Assessment of the fisheries characteristics in southeastern Brazil: Moving towards a monitoring program to assess Franciscana bycatch in FMA 1b – northern Rio de Janeiro
Salvatore Siciliano, Davi C. Tavares, Jailson F. de Moura and Ana Paula M. Di Beneditto
International Whaling Commission
Incidental capture in fishing gear is the main source of anthropogenic mortality for small cetaceans worldwide involving a range of fishing gear such as gillnets, trawls and long-lines. The Franciscana dolphin (Pontoporia blainvillei) is a small odontocete inhabiting coastal waters of the Southwestern Atlantic Ocean. This species is considered the most threatened cetacean in South America. It is listed as Vulnerable in the IUCN Red List and in considered Critically Endangered in Brazil. The Franciscana range has been divided into four ‘Franciscana Management Areas’ (FMAs I to IV). FMA 1 corresponds to the northern portion of the species area of distribution and includes the coasts of the Brazilian states of Rio de Janeiro (RJ) and in Espírito Santo (ES). FMA 1 is geographically isolated from the remainder of the FMAs. Within FMA, two populations have been recently recognized; they are labeled FMA 1a and FMA 1b. Bycatch in gillnets is likely the greatest threat to Franciscanas of these two populations, but quantitative estimates of fishery- associated mortality are either not available (FMA 1a) or are older than 10 years (FMA 1b). Recent line transect aerial surveys sampled the range of the two populations (Danilewicz et al., 2012), but were unable to compute estimates of abundance in FMA 1a because an insufficient number of sightings were observed. For FMA 1b, a population of less than 2000 individuals was computed. This estimate suggests that mortality in gillnets is unsustainable if bycatch rates today are similar to those observed 10 years ago. This proposal aims to (1) conduct surveys to identify fishing villages in FMAs 1a and 1b, (2) assess the characteristics of the fisheries in these regions and (2) evaluate whether incidental captures of Franciscana and other cetacean species occurs. We expect to provide a report containing a description of the fisheries and identification of areas of risk for Franciscanas given knowledge of their current and historical distribution. The information in the report will be used to establish a monitoring program to estimate bycatch of Franciscanas in FMA 1a and FMA 1b.