Ecology of the Northern Sea Star
(Asterias vulgaris)
Seastar Biology
Taxonomy
Life History
Echinoderms
Rocky Intertidal
The Study
Introduction
Methods
Results
Discussion
Picture Gallery
Bibliography and Weblinks
Glossary
Abstract
The northern seastar, Asterias vulgaris, is one of the most recognizable organisms inhabiting the rocky intertidal region of the Gulf of Maine. The seastar plays an extremely important role as a keystone species in the intertidal, encouraging diversity by limiting the distribution of the dominant competitor, the blue mussel Mytilus edulis. The northern seastar tends to migrate away from the intertidal and into deeper waters of the subtidal region during the onset of winter to avoid extreme temperature fluctuations and harsh conditions that occur during winter months. In this study, I surveyed the rocky intertidal coast at Nahant, Massachusetts to gain a better understanding of seastar distribution and abundance. Data was collected once a month for three months, from September through November, in which I recorded seastar densities and distribution. The results I obtained are consistent with other studies, showing that seastars do indeed tend to migrate into deeper waters in response to approaching winter months.
