An invasive species is any plant, insect, fungi, bacteria or animal that is not native to a specific ecosystem. It can even include an organism’s seeds or eggs that doesn’t naturally occur in a specific area. Invasive species are usually spread by humans, often unintentionally. Since humans have the ability to travel to and from different places, we often bring along hitchhikers. Invasive species can stowaway in or on boat, wood, plants, and even our clothing and vehicles. Some invasive species are accidentally or intentionally released which is most commonly seen in the pet trade. Pets sometimes get lost, or some people realize that they can no longer care for that particular pet, and release it into the wild, disregarding the potential conflicts. Invasive species can wreak havoc on an ecosystem as they can out-compete native species for food and other resources.

Some species can be invasive in one area, but native in another. In parts of Montana, the brown trout is the invasive species and are out competing native cutthroat trout. I worked with a fish crew from the USGS to study the effects of this problem. We installed under water antennae that will scan and read trout that have been pit-tagged. Each pit-tag has a unique I.D. number which will be associated with a particular fish. Some of the data collected will include the time of day that fish swam over the antennae, and what direction they were traveling, whether it was upstream or downstream. This data is useful because it can show us how native species are being affected by the invasive species. The overall goal is to be able to come up with sound ecological solutions to help alleviate the problem.