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We report the first record of two teleost species from two archipelagos in the western equatorial Atlantic. We recorded the occurrence of Cantherhines pullus (Ranzani, 1842) (Monacanthidae, Tetraodontiformes) from the Fernando de Noronha Archipelago, a group of volcanic islands 345 km off the northeastern coast of Brazil. We also report the first regional record of Hemiramphus brasiliensis (Linnaeus, 1758) (Hemiramphidae, Beloniformes) from the Saint Peter and Saint Paul’s Archipelago, which is a small and isolated group of rocky islands 520 km from the Fernando de Noronha Archipelago on the Mid-Atlantic Ridge.

The objective of this study was to record the occupation of spinner dolphins at the northeastern end of the Fernando de Noronha Archipelago -a new occupation area. Data indicates that the area of the Inter Islands is the one in which the spinner dolphins present a longer permanence, defining a new pattern of occupation, with an annual tendency to stay for longer periods in the region. This change of permanence area may be related to the increase of tourism in Fernando de Noronha. The study points to the area of the Inter Islands as crucial for the conservation of spinner dolphin habits in the Fernando de Noronha Archipelago.

We present an overview of predator-prey and other trophic relationships of spinner dolphins (Stenella longirostris) around Fernando de Noronha Archipelago, off northeastern Brazil, with use of original data and a brief review of data published elsewhere. Records were made while snorkelling among the dolphins in daytime. Individual fish pursuit and coordinated school herding were the two hunting tactics recorded. Three small prey types (oceanic squids, fishes, and prawns) were recovered from vomits collected in situ and from stomachs of two stranded dolphins. In their turn, spinners were preyed on by the cookiecutter sharks (Dalatiidae) as evidenced by round and crater-like wounds and circular scars. Additionally, the dolphins were preyed on by large sharks (Lamnidae, Carcharhinidae), as evidenced by crescent-shaped wounds and scars. Unidentified fishes bit fin pieces, as evidenced by variably-shaped marks. On the other hand, dolphins’ particulate faeces, vomits and live roundworms were eaten by plankton-feeding fishes. Thus, the trophic role of the spinner dolphins of Fernando de Noronha may be summarised as that of : 1) a predator of small oceanic squids, fishes, and prawns; 2) a prey for the small, piece-eating cookiecutter sharks and other unidentified fishes; 3) a prey for large sharks able to kill a dolphin; and 4) a particulate food supplier for plankton-eating fishes. Presentamos aqui una visón general sobre las relaciones tróficas de los delfines rotadores (Stenella longirostris) en el Archipiélago de Fernando de Noronha, noreste de Brasil. Las observaciones fueron hechas en periodo diurno, en buceo libre. La persecución individual a peces y el cercado coordinado en grupo, fueron las dos técnicas de caza registradas. Tres tipos de presas (calamares, peces y camarones) fueron identificados en vómitos in situ y en los estómagos de dos delfines encallados. Por otro lado, los delfines rotadores fueron depredados por tiburones cigarro (Dalatiidae), como fue evidenciado por heridas en forma de cráter y cicatrices circulares. Los delfines fueron también depredados por tiburones de gran tamaño, como fue evidenciado por mordeduras y cicatrices. Peces no identificados mordieron aletas, como fue evidenciado por las diversas formas de las marcas. Partículas procedentes de las heces y de vómitos así como vermes de los delfines fueron usadas como alimento por peces. El papel trófico de los delfines rotadores puede ser así sintetizado: 1) predador de calamares, peces y camarones; 2) presa de pequeños tiburones y de otros peces que retiran pequeñas porciones de tejido; 3) presa de grandes tiburones; 4) proveedor de partículas alimenticias para varias especies de peces planctófagos.

São relacionadas as 60 principais espécies vegetais dominantes do Arquipélago de Fernando de Noronha, no Nordeste brasileiro: 33 herbáceas, 12 lenhosas baixas (< 2 metros) e 15 lenhosas altas (> 2 metros). A partir de tratamentos numéricos analíticos, as informações mútuas para cada espécie em relação a variáveis ambientais evidencia grupos ecológicos distintos, caracterizados por seus padrões de repartição espacial. As plantas com padrão de repartição espacial definido dividem-se em espécies ubiquistas, de sotavento, de barlavento, costeiras, de áreas interiores, de áreas florestadas e de ocorrência isolada. As plantas com padrão pouco definido são classificadas mais por sua função na paisagem que pelo modo de repartição espacial nas ilhas e ilhotas. São as jitiranas, as invasoras e as espécies plantadas ou ornamentais. This paper relates the 60 main dominant plant species of the Fernando de Noronha Archipelago, on the Brazilian Northeast. Using analytical numeric treatments, the mutual information indexes were calculated for each species regarding to environmental variables. The results allowed the identification of seven groups of plants with defined patterns and three groups with less defined patterns of spatial distribution. The plants with defined patterns were divided into ubiquitous plants, species of windward and leeward coastal zones, interior and forested areas and isolated plants. The species with less defined spatial patterns were classified by their function on the islands landscape.