Late-night lake sturgeon: GRPM continues surveys on the Grand River

GRAND RAPIDS, Mich. — Lake sturgeon know a thing or two about survival because they've seen a thing or two over their 150-million year existence.

In September, the Grand Rapids Public Museum and its partners returned to the Grand River for their annual lake sturgeon survey, looking to see if the waterway can sustain a population, decades after the prehistoric fish nearly went extinct.

"They've been around for a very long time, since the time of the dinosaurs," said Dr. Stephanie Ogren, the museum's vice president of science and education, calling lake sturgeon an "indicator" species: "They can tell us a lot about the health of an ecosystem."

A dry month allowed for favorable fishing. Two to four times a week in September, Ogren and other researchers floated out on a pair of boats at dusk.

When darkness fell, they shined floodlights into shallow water, searching for the silhouette of a juvenile lake sturgeon at a dozen different "index sites" scattered between Grand Rapids and Grand Haven.

"Anytime you can see a threatened species, it's a good night," said Ogren, estimating an 80% catch rate.

If the crew nets a lake sturgeon, they clip its fin to collect a genetic sample, helping piece together a genetic "signature" of all the lake sturgeon living in the Grand River, one that can be compared to populations living in other Michigan bodies of water.

Then, the fish are returned to the wild.

While years worth of data is still needed to make any real determinations about the fish and the river, Ogren is seeing and catching lake sturgeon, something she couldn't say in the past.

"Really understanding the Grand River population and all the other populations throughout the Great Lakes is really important," she said.

The surveys will continue into October.