Restoring Fish Habitat

Projects in the St. Clair–Detroit River System

Michigan Sea Grant was involved in a series of projects designed to restore fish spawning habitat for lake sturgeon, walleye and other native fish. 

  • Fort Wayne Reef Project. In 2015, the restoration team established a 50 x 50 foot test reef offshore from the historic Fort Wayne park in the Detroit River. Initial test reef results indicated the site is suitable for a larger restoration project so the team has finalized plans for a 4 acre reef and construction has been completed in June 2018. 
  • Fort Wayne Fact Sheet (PDF)

For more information about completed reef projects, see: Past Projects

Returning Sturgeon to the Detroit River

UM News, January 2017. University of Michigan researchers are part of a multi-institution team working to restore lake sturgeon, which were once common in the Great Lakes. Watch more videos.

The Need for Restoration

Many fish seek out rocky areas in fast-flowing currents in order to deposit their eggs during spawning season. However, many of the natural limestone reefs and rocky areas were destroyed in the Detroit and St. Clair rivers when shipping channels were constructed. Similar spawning areas in tributary rivers were made inaccessible as a result of dams or were damaged by development and sedimentation.

Despite massive population declines, the waterways connecting Lake Huron and Lake Erie continue to support the largest remaining population of lake sturgeon in the Great Lakes. Restoration efforts in these rivers could help rebuild native fish communities throughout the Great Lakes region.

Learning to Build Reefs

Many scientists believe that the recovery of lake sturgeon is hindered by a lack of accessible, high-quality habitat, including rocky habitat needed to successfully incubate fish eggs. The remediation plans for the St. Clair and Detroit rivers call for the construction of spawning reefs to compensate for the habitat lost historically and help rebuild degraded fish populations. However, creating more spawning habitat is not a straightforward process.

The location and design of spawning reef projects are based on studies of fish populations, models of river dynamics and lessons learned from completed projects. Three experimental reefs were built between 2004 and 2013 in the St. Clair and Detroit rivers, and each has led to important lessons that are being applied to upcoming projects.

Before designing a reef project, scientists study a proposed location to determine if conditions are favorable for restoration. After a reef is constructed, the team monitors fish activity and the number and types of fish eggs and larvae to evaluate whether the reefs are promoting successful reproduction of desired fish species. This research will assist future restoration efforts and help remediate Beneficial Use Impairments in the St. Clair and Detroit rivers, as outlined by the Area of Concern program and the U.S. Canada Great Lakes Water Quality Agreement Act.

Project Funding

The development of spawning reef projects has been supported through numerous grants, gifts and matching contributions. In addition to in-kind support from partner agencies, funding for reef restoration projects was provided by: the Great Lakes Restoration Initiative, National Oceanic and Atmospheric Administration, Sustain Our Great Lakes, U.S. Fish and Wildlife Service Coastal Program, Great Lakes Fishery Trust, Michigan Coastal Zone Management, Environment Canada, Canada-Ontario Agreement, Ontario Ministry of Natural Resources, BASF, DTE Energy, and Michigan Wildlife Conservancy.


Featured Publications

Reef Projects Lessons Learned-cover