August 1, 2013.
Behavioral Variation Among Two Clades of Leptasterias spp.
Leptasterias spp. are six-rayed sea stars found along the rocky intertidal of the northeast Pacific Alaska to Santa Catalina Island, southern California. In central California, three clades of Leptasterias are found in separate or mixed populations, in diverse habitats that range from shallow pools of sea grass and algae to bare rock exposed to crashing waves. Two clades of Leptasterias were collected, Y-Clade from Mile Rock, San Francisco and L. aequalis from Pigeon Point, San Mateo to test for behavioral variation that may relate to habitat differences among clades. To measure differences in activity, the righting response was timed at both field sites and in the lab. Behavior related to feeding was additionally compared in the lab between the two populations using response to barnacle prey. It is hypothesized that stars living in sea grass and algae extend their arms and tube feet to move and collect food particles in the water. Stars living on rocks and within crevices may use their tube feet and arms to conform to the irregularities of the rock surface with a tight suction and feed directly on their prey. These experiments will provide measures of behavioral variation among the clades and help determine if behavioral variation may be a related to habitat or genetic differences.
Romberg Tiburon Center for Environmental Studies (RTC)
This material is based upon work supported by the S.D. Bechtel, Jr. Foundation and by the National Science Foundation under Grant No. 0952013 and Grant No. 0833353. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the S.D. Bechtel, Jr. Foundation or the National Science Foundation. This project has also been made possible with support of the National Marine Sanctuary Foundation. The STAR program is administered by the Cal Poly Center for Excellence in Science and Mathematics Education (CESaME) on behalf of the California State University (CSU).