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We compared the reef fish assemblages of two habitats, coral reefs and coral communities (rocky substratum with coral colonies), in the Las Perlas Archipelago in Pacific Panama and attempted to determine associations with habitat variables. We used a modified Atlantic and Gulf Rapid Reef Assessment (AGRRA) survey to record fish species and quadrat transects to determine benthic composition. Multivariate non-parametric multi-dimensional scaling (MDS) ordinations were performed in PRIMER and univariate correlations were used to determine relationships. The reef fish of coral communities were significantly more diverse and species rich than those of coral reefs. The two habitats had significantly different species and size composition, but trophic and family groups overlapped between habitats. Topography, exposure, and the percentage cover of branching and massive corals correlated significantly with differences in fish parameters. The reef fish assemblages of this region appear to be determined more by the larger scale structural features that characterize the two habitats than by features that vary over small scales within the habitats.Keywords: fish, coral, reef, composition, habitat, diversity I N T R O D U C T I O NFish species interact closely with their habitat for the majority of their lives (Jones & Syms, 1998) and therefore, there is reason to hypothesize that the distribution and structure of reef fish communities should correlate with variables of the habitats present (McGehee, 1994;Ö hman, 1998). Factors previously found to influence reef fish community structure include benthic diversity, habitat complexity, live coral cover, macroalgal cover, depth and exposure. Topographically complex reef habitats or those with high numbers of growth forms or high benthic diversity should provide more microhabitats, refuge sites, and food resources for a higher number of individuals and species. Research in the literature supports this in general, with positive relationships being found with fish diversity, species richness and abundance (Luckhurst & Luckhurst, 1978;Carpenter et al., 1981;Ault & Johnson, 1998;Lara & Gonzalez, 1998;Ö hman & Rajasuriya, 1998;Lirman, 1999;Nagelkerken et al., 2000;García-Charton & Pérez-Ruzafa, 2001;McClanahan & Arthur, 2001;Friedlander et al., 2003;Dominici-Arosemena & Wolff, 2005Espinoza & Salas, 2005;Gratwicke & Speight, 2005a;Brokovich et al., 2006;Kuffner et al., 2007).Live bottoms offer food sources and often higher structural variability and shelter (Huntsman & Waters, 1987) and positive relationships have been found between live coral cover and reef fish diversity, richness and abundance (Bell & Galzin, 1984;Bouchon-Navaro & Bouchon, 1989;Chabanet et al., 1997;Connell & Kingsford, 1998;Jones et al., 2004;Bozec et al., 2005) with declines in fish communities found after coral cover loss (Wilson et al., 2006(Wilson et al., , 2008, although this was not found in other studies (Roberts & Ormond, 1987;Chapman & Kramer, 1999;Lecchini et al., 2003). Williams & Polunin (2001) reporte...

SUMMARYThe protected sites defined under the Marine Conservation Corridor of the Tropical Eastern Pacific (MCCTEP) include most of the endemism and a fraction of the areas of high diversity for reef corals and fishes. Although those areas are connected biologically over distances >600 km, lack of large-scale sampling and attention to taxa other than scleractinian corals has limited the protection of shallow coral reef and coral community habitats in some areas of the Tropical Eastern Pacific (TEP) region, particularly non-offshore islands in Ecuador, Panama and Costa Rica. The newly created Las Perlas marine protected area (1688 km 2 ), the second largest archipelago in the TEP, fills a regional conservation gap for the protection of reefs and potentially becomes the second highest coral diversity area in the MCCTEP. This study describes the distribution of live coral cover and species alpha-diversity over 307 ha of shallow coral reefs and coral communities in the Las Perlas Archipelago. Nineteen scleractinian and 38 octocorals were observed, including species previously thought to be uncommon. Although coral communities generally had a greater number of species than coral reefs, species richness did not differ between habitats. However, their coral and octocoral composition and benthic makeup (coral cover, macroalgae, sponge, etc.) differed. The reefs had higher live coral cover (61.2%) and lower algal cover (32.5%) than the coral communities (26.0% and 65.7%, respectively). Octocorals were more common in the communities than on the reefs. There was a negative relationship between live coral cover and species richness, low to moderate cover generally coinciding with coral community sites and higher species richness. Areas are recommended for marine reserve zoning within the new Las Perlas marine protected area to ensure the protection of important * Correspondence: Hector M. Guzman Tel: + 507 212 8733 e-mail: guzmanh@si.edu habitats and maintenance of diversity in the TEP, both highlighting the importance of the southern islands of the archipelago for coral diversity and the northern islands for their high live coral cover. Review of the representativeness of regional coral diversity would facilitate better design of small-scale reserves across the TEP, following comparable survey methods.