SEA URCHINS AS BIOLOGICAL CONTROL OF “FOULING” IN A CULTURE OF NODIPECTEN NODOSUS (LINNAEUS, 1758) IN THE SANTA MARTA AREA, COLOMBIAN CARIBBEAN.

Abstract

We evaluated the effectiveness of sea urchins Lytechinus variegatus and Echinometra lucunter as biological controllers of “fouling” in culture of Nodipecten nodosus in Nenguange Bay, Santa Marta, Colombian Caribbean, collecting specimens with average sizes of 50 and 55 mm. Five treatments were established: 1) and 2) two and four individuals of E. lucunter per floor of pearl net; 3) and 4) two and four individuals of L. variegatus per floor of pearl net and 5) Control (without sea urchins). The scallops used in the study corresponded to the animals captured through artificial collectors installed in the station, with average sizes of 80 mm. The results showed a significant decrease in the following by sea urchins, but L. variegatus presented the highest reduction values (68 and 55 % on the pearl nets and valves, respectively) showing an increase in size and an increase in survival of N. nodosus. We identified a total of 25 individuals associated with the pearl nets and valves of N. nodosus, corresponding to seven taxonomic groups: Chlorophyta (1), Porifera (2), Mollusca (8), Annelida (3), Arthropoda (8), Bryozoa (1), and Pisces (2).