Fish Habitat Committee

The LLAA Board appointed a Fish Habitat Committee fall of 2018 to study options for creating additional habitat to promote the Lake Lucerne fishery.  The Lake Association received a $10,000 grant from the Forest County Potawatomi through the Town of Lincoln for the purpose of improving fish habitat.  

Members appointed include Mary Heilmann, Ed Mullaney, Jim Wienser, Tim Sprink, Dave Shlitz, Jack Kloss, Tim Turiff, Verne Kamenick, Jeff Turiff, and Jim Zach as chair.

We met on Feb 21, 2019, and participants included 3 local fish biologists with knowledge of Lake Lucerne: Greg Matzke (DNR), Mike Preul (Mole Lake Sokaogon), and Ben Koski (Forest County Potawatomi).

A very interesting and detailed discussion of Lake Lucerne’s past and present status regarding the fishery occurred, and there have been additional discussions with the biologists and a Rhinelander DNR Water Resource Management Biologist who wasn’t able to be at the meeting, Scott Van Egeren. Rick Hermus has also had additional discussions with Mike Preul. 

Lake Lucerne has some significant fishery ecosystem challenges.

The long term management goal of a self-sustaining walleye population has not been achieved over several decades of stocking walleye.  The main obstacles seem to include lack of forage fish and the possible persistence of a rainbow smelt population in the deeper waters of the lake.  The recent cisco stocking is an effort build up a forage fish population, but the success of that also remains to be determined.  This is the primary current DNR management plan.  In addition, there have been lake trout and whitefish stocking efforts.   Brown trout stocking, last done in 2003, has been discontinued due to cost.  

There seems to be adequate habitat for walleye to spawn on the shores of Lucerne.  However, that hasn’t resulted in significant natural reproduction. Suspected factors include a lack of forage and possibly due to the presence of smelt which will eat walleye fry when the fry migrate from spawning grounds to deeper waters. 

There is an abundance of smallmouth bass in Lucerne which are also contending with a lack of adequate forage. This is resulting in stunting of their growth potential and depletion of crayfish forage.  Bass are not the cause of the fishery problems leading to an abundance of bass, but by their numbers in Lucerne, they do create ecosystem problems.   As Greg Matzke says, “All fish eat all fish.”  As a response to try reducing the bass population, the DNR in 2018 eliminated the size limits on harvesting bass.   An advantage for persons to consume smaller and younger bass is a lesser mercury/PCB load which is a persisting contaminant in WI fish that accumulates as fish age.  Another approach the LLAA will be discussing is whether there are there ways to encourage catching more bass without attracting tournaments which will increase our risk of bringing more invasive species into Lucerne.

In the late 1980s/early 1990s, LLAA members constructed 128 fish cribs on the ice which dropped into 15-20 feet of water.  Many were stuffed with brush which has since deteriorated.  While it was a well-intentioned project with DNR approval at the time, it has since been realized that those structures in deeper water tended to function more as fish concentrators and angler attractors, rather than promoting fish reproduction.  It is now understood that coarse woody debris from falling trees in the shallow shoreline environment (littoral zone) is where much of non-walleye fish reproduction, forage, and early growth occurs. While walleye can benefit from feeding upon some of those fish, their life cycle involves more rocky/gravel shoreline and deeper waters.  However, some of those fish promoted by littoral zone woody debris can also compete with young walleye when in walleye habitat areas.

Two other options have come out of subsequent discussions:
1) Scott Van Egeren has offered to work with LLAA to have the DNR fully fund a habitat survey of the entire lake. This would be a complete survey of the lake’s current habitat — rocky/gravel areas, woody debris, and vegetation; so that we have a more science-based perspective to make decisions regarding habitat in the future.  This information could also become part of a revised comprehensive lake management plan.  Our last one was done in 2005, and those of us who have been around awhile, have seen how our lake is changing since then.

2) The DNR is also offering to assist in possibly making use of our FCP grant by doing a few tree drops or fish sticks in the shallower south end where there is warmer summer water and isn’t deeper water walleye habitat.  The presence of coarse woody vegetation has been demonstrated to improve populations of invertebrates, which provides food and shelter for smaller fish, which provides forage for bigger fish including perch, bluegills, large/smallmouth bass, and northern.  In a less developed shoreline than Lucerne, aging of trees and storms would be contributing more woody vegetation into the shallow littoral zone than is occurring now, and hasn’t for 50-100 years.  Another alternative could be to wait on that until after the complete habitat survey is finished.

It would be useful to know what the predator fish of Lake Lucerne are eating.  It could provide evidence if smelt are still present in Lucerne.  To that end, I’m asking fisherpeople to take cellphone photos of stomach contents of harvested walleye, bass, and northerns and send them to: jimzach50@gmail.com   I will forward them to Greg Matzke.

Submitted by Jim Zach MD, 3/27/2019
Chair, LLAA Fish Habitat Committee 
LLAA Board Member