Meeting Abstract

47.5  Saturday, Jan. 5  The Effects of Climate Change on the Immunocompetence of the Caribbean Sea Fan Coral MANN, W*; BURGE, C; MYDLARZ, L; The University of Texas at Arlington; Cornell University; The University of Texas at Arlington wtmann@uta.edu

Effects of climate change have been shown to negatively affect a multitude of organisms causing increases in disease prevalence, mortality, and ultimately changes to the biodiversity and structure of ecosystems. This is especially true for coral reefs. We hypothesize that the effects of climate change, such as elevated sea surface temperatures are compromising the immunity of corals leading to disease outbreaks. In this study, we examined the immunocompetence of the Caribbean sea fan coral, Gorgonia ventalina under natural and experimental temperature stress. Naturally stressed sea fans were collected during an abnormally warm year (2010) where temperatures remained elevated (>29°C) for 12 weeks or longer. To examine short term thermal stress, sea fans were also exposed to elevated temperatures in the lab for a period of 18 days. Immune responses were quantified using a suite of biochemical assays examining antioxidant, antimicrobial, protease inhibitor and melanization activity of crude protein extracts. Both experiments exhibited significant decreases in the various measures of immunity with the natural temperature stress having the most dramatic effect. Considering the increase in disease prevalence of corals, the data suggest that elevated sea surface temperatures are affecting the immunocompetence in corals that may lead to disease susceptibility. With the current trends of climate change, where temperatures are expected to continue increasing, incidences of coral disease and mortality rates are likely to continue increasing. It is imperative to continue to look at effects of climate change on corals in order to develop mitigation and management tools for coral reef conservation.