Tuesday, July 13, 2010

Killing invasive clams


Lake Tahoe scientists at the University of California, Davis, and the University of Nevada, working with government and conservation organizations, began a novel attempt last week to control the dime-sized Asian clam, which threatens lake clarity.


First observed in the lake in 2002, the Asian clam population in some places now has reached thousands per square yard, mainly along the California-Nevada state line in the southeast corner of the lake.


Once it takes hold, the Asian claim displaces native claims, snails and other organisms relying on the lake clarity, and they foster the growth of green algae, which impacts lake clarity. As well, the clams can foster the invasion of quagga mussels, according to scientists.


The effort to kill the claims involves installing an acre of rubber sheeting on the lake bottom to kill the clams by depriving them of oxygen. The sheeting will remain in place all summer.


That study and the results of this year's acre-scale experiment will be used to help Tahoe Basin agencies develop a clam management strategy.
(Photo: UC Davis)