Heavy metal distribution in two cetacean species from Rio de Janeiro State, south-eastern Brazil

Author(s):  
Carlos Eduardo Veiga de Carvalho ◽  
Ana Paula M. Di Beneditto ◽  
Cristina Maria M. Souza ◽  
Renata M.A. Ramos ◽  
Carlos Eduardo Rezende

Mercury (Hg), cadmium (Cd) and zinc (Zn) concentration were analysed in muscular and liver tissues of two cetacean species, franciscana Pontoporia blainvillei and boto-cinza Sotalia guianensis, in order to compare their contamination levels in northern Rio de Janeiro State, south-eastern Brazil. The cutlassfish, Trichiurus lepturus, which is the preferential prey of the boto-cinza, have also been analysed. Liver tissue always presented higher concentrations when compared with muscle samples for all the studied metals. The boto-cinza showed higher concentrations for all metals in both tissues than in the franciscana, and the only exception was Cd. This result is probably related to the difference in size prey preference of each cetacean. Mercury was the only element that presented significant positive correlations with body length and age in both cetacean species. The cutlassfish showed rising Hg concentrations with weight and total length, suggesting a possible mercury pathway for marine mammals' contamination.

Author(s):  
Ana Paula Madeira Di Beneditto ◽  
Salvatore Siciliano

Along the central coast of Rio de Janeiro State (22°25′S–23°00′S), south-eastern Brazil, the marine tucuxi dolphin (Sotalia guianensis) feeds on neritic prey that are distributed through the water column and are abundant all year round. The most frequently found species were the teleost fish Trichiurus lepturus, Cynoscion guatucupa, Isopisthus parvipinnis and Porichthys porossisimus. Fish species were more important than cephalopod species in the diet of the marine tucuxi. Back calculations of prey sizes indicated that they feed mainly on young specimens. The present study provided additional information on the feeding habits of the marine tucuxi dolphin.


2012 ◽  
Vol 5 ◽  
Author(s):  
Liliane Lodi ◽  
Rodrigo Hipolito Tardin Oliveira ◽  
Luciana Duarte Figueiredo ◽  
Sheila Marino Simão

2013 ◽  
Vol 13 (3) ◽  
pp. 29-33 ◽  
Author(s):  
Ana Paula Madeira Di Beneditto ◽  
Carlos Eduardo Rezende ◽  
Plínio Barbosa Camargo ◽  
Helena Amaral Kehrig

The trophic niche of the sympatric predators Pontoporia blainvillei(franciscana dolphin) and Trichiurus lepturus (ribbonfish) was compared by stable isotope (δ15N and δ13C) ratios in hepatic and muscular tissues to understand how they co-exist in the northern Rio de Janeiro State (21°30′S-22°15′S), south-eastern Brazil. Dolphin specimens were incidentally captured through commercial gillnet fisheries, while fish specimens were the target of these fisheries. The predators had similar δ15N values in the liver (P. blainvillei: 14.6 ± 1.0‰; T. lepturus: 14.4 ± 0.6‰), which indicates similar trophic position in the recent food intake. However,P. blainvillei showed lighter δ15N values in muscle (13.8 ± 1.0‰) than T. lepturus (15.0 ± 0.4‰), revealing differences in the long term diet that could be related with the prey size ingested. The δ13C signatures showed a preferential inshore and benthic food chain for P. blainvillei (liver: −15.2 ± 0.6‰; muscle: −16.0 ± 0.5‰) and a more offshore and pelagic food chain for T. lepturus(liver: −17.2 ± 0.6‰; muscle: −16.8 ± 0.3‰). The isotopic variances of liver and muscle revealed a broader niche width to P. blainvillei in relation to T. lepturus, with a greater use of available food resources in coastal waters. In the area of study, the differences in habitat use and exploitation of food resources are favoring the predators' coexistence.


2009 ◽  
Vol 89 (6) ◽  
pp. 1243-1250 ◽  
Author(s):  
Konstantin R. Tabachnick ◽  
Larisa L. Menshenina ◽  
Daniela A. Lopes ◽  
Eduardo Hajdu

Descriptions of hexactinellid sponges collected by the RV ‘Marion Dufresne’ MD55 expedition on the Vitória–Trindade seamounts chain (off Espírito Santo State, south-eastern Brazil) in 1987 and stored in the MNHN (Muséum National d'Histoire Naturelle in Paris) are presented. Hyalonema (Cyliconema) conqueror sp. nov. (the first finding of this subgenus in the Atlantic Ocean) and H. (Prionema) dufresnei sp. nov. (the second record of this subgenus for the Atlantic Ocean) are described as new species. The holotype of H. (C.) conqueror sp. nov. was collected with a ROV at Campos Basin (off Rio de Janeiro State, south-eastern Brazil), while the paratypes originated from Vitória–Trindade seamounts chain and off Bahía State (eastern Brazil). Other hexactinellids reported here, Farrea sp., Sarostegia aff. oculata, Aphrocallistes aff. beatrix, Dactylocalyx aff. subglobosus and Euplectella suberea were known before to be widely distributed in the Atlantic Ocean. The total number of hexactinellid sponges known from Brazil has risen to 15 and from the south-western Atlantic to 23.


