Behavior and microhabitat selection of the tortoiseshell limpet Testudinalia testudinalis in the northwest Atlantic intertidal zone

In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: a b s t r a c t a r t i c l e i n f o Testudinalia testudinalis, the only species of intertidal limpet in the northwest Atlantic, feeds on the encrusting coralline alga Clathromorphum circumscriptum. We explored the behavior and habitat preference of this limpet in the intertidal zone of southern Maine and in laboratory experiments. We found T. testudinalis to be almost exclusively nocturnal, moving approximately 30-fold more during the night. This limpet did not home or display a consistent preference for any substrate as a resting site or preferred non-feeding habitat. However, they did show a significant preference for horizontal surfaces during feeding at night and vertical surfaces during the day. This behavior was observed at three intertidal sites along the Maine coast and in laboratory experiments, indicating a preference for a vertical resting site where heat stress, desiccation or predation may be less likely. The tortoiseshell limpet Testudinalia testudinalis Müller is a common inhabitant of the rocky intertidal and subtidal zones along the northeastern coast of North America (Steneck, 1982). Like other limpet species, T. testudinalis is limited by desiccation (Wolcott, 1973) These limpets are typically found in or near tide pools and are rarely seen on fully exposed rock surfaces (Wallace, 1972; pers. obs.). Though little work has focused specifically on T. testudinalis, these limpets are ideal study organisms because of their abundance, limited home range, and role as dominant grazers and structuring agents in marine communities (Steneck, 1982). The existence of T. testudinalis in the intertidal zone demonstrates its ability to withstand the stress and environmental variability of that habitat. The physical and biotic stresses of the intertidal zone (desiccation, osmotic stress, marine and terrestrial predation) are the driving forces behind habitat selection in intertidal gastropods These pressures force some species of limpets to select microhabitats such as crevices or vertical surfaces to avoid potentially deadly Several limpet species respond to these stresses by homing to a specific location on the substratum when not feeding or foraging (Jakob et al. Tightly attaching to a home scar serves as a means of predator avoidance and protects limpets from desiccation stress and wave …