Lake Ellwood Update: Without Chemicals, Fish Return

Eurasian Watermilfoil (c)Eric Engbretson

Last year on this blog, I wrote a piece about Lake Ellwood, the Florence County lake where reproduction by bass and bluegills had come to a halt due to lack of aquatic plants in the lake.  (You can read my original posting here.)  In the meantime, there's been some interesting new developments that I'd like to share with you in the following Lake Ellwood Update:

In the spring of 2013, an application from the Lake Ellwood Association to further chemically treat about three acres of Eurasian Watermilfoil was denied by the Wisconsin DNR.  Instead, a 5 year whole-lake study began on the lake in the summer of 2013 headed by Dr. Greg Sass of the WDNR's Fisheries and Aquatic Sciences Research Section. The goal of the study is to better understand why a drastic change in the fish community occurred between 2002-2012 and to test for effects of chemical treatments/reduction in aquatic plants on the Lake Ellwood fishery.

In the early stages of the study, noticeable changes have already been observed.  Since chemical treatments have ceased, the fish and aquatic plant community has responded.  The most recent fish surveys conducted during September and October of 2013 revealed robust year classes of bluegills and largemouth bass.  Native aquatic plants have also rebounded.  Littoral areas that were barren just one year ago now have lush colonies of native plants.  "I couldn't believe how fast the native plants returned", remarked an amazed Greg Matzke, Florence County Fisheries Biologist.

Matzke is optimistic about the five year study (which doesn't include any further chemical treatments for Eurasian Watermilfoil.) "It's my hope that after taking a very thorough look at the fish community, we can better understand what drives natural reproduction of fish in Lake Ellwood, and provide a plausible explanation of why the fish community crashed and how the fight to control Eurasian Watermilfoil has contributed to it." 

Lake Ellwood still has a few acres of invasive milfoil and likely always will. What's returned are the native plants and young largemouth bass and bluegills.  It's a trade off that feels like an immediate victory for fisheries managers at this point.