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Rio de Janeiro, Brazil

De Moura J.F.,PPG em Saude Publica e Meio Ambiente | Di Dario B.P.S.,Grupo de Estudos de Mamiferos Marinhos da Regiao Dos Lagos GEMM Lagos | Siciliano S.,Grupo de Estudos de Mamiferos Marinhos da Regiao Dos Lagos GEMM Lagos
Marine Biodiversity Records | Year: 2011

The present knowledge of pinnipeds' distribution is principally based on the location of breeding colonies. Several species of pinnipeds have shown the ability to undertake long travels to different and unusual locations, where they are frequently interpreted as vagrants. A total of seven species of pinnipeds are known to occur along the Brazilian coast: four belong to the family Otariidae and three to the family Phocidae. From 1954 to 2008 a total of 54 records of pinnipeds were reviewed for the coast of Rio de Janeiro State, ten of them were new records, representing 18.2% of the total. The most common species registered in the study area was Arctocephalus tropicalis (49.1%; N=27) followed by Mirounga leonina (20%; N=11). The other species recorded were Lobodon carcinophaga, Otaria flavescens, Arctocephalus australis and Hydrurga leptonyx. From 51 pinniped specimens with information on periods of occurrence, 76.5% (N=39) were reported during winter, and the other 12 specimens were equally distributed over the three other seasons. Most sub-Antarctic fur seals (88%) and southern elephant seals (83%) were males. The majority of the species were classified as sexually immature. The seasonal pattern of the pinnipeds found on the coast of Rio de Janeiro State is related to the intensive northward flow of the Malvinas/Falkland Current during winter. In addition, the potential to swim long distances together with the lack of physical barriers in the marine environment could help the dispersion of the seals to distant regions far from their traditional breeding or feeding regions. © 2011 Marine Biological Association of the United Kingdom. Source


De Moura J.F.,PPG em Saude Publica e Meio Ambiente | Hacon S.D.S.,Escola Nacional de Saude Publica ENSP FIOCRUZ | Vega C.M.,Pontifical Catholic University of Rio de Janeiro | Hauser-Davis R.A.,Pontifical Catholic University of Rio de Janeiro | And 2 more authors.
Bulletin of Environmental Contamination and Toxicology | Year: 2012

Total mercury (Hg) was determined in muscle tissue of 20 Guiana dolphins stranded along the coast of Rio de Janeiro state, Brazil, with a mean of 1.07 μg/g wet weight. Mercury concentrations were positively related to body length, possibly related to the capacity of the dolphins to bioaccumulate this element throughout life. The Hg concentrations were not significantly different between males and females, although females (1.08 μg/g) showed slightly higher levels than males (1.04 μg/g). Concentrations were low when compared to results of studies carried out with small cetaceans in the Northern Hemisphere, and with previous studies in the Southeastern Brazil. © 2011 Springer Science+Business Media, LLC. Source


de Moura J.F.,PPG em Saude Publica e Meio Ambiente
Reviews of environmental contamination and toxicology | Year: 2014

Guiana dolphins (Sotalia guianensis) are small cetaceans that inhabit coastal regions down to a 50 m depth. As a coastally distributed species, they are exposed to a variety of human-induced risks that include passive fishing nets, persistent environmental pollution, and emerging diseases. As a top predatorS. guianensis occupies an important ecological niche in marine ecosystems. However, this niche also exposes this dolphin to extensive biomagnification of marine contaminants that may accumulate and be stored throughout their life of about 30 years.In this paper, we have compiled available data on the Guiana dolphin as regards its exposure to chemical pollutants, pathogenic microbes, infectious diseases, and injuries caused by interactions with passive fishing gears. Our analysis of the data shows that Guiana dolphins are particularly sensitive to environmental changes.Although the major mortal threat to dolphins results from contact with fishing other human-related activities in coastal zones also pose risks and need more attention.Such human-related risks include the presence of persistent toxicants in the marine environment, such as PCBs and PBDEs. Residues of these chemicals have been detected in Guiana dolphin's tissues at similar or higher levels that exist in cetaceans from other known polluted areas. Another risk encountered by this species is the non lethal injuries caused by fishing gear. Several incidents of this sort have occurred along the Brazilian coast with this species. When injuries are produced by interaction with fishing gear, the dorsal fin is the part of the dolphin anatomy that is more affected, commonly causing severe laceration or even total loss.The Guiana dolphins also face risks from infectious diseases. The major ones thus far identified include giardiasis, lobomycosis, toxoplasmosis, skin and skeletal lesions. Many bacterial pathogens from the family Aeromonadaceae and Vibrionaceae have been isolated from Guiana dolphins. Several helminth species have also been observed to affectS. guianensis. These results suggest a vulnerability of this species to environmental disturbances. Moreover, there is some evidence that the effects of some infectious diseases may be enhanced from stress caused by habitat impairment. For example, certain diseases and pathogenic organisms in S.guianensis may be associated with the high levels of endocrine-disruptor contaminants(e.g., PCBs; DDTs; PBDEs) that have been detected in marine waters.Although the data available on S. guianensis is growing, most of the work has been focused on a small portion of the species total area of distribution. Most studies,to date, have been carried out in the Southern region of the distribution, and in north eastern Brazil. Few studies have been conducted in the northern region of the South America or in Central America. Therefore, future studies should be conducted that address the heterogeneity of this species total distribution.The biology and ecology of the Guiana dolphin renders this species potentially useful as a sentinel species for detecting environmental changes, such as chemical and biological pollution. Research about this dolphin is encouraged as a way to assess what coastal environmental changes have occurred and to continue evaluating the health status of this vulnerable species in a changing environment. Source


De Moura J.F.,PPG em Saude Publica e Meio Ambiente | Emin-Lima R.,PPG em Saude Publica e Meio Ambiente | Hacon S.S.,Grupo de Estudos de Mamiferos Marinhos da Regiao Dos Lagos | Vega C.M.,Pontifical Catholic University of Rio de Janeiro | And 2 more authors.
Bulletin of Environmental Contamination and Toxicology | Year: 2012

Total mercury (Hg) was analyzed in muscle tissue of 27 accidentally captured Guiana dolphins (Sotalia guianensis) in order to evaluate Hg contamination levels present in the Amazon Continental Shelf, in Amapá state, North Brazil. The samples showed a mean concentration of 0.4 ± 0.16 μg/g wet weight (ww), ranging from 0.07 to 0.79 μg/g ww. As observed in several other cetacean species, Hg concentrations presented positive correlations to body length, related to the capacity to bioaccumulate this element throughout life. Hg concentrations were not significantly different between males (mean = 0.38 μg/g ww; n = 15) and females (mean = 0.42 μg/g ww; n = 12). Concentrations were low when compared to results of studies carried out with small cetaceans in the Northern Hemisphere, and with some previous studies in the southeastern region of Brazil. In contrast with high Hg concentrations normally detected in river dolphin samples from Amazon River tributaries, our results suggest that the Amazon coast contains low levels of Hg in bioavailable form. © Springer Science+Business Media, LLC 2012. Source

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