Spread of zebra mussels to Lake of the Woods should be a wake-up call

Several weeks ago, the Department of Natural Resources announced that Lake of the Woods is infested with zebra mussels. This is one of Minnesota's most treasured fishing lakes and, at six times the size of Mille Lacs, our second-largest lake. It can safely be assumed that humans were the cause.

Because there is no technology on the horizon that can control an aquatic invasive species (AIS) in such a large lake, we can assume Lake of the Woods is infested for the indefinite future.

This news is particularly tragic because Lake of the Woods is already infested with invasive spiny water flea. Together, these invasive species can deplete microscopic food, causing dramatic reductions in game fish. Introducing zebra mussels to Lake of the Woods also risks infesting a vast array of interconnected lakes and rivers, including the Boundary Waters, from which still other infestations could spread.

In addition to AIS, a combination of climate change, habitat loss, heavy fishing pressure and pollution are already damaging Minnesota's lakes. Together, they have amplified impact, locking in damage. Well over half our lakes are now either infested with AIS or impaired by pollution. The number has been steadily increasing for years, despite tens of millions of state tax dollars spent looking for technological fixes and refinements to now outdated management plans.

Existing policies to preserve our waters are not working, the science needed to reverse this downward trend is not keeping pace, and this is a crisis.

What can we do? Experience has shown that refuges work. Many forests and their wildlife have been saved by national and state parks, waterfowl by refuges, songbirds by arboretums, bees by pollinator gardens, and coral reefs by marine protected areas. We must create aquatic refuges for our lakes and their fish to shield them from AIS, climate change, development, habitat loss and pollution.

Only a few would be needed, carefully selected using the best science to simultaneously address all five threats across our entire state. In these refuges, aquatic ecosystems would flourish and fish would have the opportunity to grow to sizes not seen in generations, serving as valuable brood stock for the DNR, with many out-migrating to produce new trophy fisheries for anglers.

Nearly 75 years ago, people living on the coasts started setting aside marine protected areas (MPAs) to save marine ecosystems and their fishes. MPAs now cover nearly 5% of the global ocean. One of these is Merritt Island Refuge in Florida, created half a century ago. It now nurtures over 1,500 aquatic and terrestrial species, while attracting tourists and serving as the source of over half of all world record black and red drum caught in Florida. Our fresh water deserves similar treatment.

A system of aquatic refuges could easily be created by re-purposing a few of our public lands and their watersheds. To get started, we simply need to select our most valuable, best preserved, and deeper (so most resistant to climate change) public lakes and/or rivers, and then commit to actively shielding them from development, pollution, AIS introduction and overfishing.

Headwaters would be preferred. Excellent candidates are already found in our state parks, scientific and natural areas, tullibee refuges and aquatic management areas, which already offer some protection as well as infrastructure.

Lake Itasca is an obvious choice. Public access could continue but private boats could not be brought in, and fishing would be catch-and-release. Surrounding lands would be rigorously preserved. In the future this system could be expanded.

But for now, we could rest assured that our most valuable waters and their species would be protected for future generations, while effort continues to develop fixes for our growing list of damaged lakes.

The infestation of Lake of the Woods is tragic. A greater tragedy would be to fail to learn from it.

Peter W. Sorensen is a professor in the Department of Fisheries, Wildlife and Conservation Biology at the University of Minnesota. The views expressed here are solely his own.