What is the current population of clams in Hampton-Seabrook Harbor and how has it changed over time?
The most recent clam population in Hampton-Seabrook Harbor in 2015 was 1.4 million clams. The population has declined most years since 1997.
Clams may be limited by a type of cancer (Hemic neoplasia) that affects marine bivalves but is not dangerous to humans. Figure 15.2 shows that the percentage of clams infected with Neoplasia has increased since 2002. Research suggests there are several factors that make clams more susceptible to this disease, especially pollution (mainly heavy metals and hydrocarbons) and warming water temperatures.53
Green crabs eat clams and have also been shown to reduce clam populations. However, Figure 15.3 shows that green crab abundance in Hampton-Seabrook Harbor has steadily declined–for unknown reasons–between 2011 and 2015.