Hide and Go Seek: the Lake Sturgeon Edition
By Margaret Hutton
Alpena Fish and Wildlife Conservation Office
For nearly 20 years, organizations have studied lake sturgeon in the Huron-Erie Corridor. Within the corridor, there are thought to be three main spawning populations: one in the Detroit River, one in lower St. Clair River, and the last in southern Lake Huron near Port Huron, Michigan.
While we understand that lake sturgeon are utilizing these locations within the corridor, little is known about where lake sturgeon travel before and after they spawn.
Lake sturgeon are a potamodromous species meaning, for a majority of their life, they live in the larger lakes but travel up streams and rivers to locations with rocky habitat to spawn.
Lake sturgeon do not spawn on an annual basis. Male lake sturgeon will only spawn every two to four years, while female lake sturgeon will wait four to seven years between spawning events.
Within this time frame, little is also known about the lake sturgeon’s life history. Previous tagging efforts, using external tags and Passive Integration Tags (PIT), have shown that lake sturgeon can travel great distances. Lake sturgeon caught and tagged in the corridor were recorded in areas as far as eastern Lake Erie and Green Bay, Wisconsin.
A new project funded by the Great Lakes Fishery Trust titled, “Lake Sturgeon Meta-Population Structure: Migration Pathways, Spawning Fidelity, and Survival in a Complex River-Lake Ecosystem,” is about to answer some of the questions regarding fish movement in the Huron-Erie Corridor.
U.S. Fish and Wildlife Service fish biologists from the Alpena Fish and Wildlife Conservation Office’s Waterford Substation, have partnered with the U.S. Geological Survey, Great Lakes Fishery Commission, Michigan Department of Natural Resources, and Ontario Ministry of Natural Resources in order to tag sexually mature, adult lake sturgeon in the corridor with acoustic transmitters.
The new transmitters will allow biologists to collect more continuous data compared to the external and PIT tags. With these transmitters, a fish does not have to be recaptured for the scientists to receive information.
To date, 160 adult lake sturgeon were implanted with transmitters by project partners. Lake sturgeon movements are currently being monitored using an acoustic telemetry array, with 77 receivers deployed within or in close proximity to the corridor. The lake sturgeon captured will still be tagged with external tags for recreational anglers to report information including length and location by calling the telephone number on the tag and providing the corresponding lake sturgeon fish number.
Preliminary movement results are consistent with previous theories that three spawning populations exist, however more data is needed to fully assess movement patterns of adults within this system. The results of this study will provide insight regarding potential spawning locations, seasonal movement patterns, and survival of this threatened fish species.