BIOEROSIÓN DE SUSTRATO ROCOSO POR ERIZOS EN BAHÍA MÁLAGA (COLOMBIA), PACÍFICO TROPICAL

Abstract

Sea urchins play an important role in the process of bioerosion of hard substrates in the marine benthos. Besides contributing to the disintegration of the substrate, this process provides space for the settlement of epifauna and may increase habitat complexity. There are no previous studies on bioerosion by sea urchins in the region of Bahía Málaga (Colombian Pacific). We estimated the bioerosion rates of three species of sea urchins (Centrostephanus coronatus, Diadema mexicanum, and Hesperocidaris asteriscus) by analysis of intestinal contents. For one species (Echinometra vanbrunti, N = 10) the intestinal turnover rate was determined, which was 10-12 h and did not match the assumed turnover rate (24 hours) used in previous studies. This suggests that these studies underestimated the rates of bioerosion by sea urchins. Although E. vanbrunti was significantly more abundant than other sea urchin species, D. mexicanum individuals were
larger and, therefore, the rate of bioerosion produced by this species was the highest. A positive relationship between bioerosion rates and the size of the sea urchins tests.