Species Profiles: Life Histories and Environmental Requirements of Coastal Fishes and Invertebrates (South Atlantic - Hard Clam

摘要

Species profiles are literature summaries of the taxonomy, morphology, range, life history and environmental requirements of coastal species. They are designed to assist in environmental impact assessment. The hard clam, Mercenaria mercenaria, supports an important commercial fishery in the South Atlantic, averaging about 1 million kg of meats annually from 1979 to 1983. It also is an important constituent of estuarine systems throughout the region. Spawning occurs in the spring and the fall at 16 to 30C. Planktonic eggs and larvae are carried by water currents, and larvae set sometime after 6 days of age. Mortality is highest in egg and larval stages, the most sensitive part of the life cycle. Spat display gregarious setting behavior and appear to select sand over finer substrates.