Effects of tourist visitation and supplementary feeding on fish assemblage composition on a tropical reef in the Southwestern Atlantic

The effects of tourist visitation and food provisioning on fish assemblages were assessed by visual censuses (stationary technique) carried out in a tropical reef in Northeastern Brazil. Comparisons of species abundance, richness, equitability, and trophic structure in the presence (PT) and absence (AT) of tourists suggest that tourist visitation and supplementary food influenced the structure of the fish assemblage, as follows: (a) diversity, equitability and species richness were significantly higher on the AT period, while the abundance of a particular species was significantly higher during PT; (b) trophic structure differed between the AT and PT periods, omnivores being more abundant during the latter period, while mobile invertivores, piscivores, roving herbivores and territorial herbivores were significantly more abundant on AT. Reef tourism is increasingly being regarded as an alternative to generate income for human coastal communities in the tropics. Therefore, closer examination of the consequences of the various components of this activity to reef system is a necessary step to assist conservation and management initiatives

Population characteristics, space use and habitat associations of the seahorse Hippocampus reidi (Teleostei: Syngnathidae)

This paper provides a case study of a threatened seahorse species, Hippocampus reidi, highlighting the importance of using ecological information to assist conservation and management initiatives. Underwater visual sighting data (50 x 2m transect) gathered along the NE, SE and S portions of the Brazilian coast revealed an unequal distribution across localities, perhaps related to harvesting pressure, and a mean density of 0.026 ind.m-2. Our findings suggest some restricted spatial use by H. reidi, which was consistent with its estimated home range, and with re-sighting of specimens. Reproduction was recorded year-round, however productive peaks may exist. Components of habitat structure mostly used as anchoring points were mangrove plants, macroalgae, cnidarians, seagrass, sponges, and bryozoans. Conservation recommendations include: further characterization and mapping of habitats; assessment of availability and condition of microhabitats in selected areas, and studies on dispersal routes during initial life stages