Survey for Leptospira and Brucella in Amazonian manatees, Amazon river dolphins, and a tucuxi in the Brazilian Amazon.

Leptospirosis and brucellosis are zoonotic diseases with global distributions that represent severe hazards to humans and animals. We investigated exposure to Leptospira spp. and Brucella spp. in samples from Amazonian manatees Trichechus inunguis, Amazon river dolphins Inia geoffrensis, and a tucuxi Sotalia fluviatilis. The animals were free-ranging or undergoing in situ rehabilitation in the mid-Solimões River region, Brazilian Amazon. Serum samples from 19 Amazonian manatees were tested by microscopic agglutination test, Rose Bengal test, and 2-mercaptoethanol Brucella agglutination test. Antibodies against Leptospira spp. were detected in 63% of the manatees tested and serovar Patoc was considered the infecting serovar in all positive samples. Titers were generally low, indicating chronic exposure, but higher titers indicative of an active infection were detected in 3 animals. Anti-Brucella spp. antibodies were not detected. Tissue and/or body fluid samples from 12 Amazon river dolphins, a tucuxi, and 2 Amazonian manatees were investigated by multiplex PCR and bacteriology for Leptospira spp. and Brucella spp. All samples were negative. However, Enterococcus faecalis was isolated from uterine fluid, lymph node, and lung of 3 Amazon river dolphins. Bacillus spp. were isolated from milk and synovial fluid from 2 Amazon river dolphins and from a milk sample from 1 Amazonian manatee. Knowledge of the pathogens present in Amazonian manatees, Amazon river dolphins, and tucuxis is of great relevance to species conservation and environmental health. Although no clinical signs were noted, further research is needed to elucidate the clinical relevance of infection by Leptospira sp. serovar Patoc in Amazonian aquatic mammals.

When You Get What You Haven't Paid for: Molecular Identification of "Douradinha" Fish Fillets Can Help End the Illegal Use of River Dolphins as Bait in Brazil.

The fishery for Calophysus macropterus, an Amazonian necrophagous catfish, is highly detrimental to river dolphins and caimans, which are deliberately killed for use as bait. In the Brazilian Amazon, this fishery has increased over the last decade, in spite of the rejection of scavenger fishes by Brazilian consumers. It was suspected that C. macropterus fillets were being sold in Brazilian markets, disguised as a fictitious fish (the "douradinha"). We collected 62 fillets from "douradinha" and other suspiciously named fish from 4 fish-processing plants sold at 6 markets in Manaus, in the Brazilian Amazon, and sequenced the cytochrome b gene to identify fillets to species. Sixty percent of fillets labeled "douradinha" or with other deceptive names were actually C. macropterus. Six other fish species of low commercial value were also found. The presence of dolphin tissue in the stomach contents of C. macropterus was confirmed by mtDNA control region sequencing. Our results formed the scientific basis for a moratorium on the fishing and fraudulent selling of C. macropterus, issued by the Brazilian Ministries of the Environment and Fisheries. Exposure of this fraud via the mass media can help end the illegal use of dolphins as bait in Brazil.

Feeding habits of Sotalia fluviatilis in the Amazonian Estuary- DOI: 10.4025/actascibiolsci.173 / Hábitos alimentares de Sotalia fluviatilis no estuário amazônico - DOI: 10.4025/actascibiolsci.v28i4.173

In this paper we present an analysis of the fifty S. fluviatilis feeding habits in the Amazonian Estuary. Animals were bycaught by the artisanal fishing fleet between 1996 and 2001. Feeding habits were analyzed by prey occurrence frequency (%F) and number percentage and stomachs contents preys similarity between marine and freshwater fish species present in the Amazonian Estuary. Thirteen fish species were identified (%F= 86.6), the most significant families were Sciaenidae (32%), Trichiuridae (26%) e Ariidae (16%), and four crustaceans species (%F=26). S. fluviatilis feeding habits did not differ by gender and in general, calves had higher prey diversity than juveniles and adults. The similarity was high (0.89) between estuarine S. fluviatilis feeding habits and the fishes species present in the Amazonian Estuary when the environment is mostly marine.

Objetivou-se descrever e analisar os hábitos alimentares de 50 golfinhos Sotalia fluviatilis capturados acidentalmente na frota pesqueira artesanal do Estuário Amazônico entre 1996 e 2001. As presas foram identificadas e calculadas a freqüência de ocorrência e numérica; testada a similaridade entre a diversidade de presas dos conteúdos e a diversidade de peixes marinhos e de água doce do estuário e, comparados os hábitos alimentares por sexo e categoria de maturidade. Ocorreram 13 espécies de peixes (86,6%) onde as famílias Sciaenidae (32%), Trichiuridae (26%) e Ariidae (16%) foram mais representativas e, quatro espécies de crustáceos (26%). A espécie não apresentou diferenças nos hábitos alimentares entre sexos, mas, os filhotes tiveram maior diversidade de presas que jovens e adultos. Finalmente, houve maior similaridade (0.89) entre a diversidade de presas de S. fluviatilis e as espécies de peixes quando o estuário apresenta características marinhas.

Fishing activity in Northern Rio de Janeiro State (Brazil) and its relation with small cetaceans

Research on fishing activity at Atafona village, in Northern Rio de Janeiro, Brazil (21°35'S), was carried out between 1987-96 for the purpose of relating it to the accidental capture of small cetaceans and of estimating the relationship between fishing activity and the diet of small cetaceans. Data on fishing operations were obtained at the cold storage plants management, from interviews with fishermen and personal observations. The most representative fishing resources were Xyphopenaeus kroyeri, Micropogonias furnieri, Carcharhinus plumbeus, C. acronotus,and Rhizoprionodon porosus. Gillnets are responsible for the accidental capture of small cetaceans in the region, mainly Pontoporia blainvillei and Sotalia fluviatilis (marine form). Four types of gillnets that are used on the region ("minjuada", "sarda", "caçoá" and "pescadinha") were dangerous to these species because they are placed in their preferred habitat. There is no competition between fishermen and small cetaceans due to the selection in the capture of commercialized fishes.

Investigação sobre a atividade pesqueira na localidade de Atafona, Norte do Rio de Janeiro, Brasil (21º25`S), foi conduzida entre 1987-96 com o objetivo de relacioná-la com a captura acidental e a dieta dos pequenos cetáceos. Dados sobre as operações pesqueiras foram obtidos na administração dos entrepostos de pesca, através de entrevistas com pescadores e observações pessoais. Os recursos pesqueiros mais representativos foram Xyphopenaeus kroyeri, Micropogonias furnieri, Carcharhinus plumbeus, C. acronotus, and Rhizoprionodon porosus. As redes de espera são responsáveis pela captura acidental de pequenos cetáceos na região, principalmente de Pontoporia blainvillei e Sotalia fluviatilis (forma marinha). Quatro tipos de redes de espera que são usadas na região ("minjuada", "sarda", "caçoá" and "pescadinha") foram mais perigosas para essas espécies pois são colocadas no seu hábitat preferencial. Não existe competição entre pescadores e pequenos cetáceos devido à seleção na captura dos peixes comercializados.