Impacts of Sea Star Wasting Syndrome on Larval Pisaster ochraceus: a pilot study on pathogen exposure

Abstract

A recent outbreak of sea star wasting syndrome (SSWS) along the U.S. West coast has decimated populations of many intertidal and subtidal sea star species. If populations are unable to recover quickly, SSWS is likely to cause significant changes to rocky intertidal and subtidal community structure and functioning in the Northeast Pacific ocean. Recovery will likely depend in large part on the success of larval recruitment, but the impacts of SSWS on larvae are unknown. We raised embryos and early stage P. ochraceus larvae in treatments of sea water that varied in filtration exposure to potential pathogens of SSWS. We assessed treatment impacts on larval survival development and larval size. We found a significant effect of water treatment and filtration level on two measures of larval survival. Further studies are needed to better understand the direction and magnitude of these and other effects of SSWS on larval fitness.