Imported (exotic species)
By Joe Feimer and Tony Deluxe
Why do people import non-native species?
People often import species to have as pets (ex. Burmese pythons) or to control other species (ex. Cane Toad - control the cane grub). Sometimes, they are brought to other areas by accident (ex. Zebra Mussels - came in the ballast of ships).
What is the impact of imported species on the native ecosystem and why does this occur?
- preying on native species
- out-competing native species for resources
- bringing disease
- preventing native species from reproducing
Indirect effects of imported species are:
- modifying food webs - they can deplete native food sources
- decreasing the biodiversity of an ecosystem - replace some species
- altering the conditions of an ecosystem - they can change soil chemistry
Examples of non-native species in the U.S.:
the Emerald Ash Borer,
the European Starling,
and the Northern Snakehead.
What has been/can be done to prevent the importation of non-native species? What has been/can be done to fix the problem of species that have already become invasive?
The U.S. Fish and Wildlife Service works on imported species. For a person to legally import wildlife, they need to have a license, to pay fees, use designated ports, and abide by the laws set to regulate this type of importation.
The National Wildlife Foundation is working to stop the problem of imported species. They rely on detecting the invasive species early, then eliminating them quickly. They also want to prevent the importation of non-native species.