The Nov. 8 issue of the journal Science will contain a paper in which University of Notre Dame researchers suggest a method of identifying invasive species that are likely to become nuisances if introduced into the Great Lakes.p. Invasive species, such as zebra and quagga mussels, present a significant economic and environmental threat to the Great Lakes, costing billions of dollars annually.p. David Lodge, a professor of biological sciences, and Cynthia Kollar, a former Notre Dame doctoral student, compared unsuccessful alien fish species with those that became successfully established in the Great Lakes through ballast water from ships or the aquaculture, bait, sport or pet industries. They sought to determine why some species flourish while others fail. They identified several characteristics that make a species successful at each stage (establishment, spread and impact) of the invasion process.p. Lodge and Kollar then compared the characteristics to those of species likely to be introduced purposely or in ballast water from the Black Sea region, a source of invasive species in the past. Their research identified 22 fish species that show the characteristics of successful invaders, including five that they predict will become nuisance invaders.p. Lodge and Kollar suggest steps that could be taken to prevent entry of these species, such as the treatment of ballast water and the prohibition of the importation of high-risk species for aquaculture, pet and live-bait industries. They also suggest that similar models could be developed to identify high-risk species among other groups of animals and plants.p. A member of the Notre Dame faculty since 1985, Lodge received his doctorate in ecology from Oxford University and his bachelor’s in biology from the University of the South.p. Kollar currently is a research fishery biologist with the U.S. Geological Survey.p.