(Santa Barbara, Calif.) -- A paper that authors are calling a "home run" study on the spread of disease is published in this weeks issue of the Proceedings of the National Academy of Sciences (PNAS).
The study traces -- through genetic analysis -- the accidental introduction of invasive snails with parasitic flatworms. The invaders were probably transported with Japanese seed oysters imported into the waters of the Pacific Northwest over a century ago. It is the first comprehensive genetic analysis of an invasive marine host and its parasites. The study points to broad implications for identifying and mitigating spreading disease in a globalized economy.
Understanding the invasion pathways of disease-causing organisms and their hosts is key in limiting future disease outbreaks in humans, in agriculture, and in wildlife.
Co-author Armand Kuris, professor of zoology in the Department of Ecology, Evolution and Marine Biology at the University of California, Santa Barbara, is one of a handful of experts who have been studying the ecology of parasites since the 1960s, an area of research that Kuris reports is understudied because parasites are so often invisible. He calls this PNAS paper a home run because it describes a complete picture of biological invasions. He explained that the imported snail has wiped out the native snails, changing the ecosystems of the Northwest.
"Little did the American oystermen of the early 1900s know that their activities could impact local fisheries one hundred years later," said Kuris. "Oyster aquaculture brought in many exotic species, including clams, worms, and snails. Importation was done in a crude and sloppy manner; there was little government regulation of these things at the time."
Invasive North American populations of Asian mud snails, Batillaria attramentaria, probably arrived with Pacific oysters, Crassostrea gigas, imported from northern Japan in the early 1900s, a
Contact: Gail Gallessich
University of California - Santa Barbara