Investments to increase DNR's fish rearing capacity

DNR employee feeding fish at Thompson State Fish HatcheryBig changes are coming to the Department of Natural Resources' Little Manistee River Weir and Thompson State Fish Hatchery thanks to the renovation support provided by the Michigan Legislature and Governor Snyder in the fiscal year 2017-18 budget. The total investment is estimated at more than $12 million.

The changes at the Little Manistee River Weir, located in Manistee County near Brethren, are intended to shore up the facility and secure steelhead and Chinook salmon egg collection efforts well into the future. Since 1968, the Little Manistee River Weir has served as Michigan's sole egg source for steelhead. It also serves as the primary source for Chinook salmon eggs. It has seen a few updates over its nearly 50 years of service, but they have all been relatively minor.

"We've been pursuing upgrades to this facility for years now, so we were really happy to hear the project is a go," said Central Lake Michigan Management Unit Manager Scott Heintzelman.

The proposed upgrades will modernize the facility significantly. Upgrades include replacing the badly aging generator that provides backup power during outages; old, inefficient pump motors; the ancient fish crowders with modern technology; as well as completely reworking the fish holding ponds. Given the salmon program is so much smaller now due to ecological changes in the Great Lakes, half of the ponds are likely to be taken out of service altogether. Outdoor lighting upgrades and installation of a more reliable alarm and monitoring system are also being considered as part of this project.

The improvements are not limited to just the weir. Most of the capital outlay funds will actually be spent at Thompson State Fish Hatchery, located just west of the U.P. town of Manistique. A portion of those funds will go toward increasing production of smolting sized steelhead. Upgrades in that area include adding another deep (2,000 feet) well, replacing the more than 40-year-old feeders, resurfacing the indoor and outdoor rearing tanks, and adding a UV filter to keep fish diseases in check. The deep well will provide additional water that picks up enough geothermal heat to make it the right temperature (around 52oF) to allow the fish to reach smolting size by spring. This will increase production by an additional 200,000 large steelhead smolts each year, an increase of 15-20% over existing state production.

"Anglers have been consistently asking for more steelhead, so this is a big win for us and for them," said Fisheries Division Chief Jim Dexter. "These fish need to get to the correct size for stocking, and Thompson State Fish Hatchery is the only place we could do this."

The most visible changes at Thompson will be the addition of a coolwater production facility. Fishing for coolwater species (walleye, muskellunge and northern pike) has been steadily gaining in popularity for years now. That means the demand for hatchery produced coolwater fish has been going up as well. In fact, demand far outpaces the DNR's ability to supply fish, given the current system. The DNR fish production system has maxed out its coolwater production capacity and has essentially been using retrofitted coldwater hatcheries for coolwater production.

Walleye production is almost entirely limited to a number of ponds scattered across the state that are operated by DNR fisheries technicians. Many of them have been operated with the help of various angling groups and have been very successful, while others are much less reliable.

Muskie production in the current system is limited to just four small lined ponds located at Wolf Lake State Fish Hatchery near Mattawan. Muskies reared in those ponds start out in a group of tanks that were fit into the basement of an on-site building. Rearing restrictions do not allow for a northern pike rearing program to be active at the same time muskies are being reared.

"The Wolf Lake crew has done an amazing job of stabilizing the muskie program in this system, but production from the four ponds is limited to 25-30,000 fall fingerlings annually," said Fish Production Program Manager Ed Eisch. "The new coolwater facility planned for Thompson Hatchery will change that significantly."

The plans call for infrastructure enhancements and developments which will allow the DNR to increase production by up to 15,000 muskies and up to 250,000 spring fingerling walleye.

"While completion of this project won't get production capacity fully in line with demand, it's clearly a big step in the right direction," said Dexter.

DNR staff has already begun the process of selecting a design and engineering firm. Design work will take up to a year, with another 12 to 18 months for construction.

"With a little luck, we may be ready to start rearing fish in the new coolwater facility as soon as the spring or early summer of 2019," said Eisch. "The weir project will be bid out separately for construction so that project may be done a bit sooner, maybe even in time for the spring 2019 steelhead run."