Coleta de equinodermos na Baía de Todos os Santos, estado da Bahia: o comércio aquariofilista

The ornamental marine trade has increased on a worldwide scale. Although Brazil is amongst the major exporters, data about this activity are underestimated. Therefore, the profile and consequences of such activity to the wild populations are not fully understood. In spite of being basically supported by fish collection, charismatic invertebrates also figure in this trade and virtually nothing is known about the echinoderms harvested in Brazil. Since baseline data are scarce, this study aims to provide an initial assessment on the marine aquarium echinoderm trade in Bahia State, northeastern Brazil, evaluating the landing of these animals during a ten-year period. Echinoderm landing was monitored and the trade profile was investigated from January 1996 to December 2005. The trade involved five economic segments and supplied not only the local market but other Brazilian states and countries such as Argentina. Fifteen species were commercialized and, amongst them, threatened echinoderms included in the National Red List. Fishermen usually captured them by hand but destructive methods were also used. For these reasons, studies on the dynamics of harvested populations and the development of public policies are urgently needed in order to allow the sustainability of this trade.O comércio ornamental marinho tem crescido em escala mundial. Apesar do Brasil estar entre os maiores exportadores, dados sobre esta atividade são subestimados e, portanto, seu perfil e consequências às populações não são totalmente entendidos. Ainda que seja sustentado pela coleta de peixes, invertebrados carismáticos também figuram neste comércio e praticamente não há informações sobre os equinodermos coletados no Brasil. Dada a escassez de dados, este estudo teve como objetivo prover uma avaliação inicial do comércio de equinodermos pra o aquariofilismo marinho no estado da Bahia, Nordeste do Brasil. O desembarque de equinodermos foi monitorado e o perfil do comércio investigado de Janeiro de 1996 a Dezembro de 2005. A atividade envolveu cinco segmentos econômicos e abasteceu não apenas o comércio local, mas outros estados brasileiros e países, a exemplo da Argentina. Quinze espécies foram comercializadas, entre elas, equinodermos incluídos na Lista Vermelha Nacional de organismos ameaçados. Pescadores normalmente os coletavam manualmente, no entanto, métodos destrutivos também eram utilizados. Assim, estudos sobre a dinâmica das populações coletadas e o desenvolvimento de políticas públicas que regulem esta atividade são urgentes, a fim de permitir a sustentabilidade deste comércio

Descrição histológica de gônadas de traíra Hoplias malabaricus (Bloch) (Osteichthyes, Erythrinidae) da barragem do rio Gramame, Alhandra, Paraíba, Brasil Histological description of the gonads of the traíra Hoplias malabaricus (Bloch) (Osteichthyes, Erythrinidae) from the Gramame River Reservoir, Alhandra, Paraíba, Brazil

<abstract language="eng">The reproductive cycle of Hoplias malabaricus Bloch, 1794, was studied through histological preparations, based on 102 specimens collected in the Gramame reservoir, Paraiba State, from August 1993 to July 1994. Seven developmental stages were identified for the feminine gametes and five for the masculine gametes

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