Observations and Experiment:

Morphologies and Life History

Native vs. Invasive

Tunicates in Immunology

Organisms of the Intertidal Zone

Photo Galleries:


The rocky intertidal zone in Nahant, MA, is home to Botryllus schlosseri and Botrylloides violaceus, two introduced sessile organisms. These filter feeders can be found across the globe. Their habitats range from the harsh conditions of New England shores, to calm marinas in the Mediterranean. Anthropogenic activities such as boat hull fouling, interoceanic trade, and aquaculture industries are the cause of this extensive range. Artificial structures in harbors where boats may dock are prime locations for invasive ascidians to colonize. These substrates and conditions, however, are not always similar to those of the rocky intertidal zone.

This field study project was a set of observations on preferred substrate settlement of Botryllus schlosseri and Botrylloides violaceus, as well as observations on whether temperature of the water influenced growth of colonies between September and November of 2006. The information recorded stimulated further questions and literature research on invasive and native ascidian species.