Effects Of Large Predators On The Field Culture Of The Hard Clam, Mercenaria mercenaria

Abstract

Individuals in the clam industry h ave used fences to keep the cownose ray, Rhirioptera bonasus, out of planted areas (Lewis 2 ; Burton3 ). Tiller et al. ( 1952) indicated losses due to skates in planted holding areas and stated that One man reported the loss of 600 bushels of small clams in two nights during 1948 .... Merriner and Smith4 stated that cownose ray predation is a serious problem on oyster and clam grounds in Chesapeake Bay. From these observations it is clear that such large predators could be a significant deterrent to the culture of clams from Delaware Bay southward along the Atlantic coast. The present study continues a program designed tv evaluate methods of protecting areas seeded with young Mercenaria mercenari