Meeting Abstract

46.2  Monday, Jan. 5  Chronic occurrence of disseminated neoplasia in different populations of Mya arenaria in New England. BOETTGER, SA*; ROWLEY, BD; WALKER, CW; West Chester University; University of New Hampshire; University of New Hampshire sboettger@wcupa.edu

Disseminated neoplasia in bivalve mollusks is characterized by mitotic hemocytes with a nuclear to cytoplasmic ratio of 1:1. Efforts to link environmental contaminants to the initiation of this fatal disease have depended on data collected followed episodic contamination events. No studies have characterized the prevalence of this cancerous disease in sites with different pollution levels/concentrations over an extended period of time. Here we examine the prevalence of a disseminated neoplasia in the soft shell clam, Mya arenaria, at numerous sites in New England where clam fisheries have been negatively impacted and provide the first evaluation of clam neoplasia at three sites over a period of five years. Our surveys document the highest frequency of neoplasia in Mya arenaria in New Bedford Harbor in December (9.49% + 0.78), when seawater temperatures were low and the lowest frequency in July (1.082 + 0.4) at high seawater temperatures. These results may indicate vulnerability of neoplastic clams to increased temperature and oxidative stress. Based on shell measurements and a theoretical mathematical age model, we point out that Mya arenaria is susceptible to this disease only between one and two years of age when clam populations begin reproducing (33.5% at age 1 year and 62.57% at age 1.5 years). (Saltonstall/Kennedy NA08NMF4270416 to CWW)