By Penny Bernhard-Schaber
Summer has come, and with it has come more opportunities to enjoy Wisconsin’s natural heritage, whether you’re fishing, swimming, boating, hiking, or camping. But summer also a good time to reflect on all the hard work that goes into protecting our natural resources so our children and grandchildren have a chance to enjoy them as well. That’s why June, July, and August have been named “Invasive Species Awareness Month,” “Lakes Appreciation Month,” and “National Water Quality Month” respectively.
When non-native plants and animals are brought into the state, they throw our ecosystems out of balance. Without any checks and balances from natural predators and competitors, these new species can reproduce uncontrollably and crowd out native species, which can be a significant threat to the parks, forests, and waters we use for recreation. For example, invasive species like round gobies and rusty crayfish eat the eggs of sport fish such as small-mouth bass, trout and sturgeon in the near-shore areas of Lake Michigan. This threatens a sport and commercial fishing industry that supports 81,000 jobs in the Great Lakes region.
Invasive plants can be a problem too: wild parsnip, which grows along roads and hiking trails, produces sap that makes skin extra sensitive to sunlight, and can cause severe burns just by brushing against it. I experienced this firsthand while hiking the Ice Age Trail, and it is not an experience I’m eager to repeat. Hunters, hikers and birdwatchers can also find that they are no longer able to walk in their favorite natural areas.
Garlic mustard, dense stands of buckthorn and other invaders fill in the understory of once open native forests and grasslands. As the habitat is modified by such invasive plant species, the wildlife that depends on it disappears as well.
Invasive animals such as the mute swan can also change our wildlife opportunities by chasing away all other waterfowl from the bodies of water they occupy. The Wisconsin DNR (dnr.wi.gov/topic/Invasives) and the UW Extension (uwex.edu/erc/invasives.html) have more information online, including which species to look out for.
Invasive species aren’t the only thing we need to keep out of our lakes and rivers. Storm water runoff also has the potential to ruin your vacation by promoting the growth of blue-green algae. When the water is warm and enriched with nutrients like phosphorus or nitrogen, blue-green algae bloom and can cover lakes, ponds, and slow-moving streams with a layer of scum.
When these algae get out of control, they can devastate a lake’s ecosystem. Blue-green algae blooms block sunlight from the plants that the lake’s fish rely on for food. They also take oxygen out of the water, creating dead zones where fish can’t breathe. If that weren’t enough, blue-green algae also secrete a toxin that can make you sick. It can be absorbed through the skin while swimming, inhaled while boating and it can even contaminate fish caught from the lake. When blue-green algae are in bloom in a body of water, it’s not safe for any form of recreation.
We all have a part to play in keeping our outdoor recreational areas safe from invasive species and blue-green algae. A few extra steps can help prevent the spread of invasive species: check your boat or other watercraft for plants and animals before moving it to another body of water, check your clothes and pets’ fur for seeds before heading home from camping or hiking, be sure not to leave bait behind, and be sure not to move firewood from one part of the state to another.
You can help reduce blue-green algae blooms in the future by reducing the amount of fertilizer used on your lawn, fixing leaking septic systems, and only using phosphorus-free detergents and fertilizers. Our natural resources belong to all of us, so we all have the responsibility to make sure future generations have the same options for summer fun that we do.
Help Proected Our Woods and Waters
By Penny Bernhard-Schaber