Exotic Animal Introductions

Introduction of exotic, non-native aquatic animals and plants into the US can, in some cases, cause significant ecological change. Past state and federal actions purposefully introduced exotic plants and animals into the US. Unfortunately, the positive or negative impacts of introductions are difficult to predict. Now, in spite of increased awareness, and a change in introduction philosophies, globalization of trade has increased the challenge of maintaining the biological integrity of the US and its waters.

Unintentional introductions of zebra mussel, green crab, and the Russian round goby occurred through release of ballast water from transcontinental ocean going ships. These aquatic animals are spreading throughout various regions of the US and in some cases, have caused significant harm.

Some imported animals have proven beneficial. For example, the brown trout was imported from Europe and has been widely accepted by the sport fishing community in the US. Similarly, the rainbow trout, native to the Pacific Northwest, has been widely distributed in the US and internationally. It is highly valued by both the sport fishing and aquaculture communities and as far as we know, has had little negative ecological impact.

Various biological controls for weeds or insects from foreign countries are being examined by the USDA and others. Release of some of these control agents into the US are being seriously considered by the USDA. As part of this consideration, a risk-benefit analysis is made. Questions about introductions are not easy to resolve but require careful consideration by all stakeholders. In the US, importation of aquatic animals or plants is regulated by the USFWS and the USDA. The NAA supports the USFWS and USDA in these efforts.