Meeting Abstract
Amidst a rapidly changing climate, it remains important to understand the effects of natural environmental variation. The Bay of Panama experiences wind-driven upwelling during the dry season that is characterized by lower water temperature and higher salinity than the non-upwelling rainy season. Marine organisms that reproduce year round experience both of these conditions, but they may not be equally successful under both conditions. To study larval growth and survival in upwelling and non-upwelling conditions, we used larvae of the intertidal slipper snail, Crepidula cf. marginalis . Four environmental treatments were used as a 2×2 cross of high (34ppt) and low (30ppt) salinity with high (30°C) and low (24°C) temperature, which includes upwelling (high salinity, low temperature) and non-upwelling (low salinity, high temperature) conditions. We hypothesized that larval growth would positively correlate with temperature, be unaffected by salinity, and vary with parentage as well as that mortality would vary with parentage. Full-sibling families of larvae were each divided into 4 cups containing 30 larvae placed into each of the 4 treatments. On day 6, the live larvae were counted and preserved for imaging. ANOVA showed salinity, temperature, and parentage all had statistically significant effects on the survival of the larvae to day 6, as well contributing to the effects of interactions with parentage. Environmental conditions did matter for larval survival in our experiment, and the effect of specific environments on survival varied based on parentage. Thus, the significant effects of the environment on larval survival and growth depends heavily on their parentage, suggesting that significant effects of environmental conditions might be masked at a population level.
