Reestablishing Sturgeon in Milwaukee Waters Takes Time

Sep 30, 2016

Saturday one thousand baby sturgeon will be released along the shore of Lake Michigan. The event is a part of a 25 year partnership between Riveredge Nature Center and the Wisconsin DNR.

The ancient fish was once plentiful here, but by the turn of the last century its numbers had plummeted.

DNR fisheries technicians Tom Burzynski (left) and Dave Schindelholz on route to setting nets on Lake Michigan.
Credit Susan Bence

“The commercial fisherman thought they were trash and they’d just bring them up on shore and burn them, and then they found out lining of the swim bladder can be used to clarify oils and jellies and such, so they decided to fish them,” says DNR fisheries technician Tom Burzynski.

What perhaps those fishermen didn’t appreciate, is the fact that sturgeon can live 100 years. In fact, Burzynski says, it takes them a long time to even reach spawning age.

“You’re talking about a fish that takes 25 years minimum to have another generation,” Burzynski says.

So bringing the species back to life takes time - and comes with challenges.

“They produce a lot of eggs but survival is not necessarily that high. There’s going to be egg mortality,” Burzynski says.

Then there’s the challenge of returning the lake sturgeon to their native spawning passageway – the Milwaukee River.

Burzynski says when crews removed the North Avenue Dam in the city nearly 20 years ago, biologists started to dream of bringing spawning back to the river.

In 2006, the DNR struck up partnership with Riveredge Nature Center. It’s located 30 miles upstream of Milwaukee.

To find eggs, the agency had to travel to northeastern Wisconsin where sturgeon spawning is going gangbusters on the Wolf River.

Riveredge volunteer at work inside sturgeon rearing trailer.
Credit Eric Larsen

Back at the nature center, volunteers began tending the eggs in a trailer and circulating Milwaukee River water through the tanks.

“Riveredge Nature Center has been tremendous. For us to run up to Riveredge or wherever that far north every day. We have volunteers that are there seven days a week and some of them have been there since the beginning,” Burzynski says.

The hope has been, that adult sturgeon will come to remember the water and swim upstream in it, to spawn.

Fellow fisheries technician Dave Schindelholz releases net.
Credit Susan Bence

In the meantime, Burzynski has been checking on the survival of sturgeon released into Lake Michigan.

He heads outside the breakwater and sets nets, hoping to find a few juveniles.

“Once they get to to a certain size, I mean if they get to be 12 or 14 inches long, there’s not a lot that’s going to eat them. There’s about 85 percent survival,” Burzynski says.

The next morning, rain and wind buffet the boat as Burzynski struggles to pull in the net. The lousy conditions don’t dampen the spirit of Technician Jeff Zinuticz because among the whitefish and suckers entangled in the net, a juvenile sturgeon rolls in.

Weighing the young sturgeon.
Credit Susan Bence

He’s jubilant as he weighs and measures the fish. Practically 22 inches long and about 8 ½ inches around.

Zinuticz snips the tiniest bit of fin for genetic sampling – before tossing the sturgeon back home.

Soon two more sturgeon come aboard – one bearing the tag of the Riveredge Nature Center. The little guys are 3 and 4 years old.

Tom Burzynski dreams of the first batch of adult sturgeon plowing up the Milwaukee River to spawn – but says by that time he’ll probably be watching from the sidelines.

“In a few years, 2026, we might be looking at the females making the trip, we’ll see. We’ll just tell the young kids what to do,” Burzynski says.

Fingerling sturgeon await their release into Lake Michigan.
Credit Carly Hintz