There have been many invasions of foreign species into new territories. Asian carp may pose substantial environmental risk to the Great Lakes if they become established there, according to a bi-national Canadian and United States risk assessment released today. Bighead and silver carps — two species of Asian carp — pose an environmental risk to the Great Lakes within 20 years, with the risk increasing over time. Lakes Michigan, Huron and Erie face the highest risk relative to the other lakes. The new risk assessment report was led by the Department of Fisheries and Oceans Canada and included a team of scientists from Canada and the United States. Two U.S. Geological Survey scientists were among the co-authors of the report.