25 years ago Muskie weren't in Fox River. Steve Hogler, fisheries biologist with the Department of Natural Resources, set a fyke net and in less than 24 hours, 18 adult muskies traveling upstream had been funneled into the underwater trap.
The muskies ranged from 34 to 54 inches in length. The muskies were moved in several shifts to a processing area at a nearby public boat launch. There the fish were measured, weighed, inspected and tagged. Eggs and milt also were taken from several fish.
It's all part of the state's management program for the Great Lakes spotted musky. Though native to Green Bay and other Lake Michigan waters, the species was effectively eliminated through the mid-1900s by a variety of factors, including habitat degradation and water pollution.
In the 1980s, the DNR launched a reintroduction program for the native strain. The first fish were obtained from Michigan and stocked in 1989. Stocking levels rose from about 4,000 fish per year in the early 1990s to about 30,000 fish per year in the early 2000s.
The fish grow quickly in the forage rich waters of Green Bay. A female musky reaches 40 inches in just five years, according to DNR figures, and many fish over 50 inches are caught each year.
The discovery of the fish disease viral hemorrhagic septicemia in Lake Michigan halted the project from 2007-'09, when stocking was suspended. Stocking has resumed with about 3,000 muskies over the last two years; the fish are raised in an isolated pond near Kewaunee.
The first step in the process occurs on the banks of the Fox. A 48-inch, 30-pound musky is laid in a water-filled cradle as it is quickly measured, weighed and sexed. A hypodermic needle injects a passive integrated transponder (or PIT) into the fish's muscle. The device is the size of a grain of rice; if the fish is handled again, it will assist with population studies. A piece of fin is clipped for a genetic study, and a small sample of blood is drawn. Then the female's belly is massaged, yielding a stream of tiny, amber eggs. The eggs are collected in a stainless steel bowl and combined with milt from males handled earlier. The fertilized eggs will soon take up residence at the DNR's Kewaunee facility. By fall, the 8- to 15-inch fingerlings will be stocked at sites around Green Bay.
One of the goals of the musky project is to re-establish a naturally reproducing population in and around the bay. So far, only a handful of wild muskies have been documented, most recently one each in Sturgeon Bay and the lower Menominee River.