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Danilewicz D.,Grupo de Estudos de Mamiferos Aquaticos do Rio Grande do Sul GEMARS | Moreno I.B.,Grupo de Estudos de Mamiferos Aquaticos do Rio Grande do Sul GEMARS | Ott P.H.,Grupo de Estudos de Mamiferos Aquaticos do Rio Grande do Sul GEMARS | Ott P.H.,State University of Rio Grande do Sul | And 5 more authors.
Journal of the Marine Biological Association of the United Kingdom | Year: 2010

The franciscana dolphin has been considered the most threatened small cetacean in the south-western Atlantic Ocean due to gillnet by-catch. The estimation of the species' abundance has been recommended as the highest research priority. A line transect aerial survey to estimate franciscana abundance in Rio Grande do Sul, southern Brazil, was carried out in February 2004. The overall surveyed area comprised 13,341 km2 and at least 20 transect lines. Abundance was estimated using distance sampling methods and assuming g(0) = 0.304. The corrected density is 0.51 franciscanas/km2, resulting in an abundance estimation of 6839 franciscanas (CV = 32%; 95% CI = 3709–12,594) for the surveyed area in Rio Grande do Sul. To improve this estimate: (a) perception bias should be determined; (b) the parameters influencing availability bias should be identified and quantified; and (c) survey sample size should be increased. While the lack of data to correct for perception bias and group size underestimation in this aerial survey is likely to yield an underestimate of franciscana abundance, the use of surfacing and diving time data from boat and land-based surveys to correct for availability bias is likely to cause its overestimation. Alternative values of the g0 group-size estimates and rates of increase were incorporated in the analyses, creating 240 different estimates of annual increment for this franciscana population. Even in the most optimistic scenario, the annual increment of franciscanas is not sustainable with the current levels of by-catch in Rio Grande do Sul, and fishery management to reduce by-catch must be initiated promptly. © 2010, Marine Biological Association of the United Kingdom. All rights reserved.

Van Bressem M.-F.,Cetacean Conservation Medicine Group CMED | Simoes-Lopes P.C.,Federal University of Santa Catarina | Felix F.,Museo de Ballenas | Kiszka J.J.,Florida International University | And 12 more authors.
Diseases of Aquatic Organisms | Year: 2015

We report on the epidemiology of lobomycosis-like disease (LLD), a cutaneous disorder evoking lobomycosis, in 658 common bottlenose dolphins Tursiops truncatus from South America and 94 Indo-Pacific bottlenose dolphins T. aduncus from southern Africa. Photographs and stranding records of 387 inshore residents, 60 inshore non-residents and 305 specimens of undetermined origin (inshore and offshore) were examined for the presence of LLD lesions from 2004 to 2015. Seventeen residents, 3 non-residents and 1 inshore dolphin of unknown residence status were positive. LLD lesions appeared as single or multiple, light grey to whitish nodules and plaques that may ulcerate and increase in size over time. Among resident dolphins, prevalence varied significantly among 4 communities, being low in Posorja (2.35%, n = 85), Ecuador, and high in Salinas, Ecuador (16.7%, n = 18), and Laguna, Brazil (14.3%, n = 42). LLD prevalence increased in 36 T. truncatus from Laguna from 5.6% in 2007-2009 to 13.9% in 2013-2014, albeit not significantly. The disease has persisted for years in dolphins from Mayotte, Laguna, Salinas, the Sanquianga National Park and Bahía Málaga (Colombia) but vanished from the Tramandaí Estuary and the Mampituba River (Brazil). The geographical range of LLD has expanded in Brazil, South Africa and Ecuador, in areas that have been regularly surveyed for 10 to 35 yr. Two of the 21 LLD-affected dolphins were found dead with extensive lesions in southern Brazil, and 2 others disappeared, and presumably died, in Ecuador. These observations stress the need for targeted epidemiological, histological and molecular studies of LLD in dolphins, especially in the Southern Hemisphere. © Inter-Research 2015.

Danilewicz D.,University Estadual Of Santa Cruz | Danilewicz D.,Instituto Aqualie | Ott P.H.,Grupo de Estudos de Mamiferos Aquaticos do Rio Grande do Sul GEMARS | Ott P.H.,State University of Rio Grande do Sul | And 7 more authors.
Marine Biodiversity Records | Year: 2013

The Atlantic spotted dolphin, Stenella frontalis, presents two geographically isolated populations in the western South Atlantic. This note reports on a 350 km northward extension range of the southern population. The sighted group of 80 animals was in waters 66 m deep and 75 nautical miles distant from the coast. The record was observed during a dedicated cetacean survey in Brazilian waters in the spring of 2008 and supports a discontinuous distribution along the coast of Brazil. © Marine Biological Association of the United Kingdom 2013.

Sacristan C.,University of Sao Paulo | Ressio R.A.,Instituto Adolfo Lutz | Castilho P.,Santa Catarina State University | De Azevedo Fernandes N.C.C.,Instituto Adolfo Lutz | And 13 more authors.
Diseases of Aquatic Organisms | Year: 2016

Cetacean lacaziosis-like disease or lobomycosis-like disease (LLD) is a chronic skin condition caused by a non-cultivable yeast of the order Onygenales, which also includes Lacazia loboi, as well as Paracoccidioides brasiliensis and P. lutzii, respectively responsible for lacaziosis and paracoccidioidomycosis in humans. Complete identification and phylogenetic classification of the LLD etiological agent still needs to be elucidated, but preliminary phylogenetic analyses have shown a closer relationship of the LLD agent to Paracoccidioides spp. than to L. loboi. Cases of LLD in South American cetaceans based on photographic identification have been reported; however, to date, only 3 histologically confirmed cases of LLD have been described. We evaluated multiple tissue samples from 4 Tursiops truncatus stranded in the states of Santa Catarina (n = 3) and Rio Grande do Sul (n = 1), southern Brazil. Macroscopically, all animals presented lesions consistent with LLD. Hematoxylin-eosin, periodic acid-Schiff, Grocott's methenamine silver, and Mayer's mucicarmin stains were used for histological evaluation. Microscopically, numerous refractile yeasts (4-9 μm in diameter) were observed in skin samples (4/4), and for the first time in dolphins, also in a skeletal muscle abscess (1/4). Immunohistochemistry using anti-P. brasiliensis glycoprotein gp43 as a primary antibody, which is known to cross-react with L. loboi and the LLD agent, was performed and results were positive in all 4 cases. We describe 3 new cases of LLD in cetaceans based on histopathology and immunohistochemistry. This is the first report of LLD in the muscle of cetaceans. © 2016 Inter-Research.

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