Can hard clam larval survival explain recruitment failure in GreatSouth Bay: A modeling study?

摘要

A biochemically-based model was developed to simulate the growth, development, and metamorphosis of hard clam (Merce-naria mercenaria) larvae. Larvae are simulated in terms of protein, neutral lipid, polar lipid, carbohydrate, and ash content. Initial biochemical content of the larva is determined by egg composition and changes in this occur as the larva grows and in response to the biochemical composition of available food. Simulations that used environmental conditions from Great South Bay, Long Island showed that variations in temperature and food quantity produce small changes in overall larval survivorship relative to that obtained from average conditions. The largest decrease in larval survivorship resulted from variations in the quality of food available to the larva. Reductions in food lipid content resulted in lowest larval survival rate. These results suggest that changes in food quality during the past decade may be a contributing factor to the present low recruitment rates of hard clam larvae in Great South Bay.