2018 ◽  
Vol 18 (3) ◽  
Author(s):  
Ana Paula Madeira Di Beneditto ◽  
Maria Thereza Manhães Tavares ◽  
Leandro Rabello Monteiro

Abstract: The isotopic niche of Bagre bagre and Genidens barbus target of commercial fisheries in a marine coastal area from northern Rio de Janeiro State (~21ºS), south-eastern Brazil was compared to evaluate the feeding assimilation and the trophic relationship. The mean isotopic values of the catfishes and their food items in the δ13C-δ15N space were coherent with their respective trophic positions. The relative contributions of the food items highlighted the shrimp Xiphopenaeus kroyeri as the most assimilated item in the diet of B. bagre, while for G. barbus the model highlighted the fish Porichthys porosissimus. The absence of niche overlap together with the trophic evenness point to a reduced feeding overlap between B. bagre and G. barbus in northern Rio de Janeiro State.


1993 ◽  
Vol 3 (1) ◽  
pp. 1-12 ◽  
Author(s):  
D. A. Scott ◽  
M. De L. Brooke

SummaryThe Grey-winged Cotinga Tijuca condita, previously known from a single specimen collected in 1942, was rediscovered near the type-locality in the coastal hill ranges of Rio de Janeiro state, south-eastern Brazil, in November 1980. Fieldwork at two sites in November/December 1980 and November 1981 revealed the presence of 10 individuals: one calling male and one female in cloud-forest at 1,320 m in the Serra do Tinguá; and six calling males, one female and one unsexed bird in cloud-forest at 1,830-2,000 m in the Serra dos Órgãos. Two females were netted, and two calling males were seen well in the field. The plumage of calling males resembled that of females, but was brighter with more grey on the face. The voice was described as an explosive sooee-wheee. The calling posture was similar to that of pihas Lipaugus, and there was no indication of any lekking behaviour. The species appears to have a very restricted distribution, but there is no indication that it is under threat at the present time.O cotingídeo Tijuca condita, previamente conhecido de um único indivíduo coletado em 1942, foi redescoberto próximo a sua localidade tipo nas montanhas da costa do estado do Rio de Janeiro, no sudeste do Brasil, em novembro de 1980. Observações no campo em duas localidades em novembro/dezembro 1980 e novembro 1981 revelaram a presença de 10 indivíduos: um macho cantando e uma fêmea em uma floresta de neblina a 1,320 m na Serra do Tinguá; seis machos, uma fêmea e um individuo de sexo não determinado em uma floresta de neblina a 1,830–2,000 m na Serra dos Órgãos. Duas fêmeas foram capturadas em rede e dois machos foram bem observados no campo. A plumagem dos machos assemelha-se a das fêmeas, contudo mais brilhante e acinzentado na face. O canto foi descrito como um explosivo sooee-wheee. A postura de canto foi semelhante à de outros cotingídeos Lipaugus e não há indícios de comportamento de leque. A espécie parece ter uma distribuição muito restrita, mas não ha indícios de que essa espécie esteja ameaçada no momento.


2015 ◽  
Vol 8 ◽  
Author(s):  
Ana Paula Madeira Di Beneditto ◽  
Jailson Fulgencio De Moura ◽  
Salvatore Siciliano

Studies of the feeding habits of sea turtles are important in identifying their feeding grounds and preferred prey, thus helping with management decisions regarding habitat protection. The present study describes, for the first time, the feeding habits of the sea turtlesCaretta carettaandLepidochelys olivaceain Rio de Janeiro State, south-eastern Brazil (22°06′S–22°55′S). The stomach contents of fiveC. carettaand fiveL. olivacearecovered between 2009 and 2010 were analysed to identify the prey species. A common feeding pattern was noted for both species, with bottom-dwelling prey (fish, crustaceans, molluscs and echinoderms), common in shallow environments, constituting the main food items. All fish and brachyuran crustacean species identified in the stomach contents were by-catch in small-scale shrimp fisheries that operate along the study area. The coastal waters of Rio de Janeiro State represent a new feeding ground forL. olivacea, expanding its preferential habitat during the non-reproductive period. The results provide strong evidence for the likelihood that sea turtles are interacting with fisheries due to an overlapping between feeding and fishery grounds. An evaluation of carcasses washed up on beaches is needed for a better understanding of the effects on the population dynamics of sea turtles.


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