Southwest Michigan Lakes' Unusual ResidentAgency: Natural Resources
Feb. 4, 2010
Recreational fishing has changed significantly over the course of Michigan's history. Fish that were originally native to waters thousands of miles away, such as Chinook salmon, now make up a major part of Michigan's sport fishery. Others that were once of primary importance to state anglers - such as grayling - are now a distant memory, having been fully extirpated from state waters. And still others, that were once of significant import, are now mere bit players in the recreational fishing narrative.
The cisco - commonly known as the lake herring - is one such example. Though some recreational fisheries still exist - most notably in the late summer in the St. Marys River - cisco were once an important recreational, as well as commercial, species in Michigan. Though most commonly associated with the Great Lakes, ciscos exist in a number of inland waters, too, where they provide limited recreational opportunities and the occasional, unusual by-catch to anglers who are seeking other species.
At one time, a small recreational gill net fishery existed in some inland lakes. Recreational anglers - who were required to buy a cisco stamp - were allowed to harvest fish for their personal use with what most consider commercial gear. And though that fishery is also part of Michigan's the past, cisco are not. The state did away with recreational gill netting many years ago.
Cisco still exist in a number of inland lakes and the Department of Natural Resources and Environment's Fisheries Division has been surveying lakes in some parts of the state, trying to determine where populations of the fish exist.
"We are verifying and updating work previously published by Dr. Carl Latta to determine where ciscoes still exist," explained Scott Hanshue, a fisheries biologist in the Southern Lake Michigan Management Unit, who has been surveying lakes in the southwest corner of the state, looking for ciscoes. "In some lakes they've been extirpated - Gull Lake, for example."
Hanshue, who works out of the DNR's Plainwell Operations Service Center, said the survey has two purposes - to find out where cisco populations exist and to, potentially, serve as brood stock lakes should the DNR ever decide to re-introduce the creatures into other waterways.
Members of the whitefish family, cisco inhabit cold, clear, well-oxygenated water. In the summer, they inhabit the thermocline - the area of the lake, often about 20 feet down, where the temperature breaks and well-oxygenated water tends to run out. Otherwise, they are usually deep, open-water denizens, except in the late fall, when they move inshore to shallow shoal areas to spawn.
That's when they are most susceptible to hook-and-line or gill-net fishing. And that's when Hanshue and his crew have been looking for them.
"We target them with gill-net surveys in the fall when they move to the spawning areas, just before ice-up," Hanshue said. "We try to hit two or three lakes a year, just trying to find out where they exist. We're really restricted by weather. We need to be there right before ice forms.
"Hopefully, we'll come up with some lakes that have large enough populations that they could serve as potential brook stock for rehabilitation purposes down the road."
Though most anglers commonly refer to them as herring, they are not. Herring are members of another family, with a salt-water component to it, and are more closely related to shad. Ciscoes are more delicate; because of their need for cold, well-oxygenated water, they are vulnerable to water-quality changes. And on that note, there's some good news; Hanshue and his crew have found cisco in some lakes that have become heavily developed in recent years. Nonetheless, cisco are considered a threatened species in Michigan, although it is legal to catch and keep them.
This fall, Hanshue et al surveyed three lakes, though they didn't get to spend as much time at it as they might have liked as ice-up came suddenly. Still, the results were relatively positive.
At Harwood Lake in Cass County, the fisheries crew netted a fair number of fish with very few net/days of effort.
"For the amount of effort we put in, there appears to be a good population at Harwood." Hanshue said. "We caught multiple-age classes and robust fish. They were up to 22 inches."
Often, Hanshue said, net surveys will yield fish of just one year-class. Biologists are not sure whether that indicates year-class failures or some other phenomenon.
"We don't know what that tells us," Hanshue said. "These things are notoriously hard to catch."
At Pleasant Lake in St. Joseph County, the crew turned up just one fish. But on a positive note, it's the first time cisco have been found there since 1985.
"At Corey Lake (also in St. Joseph County), we didn't find any," Hanshue said. "They were last reported there in 1966. So it's possible they've been eliminated in that lake."
The survey has produced some eye-opening results in past years.
"In Hillsdale County, we hit the Sand Lake chain, where the last reported capture was in 1886," Hanshue said. "But a couple of years ago we got a fair number out of that lake. So even with development pressure, these lakes are retaining their water quality."
Murray Lake in Kent County, which is known as a muskie lake, also has a good population, Hanshue said, though the adults tend to be small, 8 to 11 inches. Green Lake in Allegan County has a good population with adults ranging from 11 to 13 inches.