Midwest Region


Bad Actors: 11 Animals We Hope You Never Meet in Midwest Waters

October 29, 2015

Wels catfish courtesy of Andrea Janitzki/Creative Commons.
Wels catfish courtesy of Andrea Janitzki/Creative Commons.

In an era when the Midwest is frustrated by a seemingly endless litany of unwelcome guests in our waters, from zebra mussels and Asian carp to Eurasian watermilfoil and spiny water fleas, we have decided that enough is enough.

It’s time to go on the offensive.

The U.S. Fish and Wildlife Service’s Midwest Region is helping to stop the next invasion of nasty critters in our waterways before it even begins. We’ve scoured the globe and created a bad actor list of 10 fish and one crayfish that we want to make sure never find their way to the Midwest. Nearly all of these animals would find our rivers, lakes and streams a suitable home. Coupled with their unfortunate tendency to invade new places, we’ve decided the risk these animals pose to our environment is too high.

Why Prevention is Key

Experience has taught us that invasive species remedies are costly, both in time and in resources.  Additionally, society loses billions of dollars a year because of the damage invasive species cause to industries and the environment. Stopping invasive species before they cross our borders is the most efficient and cost-effective approach to battling these unwelcome guests.

In the absence of a magic crystal ball to show us future invasive species, we turn to science to help us create a line-up of our bad actors. We use a process we call Ecological Risk Screening Summaries to focus our prevention efforts. Starting our bad actor search with freshwater animals, we use international databases, scientific literature, and a computer model to locate areas of the United States that provide the right climate, such as temperature and rainfall patterns, for animals known to be invasive in other parts of the world. The potential risk an animal poses to our country’s waters increases when we find a strong climate match.

Preempting the Next Invasion

Ecological Risk Screenings have revealed our bad actors.

Amur sleeper. Crucian carp. Eurasian minnow. European perch. Nile perch. Prussian carp. Roach. Stone moroko. Wels catfish. Zander. Yabby crayfish.

The next step is to keep them out.

The Service’s Fish and Aquatic Conservation Program used the information collected in the Ecological Risk Screening Summaries to support a multi-species proposed rule that evaluates the 11 species for potential listing as injurious under the Lacey Act. If the rule is finalized into a regulation for some or all of the 11 species, it will make the import of any of these animals illegal, except with a permit for certain purposes. It will also demonstrate our narrowing focus in our battle against animal invaders. While the Service has listed at least 200 hundred species as injurious before they entered the United States in many separate listing actions, we have never focused so completely on preventing the introduction of all species that are in a single listing action.

Another crucial part of the effort to stop animals before they enter our country is our partnership with industry and state conservation agencies. In 2013, the Service signed a Memorandum of Understanding with the Pet Industry Joint Advisory Council and the Association of Fish and Wildlife Agencies. Both groups agreed to help us in our efforts by voluntarily refraining from the importation of high risk species not yet introduced to the country in trade. Their ongoing support is a vital part of our future success.

The interplay of science, policy and partnerships is important in our fight to keep invasive animals out of Midwest waters.  The Service is currently taking steps to place Amur sleeper, crucian carp, Eurasian minnow, European perch, Nile perch, Prussian carp, roach, stone moroko, wels catfish, zander and yabby crayfish on the injurious species list. If successful, our hope is that the names on our bad actor list slip from your memory in a few months or years. It will mean our offensive is doing the job. With help from our partners we preempted the next invasion before it ever became a problem.

Interested in learning more about our 11 bad actors? Read their Ecological Risk Screening Summaries or learn more about commenting on the proposed rule.


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Last updated: June 15, 2016