Biology Commons^™

Behavioral Variation Between Two Clades Of Leptasterias Spp., Ashley N. Contreras

STAR Program Research Presentations

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 seagrass and algae to bare rock exposed to crashing waves. Initial field observations of two clades from different locations suggested that behavioral variation may relate to habitat differences among clades. To measure differences in activity, the righting response was timed at both field sites. As a result of behavioral variation observed in the field, more …

Temporal Variation In Larval Release In Botrylloides Violaceous, Damion J. Delton, Sarah Cohen

STAR Program Research Presentations

Despite Botrylloides violaceous being a globally invasive species in temperate marine habitats, little is known about it’s natural dispersal behavior. Previous work (Delton et al, 2011) suggests behavioral inferences based on a related and much more commonly studied species may not be appropriate, potentially due to a large size difference between the non-feeding larvae of these two species. Here, we consider factors that may affect dispersal potential. To study how light affects larval release, we measured timing of larval release in the field and compared larval size and time of release. Colonies were collected from floating docks in Richmond, CA …

Leatherback Hatchling Fitness, Violet Campbell, Shane Morales, Kelly Stewart

STAR Program Research Presentations

Leatherback hatchling fitness on land is essential for their success in entering the ocean without being predated. Two ways fitness on land may be measured are by how fast hatchlings crawl as well as how fast their righting responses are when they are flipped onto their carapaces. Hatchlings from certain nests have slower righting response times along with slower crawl times, both of which would increase the odds of predation and hinder the success of hatchlings reaching the ocean.

Hatchling crawling speed was determined by timing 12 randomly selected hatchlings from each nest to crawl a distance of two meters. …