Fish and chips

Tiny sensor helps track muskies’ growth in Pierce Lake


LOVES PARK — Kevin Bunch spends about 10 hours a week fishing for the prize of Pierce Lake — the elusive muskie.


“Pierce is close,” the Loves Park fisherman said. “I can go out there after work and fish for two or three hours, then come home in time to eat supper.”


Last year he caught a dozen muskies on the Rock Cut State Park lake. His biggest was 41 inches.


The muskie is considered one of the toughest species to catch, often called “the fish of 10,000 casts,” and most muskie anglers bypass Pierce for northern Wisconsin’s trophy lakes.


However, a tiny computer chip used in a 10-year study might some day greatly improve muskie fishing at Pierce, right in our back yard.

Pierce is one of three Illinois lakes in the Project Green Gene study, which began in 2002.


Small muskies from three different genetic strains are stocked each year in Pierce, Lake Mingo in central Illinois and Sam Dale Lake in southern Illinois.


The muskie strains are from the Ohio River drainage; Upper Mississippi River drainage, which includes Minnesota’s Leech Lake and Wisconsin’s Lake Minocqua; and a mixed strain from the Illinois hatchery.


“The main goal of the project is to look at how different strains of muskie perform as far as growth and survival in Illinois waters,” said Curt Wagner, the project’s data manager with the Illinois Natural History Survey.


“The main thrust is we don’t have natural reproduction of muskies here. Obviously if you had natural reproduction you would want to go with the native fish.”


The state Department of Natural Resources has been stocking muskies for decades, but hopes the study will lead to a hardier population.


The three lakes are stocked annually with 250 muskies from each strain in the 10-inch range. The stocking will continue through the first five years of the study.


The DNR periodically uses trap nets to recapture some of the muskies after the fish have had some time to grow. That’s when the computer sensor is inserted under the skin.


The tag, which cost about $5 each, works like a bar code at grocery stores, providing a personal identity for the fish and recording its strain. The system is similar to those used by veterinarians to identify pets.


An electronic wand is passed over the netted fish to see if the muskie had been tagged previously.


“Once they have been in the lake at least a year and we recapture them in our boat, we inject them with the tag because that fish has a higher probability of making it,” Wagner said. “As we go, more and more of our fish in the lake will have the sensors in them.”


When one of the tagged fish is captured, it is weighed and measured so its growth can be tracked.


The study’s results will be examined after 10 years to determine the best muskie strain for Illinois lakes. Wagner has seen a trend among the early results.


“We are seeing that the Ohio River drainage fish seem to grow better and survive better,” he said.


DNR staff captured 18 muskies in six trap nets last week at Pierce Lake. The biggest was 42 inches and 20 pounds.


However, only one muskie among those caught had a sensor. It was 36 inches and 15.13 pounds and had been stocked in 2003.


Dan Sallee, DNR regional fishery administrator, said Pierce’s muskie numbers show promise.


“I do think we are building a muskie population at Pierce. There’s no doubt about it,” he said.


A general formula for a successful population at a lake is a minimum of one-half a fish per net for each night. Last week’s sampling at Pierce provided 18 muskies in six nets over night, an average of three fish per net.


“So we have six times as many muskies as are needed for the minimum of a successful stocking program,” Sallee said.


“But there’s lots of trade-offs. Higher densities can sometimes mean lower growth rates.”


Steve Ruhmann, president of the local Flatlanders chapter of Muskies Inc., also sees a bright future for Pierce.


“It has the potential to be a good muskie lake,” he said. “Right now on a 1-to-10 scale, it’s a 4 or 5, but it’s getting better.”


The fishing club has stocked muskies at Pierce in the past, and has worked to improve the structure on the lake’s floor.


“Our goal is to be able to go over there and have a chance to catch a legal (48-inch) muskie,” Ruhmann said.


A trophy in our back yard.


Staff writer Doug Goodman can be reached at 815-987-1386 or dgoodman@rrstar.com.