LADYSMITH – The day was warm, the water temperatures hovering between 89 and 90 degrees, making it more comfortable for students from three Rusk County high schools who spent the morning up to their necks in water.

Some students in a boat mixed cement to anchor individual spruce trees to the bottom of the Dairyland Flowage while others swam or waded with trees they positioned at the sides of submerged rock piles. The rocks had been dropped through the ice along the shore during the winter.

The position of the rocks had been marked with a GPS. Those coordinates, plus some searching by students, helped locate the piles this summer. The individual trees with cement foundations would be placed between the rock piles to provide additional cover.

The idea is to provide a diversity of habitat to give minnows and small fish a place to live, which in turn will provide food for bigger fish, said Jerry Carow of the Rusk County Wildlife Restoration Association, the nonprofit group coordinating the project.

The work began three years ago when Dairyland Power Cooperative drew down the reservoir to repair a dam. The association and Dairyland Power took the opportunity to haul rocks and trees onto the dry lake bed to create aquatic habitat.

When the power company refilled the lake, they saw no reason to stop creating habitat. They just had to change their methods, Carow said. Because Dairyland Power has a five-year permit from the state Department of Natural Resources to create habitat in the lake, they decided to keep going with that work.

Since the project began three years ago, the power company has brought in about 6,400 cubic yards of rock – the equivalent of a four-mile stretch of rock three feet wide and three feet high, Carow said.

So far the project has involved the installation of about 2,000 trees. Another 500 to 1,000 could be added, Carow said.

The project involves students from Flambeau, Bruce and Ladysmith high schools during summer months. During the rest of the year, prisoners from Flambeau Correctional Center provide the labor.

Fat fish

The habitat work appears to be helping fish in the flowage, said John Thiel, senior environmental biologist with Dairyland Power.

Natural reproduction of walleyes always has been good on the flowage, an impoundment of the Flambeau River, but growth of the fish typically has been slow, he said. Now the walleyes are growing faster.

“We’ve had a 2-inch increase in the average size of walleyes we’ve collected,” Thiel said.

During the next few years, more walleyes should be moving into the legal size range, he said.

Black crappies have become more abundant and also are growing well, Thiel said. Bluegills are not abundant in the flowage but are more common now than they were, as are perch and smallmouth bass.

When the reservoir was created in the early 1950s, the power company removed trees logs and stumps along the shoreline. Officials at the time figured drifting wood might interfere with power generation.

“At the time they didn’t realize they were removing all the good fish habitat,” Thiel said. “What the lake really needs is shallow water fish habitat.”

The reservoir always has been home to big muskies, but the waterway is low on suckers, a favorite food of muskies. One potential problem was a perched road culvert on nearby Crooked Creek that may have been blocking upstream spawning movements of suckers and other fish in the spring. Officials lowered the culvert so fish could get upstream, and they plan to survey the creek later this summer to find evidence of spawning by suckers, Thiel said.

Regulations

Dairyland Power and the wildlife association had wanted to bring in heavy equipment and move some existing gravel on the reservoir’s bottom three years ago when the reservoir was drained, but the DNR nixed that idea because of mercury contamination in the sediment. The mercury came from paper plants upstream.

Thiel thought the project could have been completed without recirculating mercury in the system – Dairyland had done some testing of the sediments – but the power company lost that argument.

That decision caused Dairyland Power to change plans and downsize the reefs they wanted to build, but, with the help of the wildlife association and other community groups, fish habitat in the flowage is much improved, he said.

Summer jobs

This is the fourth summer that Charlie Coughenour, a student at Ladysmith High School, has done conservation work for the Rusk County Wildlife Restoration Association.

“It’s a lot of fun. It gives me something to do in the summer, plus I get paid,” said Coughenour, who will be a senior this fall.

Twenty-four high school students worked this summer on the project, which included fish habitat improvement, repairing erosion sites, building a nature trail and creating fishing access sites.

Students work for five weeks and earn $24 per day, plus one-half of a high school credit. The students are supervised by teachers and four college interns.

Coughenour said he has learned some construction skills in the program and it’s also influenced his career choice. He plans to attend UW-Stevens Point and study environmental science.

