Community Structure of Echinoderms and Their Surrounding in Segara Samuh Beach, Nusa Dua, Bali

Echinoderms are one genus of invertebrates that generally live in the form of polyps. The existence of echinoderms in a region illustrates the status of the area around them. Segara Samuh Beach is one of a variety of ecosystem areas in Bali Island where echinoderms are found. Since the limited information and the complex activities at Segara Samuh Beach make research about associations of Echinoderms with their surroundings, this research seems to be important to be conducted. This study was aimed at determining the density of species, species composition, and visual description of their surroundings. At the end of the study, we identified ten species of sea star (Asteroidea), one species of brittle stars (Ophiuroidea), one species of sea cucumbers (Holothuroidea) and three species of sea urchins (Echinoidea). Seastar (Asteroidea) is the most dominant species existed in Segara Samuh Beach. Every species had each surroundings characteristic, such as brittle rocks, sands, smooth sands, and smooth-rocks sands for Asteroidea, Ophiuroidea, Holothuroidea, and Echinoidea, respectively.