Distribution of Sea Urchins in Punta Dumalag, Matina Aplaya, Davao City

  • Marnie Grace I. Sonico University of Southeastern Philippines
Keywords: sea urchin, Punta Dumalag, distribution, diversity


This study investigated the distribution and diversity of sea urchins along the intertidal zone of Punta Dumalag, Matina Aplaya, Davao City. A total of 100 quadrats (1m x 1 m) spaced 5 m apart, in 3 transects laid perpendicular to the shoreline, recorded a total of 347 individuals, resolved into 5 species, namely, Echinometra mathaei (rock- boring or common sea urchin), Echinothrix calamaris (Hatpin urchin), Diadema setosum (long-spine or “tuyom”), Prionocidaris verticillata (rough spine urchin), and Diadema savignyi. Among the 347 individuals recorded, Echinometra mathaei was the most abundant in the site with a total of 286 individuals. Shannon-Weiner Diversity Analysis (0.602) suggests low species diversity. Physicochemical measurements such as water temperature, pH, dissolved oxygen, and salinity revealed that the study site is suitable for the culture of sea urchins.

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Author Biography

Marnie Grace I. Sonico, University of Southeastern Philippines

Natural Science Department, College of Arts and Sciences


Figure 1. A. Echinometra methai, common sea urchin collected in Punta Dumalag, Matina Aplaya, Davao City. B. Measurement of specimen. C-F. Different spicules of the species: C. tylote, D. sigma, E. chela, F. isochela micro-graphs taken at 100X using bright field microscope (Amscope).