going from a target of 82,000 to about 54,000 lake trout stocked annually, starting in 2022.

For anglers, this stocking reduction is good news. It allows fishery managers to make sure that wild trout are not in competition with stocked trout for food resources. And for the Lake Champlain ecosystem, the benefits are also impressive. Lake trout inhabit the deepest parts of the lake and play an important role in energy cycling in these deeper waters. This provides more ecological stability within these offshore zones and fosters a more diverse fish community.

The return of wild lake trout in Lake Champlain is a success story that anglers, biologists, and everyone who cares about the lake should celebrate! But the work isn’t over. Vermont Fish & Wildlife continues to monitor the population’s response to reduced stocking. Additional adjustments could be made in the future depending on the results of continued monitoring and assessment work. As always, the goal is a healthy fishery, a healthy lake, and a great experience for anglers.