What’s the deal with leaping fish in the Milwaukee River?
The Milwaukee River is a main artery of the watershed that bears its name.
A Bubbler Talk question asker wondered, "What kinds of fish leap in the Milwaukee River? How are those fish populations doing?"
I met Laura Schmidt to find out.
“I’m a fisheries biologist with the Wisconsin Department of Natural Resources. We’re standing along Estabrook Park near the former Estabrook Dam,” she says.
We’re upstream from the river’s urbanized, channelized downtown Milwaukee self and entering the more natural version of its 100 meandering miles.
“If you just want to watch the fish jumping, this is a good spot right here, trying to get above the little falls here in Estabrook,” Schmidt says.
Fish leaping is a seasonal phenomenon.
“In spring, we’ll see rainbow trout running up the river for their spawning time. And they’re impressive swimmers, they have a strong jumping ability. They can actually make their way all the way up to the Bridge Street Dam in Grafton,” Schmidt explains.
Autumn signals spawning season for both chinook and coho salmon, and sometimes brown trout.
To determine how those fish populations are doing, Schmidt says she and her colleagues monitor in the river and in Lake Michigan because when they’re not spawning, those fish live in the great lake.
Turns out, the Wisconsin DNR along with its Indiana, Illinois and Michigan counterparts stock all of the leaping species.
None were native to the basin, but Schmidt says they've long shared the lake's waters.
“The chinook and coho salmon in particularly were originally stocked to control the alewife,” she says. Salmon feasted on the invasive fish. “And the sport fishery took off from there. In fact, we do see those species naturally reproducing on the Michigan side of Lake Michigan. Their streams are a little more conducive to that."
DNR biologists see far less success in the Milwaukee River and its tributaries because water temperatures are higher and sediment often smothers the eggs.
That doesn’t keep the spawners from trying.
For salmon, spawning is literally a once in a lifetime experience. After it accomplishes its spawning mission, the fish dies.
“But the rainbow and brown trout can spawn multiple times, so they will migrate up the river during spawning time and then make their way back out to Lake Michigan and live to see another day,” Schmidt says.
There’s more to the Milwaukee River scene than the drama of visiting spawners, Schmidt says species native to the river are faring well.
Anglers are allowed to fish for both river dwelling and visiting fish. “You can keep five fish and it can be any mixture of fish and it’s a fishery that’s open year round,” Schmidt says.
There is one fish anglers may not go after. For over a decade the DNR and other partners have been working to reestablish Lake Sturgeon.
“They were extirpated years ago, but we’ve been stocking them in the Milwaukee River for 16 years, so we’re beginning to see some adults return,” Schmidt says.
I met Joe Davies and Pete Nicoloff enjoying the river, further upstream beyond the Thiensville dam where a newly improved fish passage was recently completed.
“Now there’s some nice resting pools, some nice runs. They made the pools deeper [to] keep the fish safer. There might be some fish hanging out there now, but you can see salmon and trout and stuff resting. It’s really cool,” Nicoloff says.
They aren’t just avid anglers, they guide people on fishing expeditions. Davies says they stick to the catch and release approach.
“Yeah, you just do your best to let ‘em go and let ‘em grow because that 15-inch fish you let go — [in] two to three years’ time — is gonna be a trophy fish for somebody and have reproduced during those three year period of time,” he says.
Davies, who spent years fishing around the world, says the Milwaukee River experience can’t be beat.
“Having grown up here and then spending about 20 years away, the Milwaukee River had this reputation for not being the cleanest waterway out there, [but] there’s been some groups that have done unbelievable work. It gets to the point, you go far enough north, the water can get so clear the fishing becomes quite difficult,” Davies explains with a laugh. “Because the fish see you.”
Nicoloff says whether you return the catch to the river or take it home, the river is for everyone.
“The same species are available right in Milwaukee. A kid can ride a bike from a backyard in Glendale to Kletzsch Park, North Avenue Bridge. Those sections of the river hold the same pike and smallmouth bass we target up here. They’re just as plentiful down there. They’re accessible to anybody that can get there via public transportation or walk or ride your bike,” Nicoloff says.
Turns out, the leaping fish question introduced us to more than the life cycle of salmon and the thrill of catching a smallmouth bass.
Take it from biologist Laura Schmidt: “You know, fish are resilient and they seem to find a way to live in many different conditions. I think that’s really cool.”