What has happened to Marylandís
Mya arenaria, the soft-shell clam, once represented a significant fishery in Maryland, with annual commercial harvests of nearly 500,000 bushels from the 1950s to 1971.
The population, however, took a devastating hit from Tropical Storm Agnes in 1972 and never fully recovered. Harvests dropped to about 150,000 bushels from 1972-1985. After being infected with disease Ė DN -- in the mid-1980s, harvests rebounded to about 250,000 bushels annually. Then, in 1990 Marylandís soft-shell clam population was found to be infected with a parasite, Perkinsus spp. Since then harvests have plummeted, with recent landings well under 2,000 bushels a year.
DNR conducted concerted population and disease surveys since 2001, and both DN and Perkinsus spp. appear to be entrenched in Marylandís remaining softshell population. While restoration work has been considered, large-scale hatchery efforts would have to be combined with habitat manipulation, like oyster bars. Biologists do not believe the broadcast of seed clams could be successful without substantial protection from predators. In addition, the hatchery stocks would be subject to the same diseases as naturally occurring stocks -- as would clam strains from other locales.
- Mark Homer, Research Statistician
Illustration of Soft-shell Clam, courtesy of Joann Wheeler
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