Meeting Abstract
A clade of cryptic species of six rayed sea stars (Leptasterias spp). with limited dispersal potential are found in differing rocky intertidal habitats including protected pools and wave-exposed rocks. Field and laboratory performance tests were carried out with stars from pools and exposed rocks in Central California to test for behavioral differences associated with habitat type. It is hypothesized that individuals living on wave-exposed rock are less mobile because the selective focus is to hold tight to the rock to avoid being washed away. Conversely, sea stars from pool habitats are expected to show more flexible behavior as wave impacts are attenuated by pools. In this study, a careful methodology for field and laboratory comparison of behavior was developed and used to collect performance data on activity levels. Righting response, a standardized performance measure, was used for comparisons of rock and pool stars, and subsequently, stars were genetically barcoded to determine the phylogenetic clade composition of the habitat and behavior types. Pool stars were significantly faster in righting response in comparison to rock stars in field tests. Laboratory tests showed a similar pattern, and there may also be an effect of sea star size on righting response that was not detected in field comparisons. Barcoding revealed that there may be differences in clade composition between habitat types with the pool clade showing broader habitat distributions in comparison to the rock clade, compatible with greater activity measured in the righting response in the pool stars. These subtle variations in behavior or activity levels related to overlapping, yet differing habitat distributions, may help to explain the occurrence of multiple clades of cryptic Leptasterias spp. along the northeast Pacific coast.
