New Zealand Mudsnails & Angling During Covid-19

May 7, 2020 | Members, Recreation

There are some big lessons novel coronavirus has taught us over the past two months:

  1. Seemingly disparate things are connected in complex, tangled ways.
  2. Small and simple actions have profound impacts.
  3. We’re a community, and we have to look out for each other (especially our most vulnerable members).

Luckily for all of us who prefer to recreate in and on water, outdoor activity is considered essential under the Safer at Home order.

But unluckily for our streams and rivers, there’s a worrisome link connecting this virus to the health of Wisconsin’s waters. To connect the dots between two disparate things, added recreational pressure—fueled by the mental and physical benefits of spending time in nature—may inadvertently hurt the rivers and streams we all love by leading to the spread of an invasive species.

Case in point: New Zealand mudsnail (NZMS for short). The alarm bells were raised a few years ago when this particular invasive species was first discovered on the outskirts of the Driftless Area near Madison, and there were (and continue to be) plenty of reasons to worry:

  1. These snails are incredibly small (think of a grain of rice).
  2. They reproduce quickly (one snail can have over 200 babies per year) and reach extremely high densities (up to 800,000/square meter).
  3. They have no natural parasites or predators (they pass through trout guts undigested).
  4. They can survive out of water for almost a month, and
  5. (terrifyingly…) it only takes ONE snail to start a new population.

During the past several weeks, there has been a noticeable uptick in the number of visitors to many of Wisconsin’s trout creeks, notably Black Earth Creek (one of the few places in Wisconsin known to contain this troublesome invasive).

Hypothetically, if you fished Black Earth Creek (or one of the six other streams known to harbor these snails) and a NZMS attached itself to the bottom of your boot without you realizing it, you could unknowingly transport a snail (that could potentially start a new population) if you fished in a different mudsnail-less stream the next day (or even three weeks later).

It would be devastating if increased fishing activity in response to COVID-19 gave these snails the chance to spread further into the Driftless.

But, as we’ve learned, small actions matter. Simple precautions that take almost no time are invaluable for keeping New Zealand mudsnail contained:

  1. Take a close look at your boots and waders before and after you go fishing, and brush things off for good measure.
  2. See a wader wash station? Use it. Want one near where you fish but don’t have one? Let River Alliance know.
  3. If you see something, say something. Early detection is the key to preventing the spread of all invasive species. If you think you’ve discovered a new incidence of NZMS, please let the Department of Natural Resources know.

Lastly, we are a community. As we each do what we can to keep the more vulnerable members of our society safe during this unprecedented time, let’s do the same for our voiceless and vulnerable rivers and streams that rely on us to protect them.