Knight can be reached at 715-830-5835, 800-236-7077 or joe.knight@ecpc.com.

Published: Saturday, July 02, 2011

The Wisconsin Department of Natural Resources is constantly doing research on the rivers and lakes in the state.

When you consider the thousands of lakes and thousands of miles of shoreline on the state’s rivers, the DNR has a never-ending job in keeping our waters clean — free of pollutants, protecting our resources and providing good fishing opportunities to the million and a half anglers who purchase resident and non-resident licenses.

Every spring, I go on to area lakes with DNR technicians as they electro-fish and fyke net fish on the Madison Chain of Lakes. The Madison lakes are regularly netted and shocked every five years for information and data on each lakes fishery and what is planned for the future in stocking and fish species.

For example, some of the research is the stocking of the Leech Lake muskie strain and the Wisconsin or Thompson muskie strain in local lakes to see which muskie does better in our waters and what muskie strain stocking is better economically. Much of the research being done will not produce results for years with the relatively slow growth of the muskie.

Recently, I happened to be up near the Prairie du Sac Dam on the Wisconsin River doing some wading for smallmouth bass. Near the VFW boating landing, I ran into Dr. Brian Weigel, a DNR fisheries researcher from the DNR Science Services Department, and Kurt Welke, DNR fish biologist and manager.

They were on the Wisconsin River researching the temperature preference of walleyes because the river’s temperature is now near the thermal preference threshold for walleyes. Many scientists and researchers predict that climate change will bring warmer water to the Upper Midwest, which may impact what fish species will inhabit and survive.

Conditions for fish — and walleyes in particular along with their close cousin the sauger — could be difficult in the future with an increase in the river’s water temperature which is predicted to be above the fish’s comfort zone. The researchers want to know where the walleyes are going in the warmer water of summer.

The day I ran into the DNR, they had two boats with fisheries technicians and grad students electro-fishing the waters below the dam for walleyes.

The electro-fished walleyes were put into a tank and revived from the shocking. Then, Weigel and Welke would cut a slit with a scalpel along the walleye’s stomach and insert a transmitter into the abdominal cavity.

The transmitters are about the size of an AAA battery. The cut was then stitched with monofilament line and patted down with iodine to prevent infection. The walleyes were then put into a “holding tank” which had a water re-circulator to keep the fish alive and give them time to recover before being released back into the Wisconsin River.

Weigel and Welke wanted to get 25 to 30 fish near the dam for their study. They seemed to be reaching their walleye quota.

The radio transmitters that are put into the fish will show where they are “hanging out” during the warmer months of the year. Walleyes have to be at least 16 inches long and preferably longer for the transmitters — which along with the software will allow Weigel to record data for two years. The transmitters are turned off during the winter.

There may be things done in the future to enhance the walleye’s survival such as improving fish habitat and changing the river’s water flow. The Wisconsin River fishery is a valuable and very vulnerable resource which deserves all the protection and help that it needs to provide fishing and recreational activities to all.

The trees and soil along the river’s banks are falling into the river at an alarming rate. The river seems to change every year with deeper areas getting filled in with sand and silt. Once one gets past the Highway 12 Bridge at Sauk City, it is difficult to find water deeper than 10 feet. The only really deep water is directly below the dam in the “scour” hole created from high water in the spring.

Weigel and his crew also electro-fished the Lower Wisconsin River from the Highway Y boat landing to Arena and only “caught” eight fish. There seemed to be many more walleyes in the immediate area below the Prairie Dam the previous day. This may be because the fish hadn’t migrated downriver yet, the larger females were still recovering from spawning, the fish were staying near the dam because of the deep water, or the fish were gorging on forage fish.

The DNR is trying to answer these and many more questions if we are going to continue to have a walleye fishery on the Wisconsin River. But, the real question is, where do walleyes go in warmer water?

Maybe they’ll go to the Mississippi River or do they cease to exist in the warmer river?

Only time will tell, but at least the DNR is pursuing the questions.

Contact Gary Engberg, a freelance outdoors writer, at gengberg@chorus.net, call 608-795-4208 or visit his website at http://www.garyengbergoutdoors.com.