Marine Advisors to Study Return of the Razor Clam

April 28, 2006

Contact: Christina S. Johnson, csjohnson@ucsd.edu, 858-822-5334

Clam digging is for many people part of the allure of the coastal experience. Humboldt County's Clam Beach, an aptly named gentle stretch of sandy oceanfront just south of Trinidad, was for many years a popular location for clam digging. But the predominant bivalve on this beach, the Pacific Razor Clam, suffered a population crash shortly after an El Nino event in 1982-83. "For all intents and purposes, they disappeared," said Pete Nelson, a California Sea Grant marine advisor in the region. "It's only in the last few years that they've begun to return."

RAZOR CLAMS

Credit: Long Beach Peninsula

Since there have been no formal studies on the razor clam population, scientists can only speculate on the clam's disappearance two decades ago and its sudden resurgence today. The disease Nuclear Inclusion X, which decimated populations in Washington and Oregon, is one possibility, although unproven. El Nino-induced oceanic changes may also be a factor.

This spring, Nelson and his fellow marine advisor in Del Norte County, Jim Waldvogel, will begin to collect information from clam diggers themselves. A sampling station will be set up periodically on Clam Beach and on South Beach in Crescent City for the advisors to measure clam shells and start building a base of knowledge about the razor clam population. Further studies may focus on cadmium levels, derived from natural sources or as pollutants, and on biotoxins like those that cause paralytic shellfish poisoning. Some biotoxins are associated with planktonic algae.

"We don't know what causes plankton blooms, but there is no question they are strongly influenced by oceanic conditions," Nelson said. The Pacific razor clam, found from Pismo Beach in Southern California to the Aleutian Islands in Alaska, is considered by many to be the finest food clam available from Pacific beaches.

For additional information about the Pacific Razor Clam study, contact Nelson at (707) 443-8369, panelson@ucdavis.edu.

NOAA's California Sea Grant is a statewide, multi-university program of marine research, extension services, and education activities. It is the largest of the nation's 30 Sea Grant programs and is headquartered at Scripps Institution of Oceanography at the University of California, San Diego. The National Sea Grant College Program is part of the National Oceanic and Atmospheric Administration (NOAA), U.S. Department of Commerce.