Played a Part in Reef Project’s Success

The Takeaway: Scientists used vessel-traffic data and maps when considering the best test reef spot for boosting the vulnerable Lake Sturgeon population in Michigan.

A post-project study by the U.S. Geological Survey shows that artificial reefs in Michigan’s Detroit River and St. Clair River are expanding the spawning grounds for Lake Sturgeon, a species on the “threatened” list in 19 states that has been around since dinosaurs roamed the planet.’s Track Builder and National Viewer enabled Michigan Sea Grant researchers to “see” where vessel activity and propeller wash could threaten the success of the initial test reef or permanent reef. NOAA’s Digital Coast and the Bureau of Ocean Energy Management co-developed

The Track Builder uses automatic identification system vessel-traffic data, which is collected for maritime navigational safety by the U.S. Coast Guard and commercial vendors. The permanent reef will give the slow-to-mature Lake Sturgeon more spawning areas and the conditions needed to incubate and protect their young. It consists of loose limestone about two feet thick covering four acres of river bottom.

For years, researchers at the U.S. Geological Survey’s Great Lakes Science Center have monitored the Lake Sturgeons’ use of this artificial reef and five others in the Detroit River and St. Clair River. Lake Sturgeon eggs—which were not detected before reef construction—began appearing on all the reefs immediately after construction. In 2019, researchers detected Lake Sturgeon spawning on four of the six artificial reefs. Monitoring of these results continues.

Natural limestone reefs and rocky areas were once plentiful in the Detroit River, which feeds into Lake Erie, and the St. Clair River, which is downstream of Lake Huron. However, 20th-century gravel mining, and deep dredging for commercial ships, contributed to the destruction of spawning areas for millions of fish. The two rivers were listed as “Great Lakes Areas of Concern” under the Great Lakes Water Quality Agreement, making federal funds available for the construction of artificial spawning reefs since 2004. (2018/Updated 2021)

More Information: Digital Coast in Action

Partners: Michigan Sea Grant, NOAA Office for Coastal Management, U.S. Coast Guard, U.S. Department of the Interior’s Bureau of Ocean Energy Management, U.S. Geological Survey Great Lakes Science Center