Michigan DNR: Saving sturgeon – the ‘megafauna’ of Michigan’s fish world

Lake sturgeon are considered one of Michigan’s most historically and
culturally significant fish species, and a new rehabilitation strategy aims
to protect them well into the future. (Michigan DNR)
Author's note: This is another installment in the Showcasing the DNR series, produced by the Michigan Department of natural Resources.

First they were reviled. Next they were exploited. Then they were ignored.

Now, they’re almost revered. The status of lake sturgeon has changed dramatically in Michigan.

In the late 1800s, lake sturgeon were considered a nuisance by commercial fishermen, said Department of Natural Resources fisheries biologist David Caroffino, who co-edited a revised statewide recovery plan for Michigan’s sturgeon populations.

“Can you imagine? You’re trying to catch a 5-pound whitefish and you get a 100-pound sturgeon in your net,” he asked. “The sturgeon destroyed their nets.”

There are tales of sturgeon being stacked like cordwood and burned, just to be rid of them. Then, not many years later, a market developed for sturgeon, both for table fare and for their roe for caviar production. Sturgeon became a valuable commodity.

“People were harvesting millions and millions of pounds out of the Great Lakes,” Caroffino said. “Populations were decimated. They disappeared.”

Overharvest was just one of the problems. Widespread habitat destruction – siltation from the logging era and the building of dams in prime spawning habitat – reduced natural reproduction to a minimum.

Sturgeon fell victim to a double-edged sword.

Remnant populations “were largely ignored for much of the 20th century,” Caroffino said.

Although sturgeon were out of mind for most of the century, they were never totally out of sight. Because of their natural history – traveling up rivers to spawn, often in water no more than a few feet deep – sturgeon are readily observable, at least for a short period of time.

“In the last 30 years, we have been in a period of rehabilitation,” Caroffino said. “In the spring, there they are – and nothing else looks like a sturgeon. Sturgeon are the charismatic megafauna of Michigan’s fish world. They are our pinnacle species. They are the largest, the longest-lived, most unique-looking of our fish.”

Fisheries managers have identified 24 lake sturgeon populations in Michigan waters, only three of which are considered abundant enough to allow harvest. The state’s rehabilitation plan features five components:

  • Minimize the harvest;
  • Improve spawning habitat or access to that habitat;
  • Supplement populations unable to sustain themselves by stocking;
  • Suppress sea lamprey predation; and
  • Engage the public to help.
Michigan’s most prominent sturgeon population is in Black Lake (near Onaway, in the northern Lower Peninsula). The fish were cut off from the Great Lakes by dam construction, but managed to hang on in the lake, where they provide a popular spear-fishery through the ice.

As the harvest fell over the years, fisheries managers tightened up winter fishing regulations. The five-day fishery was changed to a quota system. (Last year, the season lasted just a couple of hours before the quota was reached.)

Ed Baker, a DNR fisheries research biologist
involved in lake sturgeon rehabilitation efforts,
shows off juvenile fish at a rearing facility on a
northern Lake Michigan tributary.(Michigan DNR)
Soon, an army of volunteers – calling themselves Sturgeon for Tomorrow – materialized, promising to do what they could to help rehabilitate the species.

Sturgeon for Tomorrow organized patrols along the Black River to prevent poachers from taking spawning adults and helped raise funds to build a nursery facility on the river. Now, not only is the adult population more protected, but a streamside rearing facility is producing fish to restock Black Lake, as well as nearby Burt and Mullet lakes.

The DNR maintains streamside facilities on several Great Lakes tributaries, too.

Ed Baker, a DNR research biologist working out of Marquette, oversees portable rearing facilities on the Cedar River and Whitefish River on Lake Michigan’s north shore. Both are in their sixth year of production, which has been sort of hit-or-miss.

Both Upper Peninsula facilities utilize eggs taken from mature sturgeon in nearby rivers to produce fall fingerlings for stocking. Production has varied from no fish in either facility in 2008, to almost 5,000 sturgeon between them in 2010. (In most years, production has been well below 2010 levels.)

“It’s still a learning process,” Baker said. “But fish that we have stocked from these streamside hatcheries have been out wandering around Lake Michigan for a few years now. We’ve been tagging these fish, and we’re already recapturing these fish in Lake Michigan.”

In September, DNR crews surveying for walleye in Big Bay de Noc netted a young sturgeon that had been stocked in Wisconsin’s Milwaukee River.

“We’ve had an on-and-off effort on the Ontonagon River, too, that has not had good success,” Baker said. “Hopefully, next year, we’ll have a streamside U.S. Fish and Wildlife Service facility there near the outlet of Lake Gogebic.”

In the Lower Peninsula, the DNR runs a streamside rearing facility at New Richmond on the Kalamazoo River, which is co-owned by the DNR and the Fish and Wildlife Service. The facility, which went online in 2011, raises sturgeon from either naturally fertilized eggs or naturally produced larvae that are collected in egg traps or drift nets in the river.

Local rearing facilities are critical to the future sustainability of
Michigan’s lake sturgeon populations. Dr. Kim Scribner of Michigan
State University assists in statewide efforts to protect this unique species.
(Michigan DNR photo)
In 2011, the facility produced 106 sturgeon to stock in the river.

“This year was a total loss,” said Kregg Smith, the DNR biologist in charge of the project. “We only captured 30 larvae, which is not enough to operate the streamside rearing facility.”

Rearing sturgeon for stocking has proven to be a difficult, uncertain and expensive proposition, but it is the only practical way to rebuild sturgeon populations, Caroffino said.

“Habitat work is very expensive, difficult to accomplish, and has potential impacts on other species,” he said. “If we start ripping out dams to provide more spawning access, we’ll be increasing sea lamprey spawning habitat, too.”

Caroffino remains optimistic about the species’ future.

“I expect a new-found commitment to lake sturgeon,” he said. “The scientific community knows a lot more about sturgeon now than we did, so we can refine our strategy based on our current knowledge. We’ve been so focused on revising our strategy we haven’t really discussed anything else over the last four years. Now we’ve got to try to implement the strategy.”

For more information – including the statewide recovery plan (Lake Sturgeon Rehabilitation Strategy) mentioned earlier in this article – visit www.michigan.gov/sturgeon. This website also provides a variety of information on lake sturgeon including background and history; a listing of partners and resources; a collection of news, videos and photos; and a section explaining to visitors how they can help protect the species.