Behavioral responses of seven species of asteroids to the asteroid predator, Solaster dawsoni (responses of asteroids to the predator Solaster dawsoni).

Abstract

Seven asteroid species common to the northern California coast were studied for their defensive responses to the predator Solaster dawsoni. The presence or absence of an escape response was used to predict whether or not these species were susceptible to predation from Solaster. Strong escape responses were displayed by Patiria miniata, Henricia leviuscula, Leptasterias hexactis, Pycnopodia helianthoides, and small Pisaster ochraceus. Subsequent capture and consumption of Patiria, Henricia, Leptasterias and small P. ochraceus were observed. Solaster attacked all Pisaster spp. tested, but Pisaster brevispinus and larger P. ochraceus protected themselves from predation by utilizing their pedicellariae against Solaster whenever contact occurred. Dermasterias imbricata appeared to be immune to predation by Solaster. Contact between these two asteroids failed to elicit a defensive response in the former or an attack by the latter asteroid.