Abundance and distribution of Echinometra lucunter (Echinodermata, Echinoidea) at a rocky platform on the central coast of Venezuela

Abstract

Echinometra lucunter is a common Caribbean sea urchin, which the abundance and distribution were evaluated along a rocky platform at Cepe beach, Venezuela. Two surveys were conducted along transects perpendicular and parallel to the coast, from the shore to the wave breaking zone (WB), using 1m2 quadrat method. In survey-1 the smaller sea urchins (<1.8 cm) occurred in the tide pool zone (TP) and medium and large dominated in the WB. The average density recorded in the WB and TP (140.2 and 272.7 ind/m2 respectively) are among the highest values reported in the Caribbean. The maximum density recorded was 562 ind/m2 in the TP and most of them were juveniles (<1.8 cm). In survey-2 sea urchins (³3.0 cm) density ranged from 1 to 156 ind/m2 and the overall average was 29.6 (± 32.4) ind/m2. The highest density occurred in the platform western sector (average 43.2 ±41.3 ind/m2). In the transects parallel to the coast the sea urchin's abundance gradually decreased from the WB (130 ±12 ind/m2) towards the coast (0.3 ±0.37 ind/m2). In conclusion, the E. lucunter densities recorded on the Cepe beach platform are the highest values reported in the Caribbean.