The Lake Sturgeon Have Arrived!

Sturgeon Reproduction Documented at Fighting Island Reef!

Sturgeon Fry from Fighting Island, about 5 weeks after hatch- Image by Jeff Allen, USGS-GLSC

Lake sturgeon have spawned four times on the reef constructed last year at the head of Fighting Island in the Detroit River! This is the first time in 30 years that spawning by lake sturgeon, a threatened species in both Michigan and Ontario, has been confirmed in the Canadian waters of the Detroit River. The new spawning reef, constructed at Fighting Island in October, 2008, was celebrated as the first Canada-U.S. funded fish habitat restoration project in the Great Lakes. The strong partnership between our nations and the dedication of everyone involved in protecting our shared natural resources made this project a reality. The fact that lake sturgeon, an indicator of ecosystem health, are utilizing the reef, provides scientific evidence that this restoration project was a success and further validates the binational pollution prevention and control efforts implemented through the water quality agreements crafted in the early 1970s (e.g., the U.S.-Canada Great Lakes Water Quality Agreement).

Sturgeon Fry from Fighting Island, about 5 days after hatch- Image by Jeff Allen, USGS-GLSC

The lake sturgeon population in the Detroit River is estimated to be about 1% of its former abundance. Over the past century, fish populations in the Detroit River have been greatly reduced by channelization, loss of coastal wetlands, filling/armoring of shorelines, water pollution, and dredging of the limestone bedrock that served as spawning habitat for lake sturgeon and other native fish species. Scientists determined, based on three previous reef projects undertaken in both Canadian and U.S. waters, that they could build new spawning habitat using various types of materials, such as broken limestone rock, to enhance reproduction of lake sturgeon and other fish. The finding of fertilized lake sturgeon eggs at Fighting Island indicates that this restoration strategy is yielding very positive ecosystem results, and that this small, remnant population of native lake sturgeon may one day be restored to a higher level of abundance in the Detroit River.

Adult Sturgeon Captured at Fighting Island - Image by
Dr. Bruce Manny, USGS-GLSC

Walleye and lake whitefish have also spawned on the reef, demonstrating that the constructed spawning habitat is enhancing populations of these high-value fish as well!

Other exciting news at the Fighting Island reef was the discovery of several Northern madtom, a fish that is endangered in Michigan and Ontario and never before confirmed in the mid-reaches of the Detroit River. Northern madtom were also discovered on the spawning reef constructed at Belle Isle in 2004, indicating that this type of habitat restoration is of value for sustaining threatened and endangered native fish populations. It is critical that scientists continue to monitor the reef for at least 2 years to document use of the spawning habitat by other valuable native fish.

The construction of the lake sturgeon spawning reef at Fighting Island exemplifies the spirit of binational collaboration, partnership and stewardship of our shared resources. The success of this fish habitat restoration strategy will strengthen and improve the fishery in the Detroit River, the Huron-Erie Corridor, and ultimately the entire Great Lakes!