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Boreal Community Media

Rare fish on rebound in northern Lake Michigan as pros, cons of stocking debated

Mar 28, 2018 06:49AM ● By Editor


The cisco (aka lake herring, Coregonus artedi) was one of the most abundant fish in Lake Michigan before unregulated commercial fishing, invasive species, and habitat degradation took their toll. By the mid-1960s, cisco were nearly wiped out. Most of their deepwater cousins also disappeared from the lake. Six out of seven native deepwater ciscoes are no longer found in Lake Michigan. The only deepwater cisco that still survives in Lake Michigan is the Bloater (Coregonus hoyi).

To confuse matters, not all cisco (Coregonus artedi) look and act the same. According to a recent monograph, there are different “minor forms” of the cisco species. Body depth and mouth shape vary somewhat from one minor form to the next, but the reasons for this variability are poorly understood. It comes down to a classic question of “nature vs. nurture.”  At this point, we are unsure if different minor forms of cisco are different because of their genetic code (DNA) or because of the influence of their changing environment and ecological niche.

After all, Lake Michigan has changed dramatically since cisco crashed in the late 1950s and early 1960s. At that time, exotic alewife were taking over and native predators (lake trout) had been wiped out by invasive sea lamprey. With no predators to keep them in check, the small, silvery alewife boomed. Another invader, rainbow smelt, was also in the mix. Cisco populations suffered as alewife and rainbow smelt likely competed for food resources and preyed on the tiny pelagic cisco larvae.

Now Lake Michigan cisco are making a comeback. Populations are on the rise in Grand Traverse Bay and surrounding areas. Anglers are catching more cisco every year, and they are beginning to show up in unexpected places. Cisco have been present in seasonally fishable numbers in Charlevoix, Portage Lake, and Manistee in recent years. Occasional catches have been reported even farther south.

These cisco are not behaving like historic Lake Michigan cisco, though. Most notably, their diet now includes other fish such as alewife and round goby. Historically, Lake Michigan cisco mostly ate zooplankton and other small invertebrates. Cisco in present-day Lake Superior and Lake Ontario do the same, but for some reason our recovering Lake Michigan cisco population is different.

This has sparked an active debate among biologists and fishery managers over the past several years, and Great Lakes anglers and conservationists are now beginning to consider the issue, as well. At the recent Ludington Regional Fisheries Workshop hosted by Michigan Sea Grant, Chuck Bronte of the U.S. Fish & Wildlife Service gave an overview of the issue and management options that are now being considered. Possible options included stocking cisco in Lake Michigan using spawners from Lake Superior, Lake Michigan, or multiple sources. 

Jory Jonas of Michigan DNR also presented, providing an overview of the current status of Lake Michigan cisco. She highlighted research on cisco diet, habitat, and harvest trends along with pointing out how much we have to learn about these fascinating fish.

Anglers and Great Lakes conservationists in the audience at Ludington were given a chance to make statements regarding their thoughts on cisco. In case you missed that opportunity, cisco will be on the agenda again at the free Southern Lake Michigan Regional Fisheries Workshop, held at 7 p.m. April 19, 2018 at the Moose Lodge, 1025 Wells St., (see agenda,no registration necessary).

At the workshop, organizations and individuals will be given the opportunity to read prepared statements expressing their views, suggestions, or questions on cisco before a question and answer session with cisco experts.

The future for cisco in Lake Michigan is looking much brighter than it did a decade ago. Remnant fish are successfully reproducing, researchers are devoting time and energy to enhance our understanding, and managers are carefully weighing whether to take a more active role in restoration. Great Lakes stakeholders are also learning more about how important this fish once was to Lake Michigan’s ecology and fisheries.

The cisco is an amazingly adaptable, and useful, fish. It can feed on zooplankton, bottom-dwelling invertebrates, emerging insects, or small fish. It can be an excellent food source for a variety of predatory gamefish and also grows large enough to interest recreational anglers and commercial fishers. Cisco can be caught by ice fishing, fly casting, jigging, or trolling. Fresh cisco makes a memorable meal when baked, grilled, or sautéed. Commercial fishers often market smoked cisco, and Lake Superior cisco eggs (roe) are exported to Scandinavian countries where they are considered a delicacy.

Above all, the cisco is versatile. It can be many different things in many different circumstances. Attend the workshop on April 19 to learn more about the complex history and ecology of this unique fish.

Michigan Sea Grant helps to foster economic growth and protect Michigan’s coastal, Great Lakes resources through education, research and outreach. A collaborative effort of the University of Michigan and Michigan State University and its MSU Extension, Michigan Sea Grant is part of the NOAA-National Sea Grant network of 33 university-based programs.

This article was published by Michigan State University Extension. For more information, visit http://www.msue.msu.edu. To have a digest of information delivered straight to your email inbox, visit http://www.msue.msu.edu/newsletters. To contact an expert in your area, visit http://expert.msue.msu.edu, or call 888-MSUE4MI (888-678-3464).

Jory Jonas, Fisheries Research Biology Specialist with Michigan Department of Natural Resources, discusses the status of recovering cisco populations in Lake Michigan. She presents lessons learned and those yet to be learned.

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