Lake Superior Lake Trout Recovery - A Remarkable Journey

Green Bay Fish and Wildlife Conservation Office Fish Biologist Kevin Pankow displays a lake trout captured gill netting near Isle Royale on Lake Superior, June 2, 2014. Image credit: Mike Seider/USFWS.

Two recent stories from the fall of 2024 declared that Lake Trout in Lake Superior are fully recovered. 

That’s good news because Lake Trout have had a rough time for decades. 

“It has taken over 60 years to rehabilitate Lake Trout in Lake Superior,“ said Don Schreiner, Minnesota Sea Grant fisheries specialist, retired Minnesota Department of Natural Resources (MNDNR) Lake Superior Fisheries Supervisor and former member of the Great Lakes Fishery Commission’s (GLFC) Sea Lamprey Control Board. 

Schreiner was also the principal author of the MNDNR Special Publication "Lake Trout Rehabilitation in the Minnesota Waters of Lake Superior, 1962-2014," which synthesized efforts to rehabilitate Lake Trout (Salvelinus namaycush) in the Minnesota waters of Lake Superior. 

Lake Trout by the Decades 

Prior to the 1940s, Lake Superior was considered one of the premier Lake Trout fisheries in the world and supported a large commercial fishery. From the late 1800s to the 1940s, Lake Trout were distributed to markets throughout the metropolitan areas of the eastern and central United States. Lake Trout were also a native apex or keystone predator in Lake Superior and supported a growing recreational fishery until the mid-1950s. 

Beginning in the 1940s, the Lake Trout population began to decline from commercial overfishing. By the 1950s, non-native Sea Lamprey, decreased the abundance of Lake Trout even further. Sea Lamprey are a destructive parasite that attacks Lake Trout and that made their way to Lake Superior through the Welland Canal, which connects Lake Ontario and Lake Erie, circumventing Niagara Falls. 

The harvest of Lake Trout in Lake Superior declined so dramatically by the early 1960s that fish management agencies severely restricted the Lake Trout harvest from both the commercial and sport fishery in an effort to protect the remaining populations. At the same time, the number of commercial operators in Lake Superior declined. 

Starting in the mid-1960s reestablishment of Lake Trout populations in Lake Superior became a major goal of the Great lakes Fishery Commission and Lake Superior fish management agencies. Successful Sea Lamprey control, restrictive harvest regulations, and Lake Trout stocking all contributed to rehabilitation of Lake Trout in Lake Superior in the intervening 60 years. 

Full recovery of Lake Superior Lake Trout was officially declared a success in the fall of 2024. 

Highlights from the Great Lakes Fishery Commission and Minneapolis Star Tribune 

The Great Lakes Fishery Commission published a news release in late November 2024, that highlighted the proclamation by the Lake Superior Committee that Lake Superior Lake Trout have been fully restored. 

The Lake Superior Committee is coordinated by the Great Lakes Fishery Commission, and consists of fishery managers from the three Great Lakes States which border Lake Superior (Minn., Wisc., and Mich.), the Province of Ontario, and the U.S. tribes represented by the 1854 Treaty Authority, Chippewa-Ottawa Resource Authority (CORA), Great Lakes Indian Fish and Wildlife Commission (GLIFWC), and the Red Cliff Band of Lake Superior Chippewa Indians. 

Lake Trout rehabilitation would not have been possible without the sacrifices of Lake Superior commercial netters and anglers, along with the dedication of provincial, state and tribal fish management agencies. The Sea Lamprey control program facilitated by the GLFC and carried out by the U.S. Fish and Wildlife Service, and Fisheries and Oceans Canada also played a critical role. 

“Rehabilitating Lake Trout in the world’s largest freshwater lake did not happen overnight; it required an unwavering commitment to a shared vision across multiple generations of fishery managers from Indigenous, provincial, state, and federal agencies. It is undoubtedly one of the most successful stories of native species restoration in the world. Lucky for us, we have a front row seat,” Ethan Baker, chair of the Great Lakes Fishery Commission was quoted saying.

The Minneapolis Star Tribune story, published December 7, 2024, states that since Lake Trout in Lake Superior have recovered, the Minnesota Department of Natural Resources (MNDNR) began sampling a small number of Lake Trout (18 females and 18 males) to use as a source of eggs for rearing young Lake Trout to be stocked in inland lakes. 

“It’s kind of a good story to tell. We busted our butts to rehabilitate lake trout in Lake Superior and now the population is doing so well we are using those adult fish for inland stocking programs,” Cory Goldsworthy, MNDNR Lake Superior Fisheries Supervisor was quoted as saying.

This new approach of collecting wild Lake Trout from Lake Superior to use as broodstock could potentially save significant amounts of money since captive broodstock would no longer need to be held in hatchery facilities on a year-round basis. In many cases fish derived from wild sources survive better, grow better, and can reproduce more successfully in the wild than fish from captive broodstock because they undergo minimal domestication in the hatchery. 

“Two management activities that will  sustain the tremendous progress achieved in Lake Trout rehabilitation, is continued funding for Sea Lamprey control efforts and the implementation of conservative harvest regulations for both the sport and commercial fisheries,” said Schreiner. 

Sea Grant's Role 

The GLFC news release and the Minneapolis Star Tribune story both describe evidence that Lake Trout rehabilitation in Lake Superior is a major success story in fisheries management. 

“Rehabilitation of any fish population is a rare achievement in fisheries management and doing so in the largest lake in the world is a huge accomplishment,” said Schreiner. “Sea Grant has a major focus area on sustainable fisheries and one way we help to sustain fisheries is to provide and support sound science and share appropriate information that helps people make informed decisions on how best to protect our fisheries resources.”

Resources
  1. Minneapolis Star Tribune story 
  2. Great Lakes Fishery Commission news release 
  3. Lake Trout Rehabilitation in the Minnesota Waters of Lake Superior, 1962-2014 (MNDRN) 
  4. A Superior Success Story (MNDNR)
  5. Fisheries Management Plan for the Minnesota Waters of Lake Superior (MNDNR) 
  6. MNDNR Lake Superior Area
CONTACT: 

Don Schreiner, Fisheries Specialist, Minnesota Sea Grant, University of Minnesota and University of Minnesota Duluth, [email protected]

Marie Thoms, Communications Director, Minnesota Sea Grant, University of Minnesota and University of Minnesota Duluth, [email protected].