Changing maximum and minimum water temperatures affect the recruitment and growth of invasive solitary (Ascidiella aspersa) and colonial (Botrylloides violaceous and Diplosoma listerianum) tunicates on the Connecticut coast of Long Island Sound. Didemnum sp. was not studied, but "
during the last 3 years
a didemnid ascidian, previously unknown to the western Atlantic (G. Lambert, personal communication) has become established at our study locations." (see p. 15500)
Source
Stachowicz, J.J., Terwin, J.R., Whitlatch, R.B., and Osman, R.W., 2002, Linking climate change and biological invasions: ocean warming facilitates nonindigenous species invasions, Proceedings of the National Academy of Sciences, v. 99, no. 24, p. 15497-15500. (PDF format)