small cetaceans found stranded or accidentally captured in southeastern brazil: bioindicators of essential and non-essential trace elements in the environment.essential (cu, mn, se and zn) and non-essential (cd and hg) elements were analyzed in the hepatic tissue of 22 individuals of seven different species of small cetaceans (feresa attenuata; orcinus orca; pontoporia blainvillei; sotalia guianensis; stenella frontalis; steno bredanensis; tursiops truncatus) accidentally caught in fishing nets or found stranded along the northern coast of the state of rio de janeiro, brazil, between 2001 and 2010. atlantic spotted dolphin (s. frontalis) showed the hi ...201323993648
guiana dolphins (sotalia guianensis) and dr-calux for screening coastal brazilian environments for dioxins and related compounds.guiana dolphin is the top predator of highest toxicological concern in brazil and many studies on levels of persistent, bioaccumulative, and toxicant (pbt) pollutants have been performed on the species. however, due to high costs of the analyses, only one investigation comprised the determination of dioxins and related compounds (drcs) in guiana dolphin tissues. the dioxin responsive-chemically activated luciferase gene expression (dr-calux(®)) cell bioassay was used in the present study for the ...201627430575
whistle comparison of four delphinid species in southeastern brazil.the present study evaluates variations in frequency and duration parameters of whistles of four dolphin species (sotalia guianensis, steno bredanensis, stenella frontalis, and tursiops truncatus), recorded in the rio de janeiro state coast, southeastern brazil. a total of 487 whistles were analyzed. acoustic parameters of the whistles were classified to species by discriminant function analysis. overall classification score was 72.5%, with the highest classification score obtained for whistles o ...201627250196
guiana dolphins (sotalia guianensis, van benédén 1864) as indicators of the bioaccumulation of total mercury along the coast of rio de janeiro state, southeastern 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). concentr ...201222057227
high accumulation of perfluorooctane sulfonate (pfos) in marine tucuxi dolphins (sotalia guianensis) from the brazilian coast.perfluorooctane sulfonate (pfos) and other perfluoroalkyl compounds (pfcs) were measured in liver samples from 29 marine tucuxi dolphins from rio de janeiro state (rj), brazil. pfc measurement combined liquid chromatography and mass spectrometry, using a caplc system connected to a quadrupole-lit mass spectrometer. pfos was the only pfc detected and it was so in all samples. pfos concentrations (ng x g(-1) dw) of dolphins (n=23) from the highly contaminated guanabara bay (in rj) varied between 4 ...200818754395
an assessment of pcb and pbde contamination in two tropical dolphin species from the southeastern brazilian coast.pcbs and pbdes were determined in two dolphin species, sotalia guianensis and steno bredanensis, from an upwelling system off the central-northern coast of rio de janeiro, brazil. pcb levels varied from 0.040 to 0.75 μg g(-1) lw in muscles and from 0.022 to 1.32 μg g(-1)lw in liver samples from s. guianensis. in s. bredanensis, values varied from 0.085 to 11.3 μg g(-1) lw in muscles and from 0.024 to 18.6 μg g(-1) lw in livers. pcb-138, -153 and -180 were the major pcb congeners detected in both ...201526506024
high-frequency whistles of guiana dolphins (sotalia guianensis) in guanabara bay, southeastern brazil.guiana dolphins produce whistles with a higher frequency and less complexity than most other delphinid species. the present study used a recording system with sampling rate of 192 khz to describe the high-frequency whistles of sotalia guianensis in guanabara bay, rio de janeiro. eleven acoustic parameters (start, end, minimum, maximum, delta, center and peak frequency, duration, and frequency at 14, 12, and 34 of duration) were measured for all whistles. whistles with a fundamental frequency up ...201525618093
case report of flipper anatomic anomaly of sotalia guianensis from sepetiba bay, rio de janeiro.the cetacean flipper consists of a soft tissue that encases most of the forelimb containing humerus, radius, ulna, carpals, metacarpals, and phalanges. several studies have documented the typical cetacean's flipper anatomy, but only a few described digital anomalies and the most common are fusions and supernumerary such as polydactily and polyphalangy. the flippers of the guiana dolphin, sotalia guianensis have a falciform general aspect showing individual differences and marks produced by indiv ...201323630189
210polonium content of small cetaceans from southeastern brazil.the (210)po concentration of muscle and liver samples obtained from dolphins stranded on beaches in the southeastern region of rio de janeiro state was analyzed in the present study. the samples were primarily obtained from "franciscana" (pontoporia blainvillei) and "guiana" dolphins (sotalia guianensis); however, samples from four other species were also evaluated. the (210)po concentration of muscle samples obtained from "franciscana" dolphins (66.7±6.7, n=8)bq kg(-1)w.w. was greater than that ...201222304998
mercury, selenium and stable isotopes in four small cetaceans from the southeastern brazilian coast: influence of feeding strategy.dolphins are good bioindicators of the contamination status of marine ecosystems, since their dietary and habitat plasticity in both coastal and offshore ecotypes provide information on the trace elements levels originated from natural and anthropogenic sources. in this context, this study aimed to investigate provides mercury (hg), selenium (se) levels, trophic ecology and feeding environments of four small cetaceans (tursiops truncatus, steno bredanensis, sotalia guianensis and pontoporia blai ...201627593348
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