Impacts of exotic marine species at issue in Bates College lecture

Jim Carlton, a marine scientist at Williams College, will discuss the effects of exotic marine organisms on both the ecology of near-shore environments and the people who depend on those environments at 4:10 p.m. Tuesday, March 30, in Carnegie Science Hall, Room 204, Bates College, Campus Avenue.

Sponsored by the biology department, the annual William Sawyer Memorial Lecture is open to the public at no cost. For more information call 207-786-6490.

Carlton’s lecture is titled Marine Bioinvasions: The Interrelationships Between Marine Ecology, Maritime History and Marine Policy. Carlton will explain how human activities have led to the introduction of hundreds, perhaps thousands, of marine animals and plants into new environments worldwide over some 500 years. These invasions of exotic species, Carlton says, “have altered the biodiversity, community structure and habitats of near-shore environments globally.”

He will also touch on the societal and economic impacts of these invasions, and the public-policy issues that arise from non-native species introductions.

One of the most infamous exotic invaders in North America is actually a freshwater species, rather than a marine organism: the European zebra mussel. This prolific, voracious and tenacious mollusk has threatened fisheries, damaged infrastructure and reduced food supplies for native species in the Great Lakes and American rivers.

In Maine, the advent of invasive freshwater plants such as Eurasian and variable-leaf water milfoil has forced strict new precautions onto boat owners.

In the marine environment of the Gulf of Maine, invaders include the relatively harmless European green crab and Japanese sputnik weed — yet, Carlton told an interviewer in the summer 1998 issue of Gulf of Maine Times, “it’s only a matter of time until we register a front-page, major invasion in the Gulf of Maine. We are not able to predict what it will mean, so we’d rather it not happen.”

Carlton is professor of marine sciences at Williams College and director of the Maritime Studies Program of Williams College and Mystic Seaport. His research focuses on global marine bioinvasions and on marine extinctions in modern times.

Carlton is the founding editor-in-chief of the international journal Biological Invasions. In 1999 he was the first scientist to receive the U.S. government’s interagency Recognition Award for Significant and Sustained Contributions to the Prevention and Control of Nonindigenous Species in America’s Aquatic Ecosystems. He has testified seven times on invasive species before Congress.

Carlton’s lecture is made possible by the William Sawyer Memorial Fund. Dr. Carl E. Andrews, Bates class of 1940, established the William Sawyer Memorial Biology Lecture Fund to honor William H. Sawyer Jr., Bates class of 1913, who taught biology at Bates from 1916 to 1962.