Meeting Abstract

P3.15  Jan. 6  Dissolved organic matter and ultra-violet radiation influence the embryonic development of the sea urchin, Strongylocentrotus purpuratus HODGES, CORBIN*; WENDT, DEAN E.; California Polytechnic State University; California Polytechnic State University chodges@calpoly.edu

Many species of marine invertebrates can take up dissolved organic matter (DOM) but the ecological importance of DOM uptake remains largely unexplored. Of the studies that directly assess the putative ecological benefits of DOM, few, if any, examine the interaction between DOM uptake and abiotic factors such as UV radiation. This study examines the potential for DOM, as an energy and nutritional source, to reduce the deleterious effects of ultra-violet radiation on embryos of the sea urchin, Strongylocentrotus purpuratus. We also explored the relationship between DOM presence/absence and the timing of early embryonic development. We found that in the presence of DOM embryos complete first cleavage more quickly than in the absence of DOM. Our preliminary results show that S. purpuratus embryos in seawater with DOM took 5% less time to reach 50% cleaved than embryos in seawater without DOM. Our preliminary data also suggest that DOM can offset the negative effects of exposure to UVR. Cleavage delay normally observed after UV exposure was reduced by about 10% when DOM was present. Further work will explore the degree to which these trends occur in other species and whether the benefits last through later stages of development.