Polychaetes from the Guarajuba coral reefs, Bahia, Brazil

Composition, distribution and feeding groups of polychaetes from the coral reefs of Guarajuba beach (Eastern Brazil) were examined to investigate their relationship with the present condition of the reefs. The organisms were randomly sampled from three zones: (1) the landward border of the top of an emergent reef (landward emergent reef - LER); (2) the seaward border of the same reef top (seaward emergent reef-SER); (3) the top of a submerged reef at 5 to 6 m depth (submerged reef-SR). Fifteen replicates of reef blocks (average 680 cm3 sample size) were collected from each zone, twice a year, making a total number of 90 samples. A total of 1754 individuals comprising 40 species were found. LER samples contained 405 individuals represented by 17 species. Perinereis elenacasoae was the dominant species (58%). SER samples consisted of 1184 specimens, and Eunice wasinensis (73%) was the most abundant of the 30 recorded species. The SR samples contained 165 individuals represented by 22 species, and Lysidice ninetta (52%) was dominant. Subsurface deposit-feeders dominated (LER = 86%, SER = 92% and SR = 73%), while carnivores, filter-feeders, surface deposit-feeders, and omnivores varied between 0.3 and 11%. The dominance by subsurface deposit-feeders indicate that changes occurred in the structure and function of the polychaete fauna as the reefs changed from a condition of growth to one of decay and erosion.