Comunidades y arrecifes coralinos del Parque Nacional Marino Ballena, costa del Pacífico de Costa Rica

Coral communities and reefs of Ballena Marine National Park, Pacific coast of Costa Rica Se estudiaron las comunidades y arrecifes coralinos del Parque Nacional Marino Ballena (PNMB), en el Pacifico sur de Costa Rica, mediante tres transectos por sitio, de 10 m de largo cada uno y paralelos a la costa, utilizando una cuadricula de 1 m2. Se encontro un total de 15 especies de corales (11 hermatipicas y 4 ahermatipicas), las que sumadas a informes previos para el parque hacen un total de 18 especies. El coral Porites lobata presento la mayor cobertura coralina (36.5 ± 3.7%) y fue el unico presente en todos los sitios. Las otras especies de coral presentaron bajas coberturas (<10%) y solo fueron observadas en pocos sitios. El porcentaje de coral muerto fue de 1.8 ± 0.6% y el porcentaje de blanqueamiento (0.7 ± 0.2%) esta dado por P. lobata en un solo sitio. El PNMB y la Isla del Cano poseen el mayor numero de especies de coral (18 especies) de la region sur de Costa Rica; sin embargo, difieren en su composicion. La baja diversidad y la baja cobertura coralina de varios sitios del parque se atribuyen al impacto del fenomeno de El Nino en los ultimos anos, a la sedimentacion y a la dilucion de las aguas en epoca de lluvias. Se sugiere la necesidad de realizar un monitoreo a largo plazo sobre estos ecosistemas y determinar futuras estrategias de manejo y conservacion. The coral communities and reefs at Ballena Marine National Park, on the southern Pacific coast of Costa Rica, were studied using three 10-m long transects per site, parallel to the coast, with 1-m2 quadrants. A total of 15 species of corals (11 hermatypic and 4 ahermatypic) were found, which when added to previous reports for the park makes a total of 18 species. Porites lobata showed the highest coral cover (36.5 ± 3.7%) and was the only species present at all sites. The other coral species had low coverage (<10%) and were observed in a few places. Dead coral had a cover of 1.8 ± 0.6% and the percent of bleached coral (0.7 ± 0.2%) was due to P. lobata at only one site. This park and Cano Island have the highest number of coral species (18 species) in the southern region of Costa Rica, but they differ in composition. The low diversity and low coral cover in the park is attributed to the impact of the El Nino phenomenon in recent years, to sedimentation and to the dilution of waters during the rainy season. We suggest that a long-term monitoring program of this ecosystem is needed to determine future management and conservation strategies.