Commercial aquaculture of the hard clam, Mercenaria mercenaria, is practiced throughout the Atlantic coast of the United States. The development of this industry is based on hatchery produced seed. Growout success is dependent on the initial size of the planted seed, predator protection and the timing of that planting. Seed placed in the field late in the planting season yields variable success. The reasons for the variable success of these late plantings has not been investigated, but is believed to be related to the "health" or "condition" of the seed. A second, but related source of economic loss is the variable success experienced when small clams are overwintered in onshore nursery systems. Once seed begin to die, losses can be at a rate of 5% or more per day compounded. Such losses impose a large economic burden on clam culturists. The researchers propose developing and testing a method that could be used by hatcheries or planters to evaluate the general "condition" of seed clams. This technique, once calibrated, could be used to make economic decisions on supplemental feeding or other techniques to improve condition of the seed.
