January 1, 2019.
Leptasterias spp. is a species complex of small, six rayed, predatory sea stars that inhabit rocky intertidal communities along the Pacific coast of North America. A developmental mode of brooding their young, rather than broadcasting for planktonic development, limits dispersal away from the natal area, and may also result in fine scale local adaptation of populations. Local adaptation may lead to morphological and behavioral differences among populations, specifically towards the most available prey. Within the rocky intertidalthere are zones of high and low wave impact which create microhabitats with their own selective forces. In areas of high wave impact, stars experience the threat of dislodgement thus they adapt to holding on tighter to their substrate. This greatly impacts the ability of stars to get prey efficiently. One would expect to see that stars from different microhabitats specialize based on the prey abundant in their habitat. This laboratory study examined the prey preference of Leptasteriaspopulations from Palmers Point in Northern California. The purpose of the study was to 1) determine if sea stars have a preferred prey type and 2) determine if there is a difference in prey preference between stars of different microhabitats (i.e. in pools or attached to rocks within the rocky intertidal). To assess this, multiple binary choice trials were conducted in which sea stars were offered different prey types of equal accessibility. Preference was determined by calculating the average position of sea stars in a flume tank. Preliminary observations suggest that there is a difference in prey preference between stars of different populations and microhabitats, however not statistically significant. Future studies are necessary that include larger sample sizes, a more controlled laboratory environment, and field-based experiments and observations.
Biology | Ecology and Evolutionary Biology | Evolution | Life Sciences | Marine Biology | Population Biology | Terrestrial and Aquatic Ecology
C Sarah Cohen
Romberg Tiburon Center for Environmental Studies (RTC)
The 2019 STEM Teacher and Researcher Program and this project have been made possible through support from Chevron (www.chevron.com), the National Science Foundation through the Robert Noyce Program under Grant #1836335 and 1340110, the California State University Office of the Chancellor, and California Polytechnic State University in partnership with the Estuary and Ocean Science Center and San Francisco State University. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the funders.