UPI - Biological invasions seen as major threats, new research shows

Invasive species get less attention than natural disasters but may be as economically damaging and warrant corresponding action, North American researchers say.

Writing in the journal BioScience, the researchers note species invasions are becoming more frequent worldwide, largely because of international trade. They say although many alien species establish themselves in a new location without causing significant harm, that's not always the case, a release by the American Institute of Biological Sciences reported Friday.

When the Nile perch invaded Africa's Lake Victoria, it contributed to the extinction of 200 fish species, biologist Anthony Ricciardi of McGill University and his co-authors said. And such invasions can also have huge financial impacts: the destruction of ash trees by the emerald ash borer is predicted to cost the United States $10 billion over the next decade, they said.