Title

sea urchin Diadema antillarum Phillipi, 1845 influences the diversity and composition of the mobile mega-invertebrate community on rocky bottoms off the Canary Archipelago.

Document Type

Journal Article

Publisher

Universidad de Valparaiso

Faculty

Computing, Health and Science

School

Natural Sciences, Centre for Ecosystem Management

RAS ID

9203

Comments

This article was originally published as: Ortega, L., Tuya, F., & Haroun, R. J. (2009). The sea urchin Diadema antillarum Phillipi, 1845 influences the diversity and composition of the mobile mega-invertebrate community on rocky bottoms off the Canary Archipelago. Revista de biología marina y oceanografía, 44(2), 489-495. Original article available here

Abstract

The effect of the sea urchin Diadema antillarum density over the diversity and composition of the mobile megainvertebrate community (> 2 cm) inhabiting shallow rocky reefs off the Canary Archipelago (eastern Atlantic) is described. Specifically, it was predicted that (1) high densities of D. antillarum produce a low diversity of the mobile megainvertebrate community, and (2) the composition of this community changes between rocky bottoms (= reefs) under different densities of D. antillarum. The presence of megainvertebrate taxa, and the density of D. antillarum individuals were recorded visually using 2 x 2 m quadrats (n = 16 replicates) in each of 24 locations (three locations in each of the eight main islands of the archipelago), which were visited in four occasions between February-2003 and October-2004. Thritythree taxa of mobile mega-invertebrates were observed. We registered a decline in the richness of such assemblages with increasing densities of D. antillarum (rs = -0.20; P<0.001). Species richness fluctuated considerably (0-16 species) in those locations with low densities of D. antillarum (< 2 ind. m-2). However, species richness was always low (< 9 species) in those locations with high densities of D. antillarum (> 8 ind. m-2). A CAP ordination analysis showed significant differences in the composition of the mega-invertebrate community between rocky bottoms under different densities of D. antillarum, and we registered a negative correlation between the presence of some taxa and the densities of sea urchin. Consequently, the sea urchin D. antillarum influences the diversity and composition of the mobile mega-invertebrate community on rocky bottoms off the Canary Archipelago.

Access Rights

open access