Skyrocketing numbers of invasive non-native fishes in the nation's waters are increasingly threatening aquatic systems, according to three USGS biologists writing in a book recently published by the American Fisheries Society.
The book, Nonindigenous Fishes Introduced into Inland Waters of the United States, provides a wealth of current information on the status and impacts of non-native fish in America's waterways.
For example, the authors write, non-native fish species are causing declines in the abundance and genetic integrity of native fish species -- including highly valued game and fisheries species -- and are probably an important factor in the extinctions of many of our native fish species.
The spread of non-native plants and animals has become a serious problem both in the United States and worldwide. A number of resources are being mobilized to address this issue, particularly following the recent signing of a presidential executive order on invasive species.
Non-native, or nonindigenous, species, are those which have established populations outside their native range. Many non-native fish in the United States were introduced by deliberate stocking, others have spread through releases of live bait or unwanted aquarium pets, or arrived in ballast water discharged from ships.
The new book provides detailed information on more than 500 non-native fish species, including methods of introduction, ecological and economic impacts, range maps and identification aids. "It represents the state of our current knowledge of nonindigenous fishes, and fills a large void by consolidating previously scattered information," says co-author Dr. Leo Nico, a biologist with the USGS Florida Caribbean Science Center in Gainesville, Fla.
Over the past 50 years the number of introductions of non-native fishes has
increased dramatically as a result of the rapid expansion of travel and
international shipping, as well as the increased interest in the a
Contact: Jim Williams
United States Geological Survey