Fishing Lake Superior this fall? Report marked splake to the DNR

The fall fishing season for splake is coming soon! Splake fishing in the fall on Lake Superior is an experience unmatched anywhere else in the state. As temperatures drop and leaves begin to change, the splake bite picks up as the fish move nearshore. Splake — a hybrid cross between lake trout and brook trout — have been stocked in Lake Superior most years since 1971, with annual stocking since 1990. Marked splake have been stocked in Lake Superior since 2021 as part of an evaluation study. At the Marquette State Fish Hatchery, staff from the Michigan Department of Natural Resources’ Lake Superior and Northern Lake Michigan management units, as well as staff from the Tribal Coordination Unit, put in long hours carefully marking the splake by hand. Splake are given a unique mark by clipping (and removing) part of either one or two fins. The fish are anesthetized during this process.

These fish are then stocked in the spring at three Lake Superior ports: Copper Harbor, Keweenaw Bay and Munising Bay. The goal is to create nearshore fishing opportunities in the smaller bays of Lake Superior, where some fisheries are available year-round.

The evaluation study will be conducted through 2030. It is designed to help fisheries managers understand the percentage of stocked fish caught by anglers, the home range of splake, and metrics such as harvest rates and size at harvest by year and location.

“Early reporting from anglers has shown that splake remain relatively close to their stocking location and provide a fishery nearshore that is easily accessible with small boats or shore casting during open water periods on Lake Superior,” said Cory Kovacs, a DNR fisheries biologist for the Lake Superior Management Unit. “Splake are also readily available through the ice during winter fishing months.”

Identifying marked fish

Because they’re genetically tied to both lake trout and brook trout, splake look like either of the parent species, making them difficult to distinguish. Fisheries managers have also learned that identifying the correct fin clip on splake can be difficult to do while fishing, which poses a challenge for collecting data for the evaluation study. If you catch a splake, inspect it for missing fins or a clipped jawbone, indicating that the fish has been “marked.” Some clipped fins can be misshapen or missing, or appear abnormal. When looking for clipped fins on your fish, pay particular attention to the right and left pectoral fins, the right and left ventral (pelvic) fins, and the adipose fin — the small, fleshy fin found to the rear of the dorsal fin but in front of the caudal (tail) fin and found on only a few fish, including trout, salmon and catfish.

Reporting marked fish

Report marked fish through the DNR’s Eyes in the Field app to provide information such as species, length, weight, sex, and date and location caught, or by contacting a local DNR fisheries office.

Anglers also can report marked splake to DNR creel staff stationed at various ports along the Lake Superior shoreline through the end of October. Creel staff can help to correctly identify the fish, distinguish clipped fins on fish and record angler trip data.

Other natural resources agencies mark a variety of fish species for different evaluation purposes. For information on fish marking in Michigan, visit Michigan.gov/TaggedFish.

Note to editors: Accompanying photos are available below for download. Caption information follows.

• Lake Superior splake — A large splake caught in Copper Harbor during the winter months.
• Marked splake — A splake that has had its right pectoral fin clipped and removed. Marked splake may have clips on one or two fins.
• Fish fins illustration