Invasive species wreak havoc on our environment—but there are ways you can help prevent it.

An invasive animal or plant is a non-native species—that is, one from a different locale—that once introduced, can harm its new environment. That can come in the form of environmental distress, economic damage or a threat to human health.

In the native environment, each species’ growth is checked by another’s, so no one group dominates. But in a new and different locale where that balance doesn’t exist, invasive species’ populations can take off. And that can be disastrous for native plants and animals.

You can help stop the spread by cleaning boats, hiking boots and other outdoor gear between uses. And never turn unwanted animals out into the woods or dump aquarium tanks or fish into the wild.

Take the pledge to stop the spread.