This paper reports the yellowline arrow crab, Stenorhynchus seticornis, acting as cleaner of longjaw squirrelfish, Holocentrus adscencionis moray eels Gymnothorax funebris, G. moringa, G. vicinus and squirrelfish Holocentrus adscencionis at two reefs in the Baía de Todos os Santos, Bahia State, eastern Brazil. We believe that other species of reef fish are potential ‘clients’ of yellowline arrow crab and that this activity occurs throughout its distribution.

The influence of the lunar phases and tidal range on the fish capture was analysed in a tidal flat in Barra do Paraguaçu (Baía de Todos os Santos). The sampling was realized in the flood tide and ebb tide of the spring (full moon) and neap (waning moon) tides, between June 2007 and May 2008. At all sampling occasions, two parallel drags were accomplished to the tidal flat, in the same direction of the current, in a 100 m long area marked on the beach beforehand, using a seine net of 15 m × 2.0 m with a mesh of 12 mm between adjacent knots. A total of 2312 fish specimens were captured (26.5 kg), belonging to 75 species from 45 families. The mean number of captured fish was significantly larger in full moon at ebb tides, while the mean weight in the captures was larger in ebb tides. There was significant difference in number of species, number of fish, richness and diversity between full and waning moons. The number of fish and biomass were significantly different between tides. Significant differences were found in community structure regarding trophic groups in relation to tide and moon, although the classic diversity indices did not capture this effect between tides. Furthermore, it was possible to identify preferences of occurrence related to the change of tide in dominant species.

We report the occurrence of a lone humpback whale (Megaptera novaeangliae) calf inside Baía de Todos os Santos, north-eastern Brazil, encountered swimming near the shore at a busy beach of the city of Salvador. The calf was monitored for over six hours during which time it was photographed performing an unusual behaviour, interpreted by the authors as a sign of stress and disorientation. One week later, a dead humpback whale calf was found 14 km north-east, on the island of Itaparica. Due to the similar size and the oceanographic currents of the area, we considered it to be the same animal. Finally, we discuss considerations to improve conditions for the rescue of cetaceans in the future.