Lansing — The Michigan DNR is soliciting feedback from anglers on proposed changes to walleye and yellow perch regulations on Saginaw Bay to better balance predator and prey fish populations.
Current regulations allow for a 15-inch minimum size limit and a five-fish daily bag limit for walleyes in Saginaw Bay’s Lake Huron Management Unit (MH-4), including the mouth of the Saginaw River to Center Point Bridge. DNR officials are proposing two options to reduce the bay’s walleye population, which officials believe is preventing young perch from reaching maturity.
The DNR wants to change the minimum size limit to 13 inches, with either an eight- or 10-walleye daily bag limit, though not all local anglers think reducing the minimum size is a good idea.
“Some of our members are not in favor of a 13-inch walleye, because there’s not enough meat on a 13-inch walleye,” Laura Shorkey, president of the Saginaw Bay Walleye Club, told Michigan Outdoor News.
“They are not in favor of the 13-inch limit at all, and if they have to go to 13 inches, they want an eight-fish bag limit, not 10,” Shorkey said. “And they don’t want the river to remain open to Center Street Bridge.”
Shorkey said about roughly half the members of the club oppose a 13-inch minimum size limit, while the majority want the river mouth closed during the winter.
“There’s no way to make sure people don’t go out multiple times” a day during the winter to take vulnerable walleyes at the river mouth, “which happens now,” Shorkey said.
DNR Southern Lake Huron Management Unit manager Jim Baker said the growing walleye population in Saginaw Bay is “getting to the point it’s affecting walleye growth” because of a limited prey base, and the fish are eating more young-of-the-year yellow perch.
“These options were settled upon by all the biologists that are part of the Lake Huron Basin team,” Baker said. “We kicked around a whole lot of different options and these are the ones we thought could best deal with the situation of a growing walleye population and declining forage base.”
Dave Fielder, DNR fisheries research biologist, said the problem with walleyes is “not just slow growth, but also an abundance of small fish.”
“The fish growth rate is a function of its density,” Fielder said. “The more of them there are, the slower they grow.”
The walleye-recovery goal for Saginaw Bay is based in part on growth rates, which equated to about 130 percent of the statewide average after the alewife population crashed in Lake Huron in 2003. DNR officials considered walleye recovered in the bay once that growth rate met the state average, which occurred in 2009, Fielder said.
“Now the growth rate has come down some,” he said. “They’re right around the state average.”
Based on the DNR’s computer model estimates, Saginaw Bay’s adult walleye population of age-2 or older fish peaked at 3.96 million fish in 2007, with the last available estimate in 2011 of roughly 2.5 million walleyes.
“The balance with the available prey is what’s concerning us,” Fielder said.
Recent surveys in the bay revealed walleyes are consuming a lot of young yellow perch, which is impacting the species’ ability to reproduce. The proposed walleye regulation changes are designed to help boost perch numbers, but DNR officials also are proposing to cut the daily bag limit of yellow perch from 50 per day to 25.
“The reduced possession limit will conserve the remaining adult perch and may help juvenile perch in Saginaw Bay,” Todd Grishke, DNR Lake Huron Basin coordinator, said in a statement. “This tactic – as well as commercial fish reductions and other strategies – will hopefully restore yellow perch to greater abundance.”
Other efforts to curb perch predation include a DNR request to cull more cormorants, as well as efforts to re-establish ciscoes in the bay. Ciscoes are members of the whitefish family native to Michigan that provide both another forage fish when they’re young, and sportfishing opportunities when they’re full-grown, officials said.