Sponge Physioecology On Moorea, French Polynesia: Local Distribution And Filtration Efficiency Of Lamellodysidea Under Varying Temperatures

Abstract

This physio-ecological study investigated the physiology and distribution of Lamellodysidea sp. in Moorea, French Polynesia. Specifically, its distribution was described across three reef types--fringing, mid-barrier, and barrier reefs--as well as across sites between Cooks Bay and Opunohu Bay. Additionally, filtration experiments were conducted to test how temperature impacts filtration efficiency. This is informative when predicting how future ocean temperatures are going to affect sponges success and distribution. Sponge abundance was found to decrease from the fringing reef out to the barrier reef, with the highest number of sponges in the fringing reef, less in the mid-barrier reef, and none found in the barrier reef. Sponges were also unevenly distributed across sites, with sponge abundance clearly increasing as you move away from Cooks Bay. Together, these data show that sponges demonstrate habitat preference that is related to their physiological tolerances. Filtration data showed that over a 3-hour period sponges increase their physiological output when introduced to environments 3-6 degrees Celsius above normal. This suggests that as ocean temperatures warm, sponges are likely to increase their filtration efficiency, thus increasing their ecological role as filter feeders, or struggle to survive at this new level of physiological function.