Helminths as biological tags for franciscana (Pontoporia blainvillei) (Cetacea, Pontoporiidae) in Argentinian and Uruguayan waters

Aznar, Francisco Javier; Raga, Juan Antonio; Corcuera, J. F.; Monzon, Federico Castro

doi:10.1515/mamm.1995.59.3.427

Cited by 40 publications

(27 citation statements)

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“…Regarding the former field of knowledge mentioned, diet was more similar among individuals inhabiting adjacent areas of Rio Grande do Sul and Uruguay (see Pinedo, 1982;Pinedo et al, 1989;Ott, 1994;Bassoi, 1997;Danilewicz et al, 2002) than between these two areas and Argentina (Rodríguez et al, 2002). With reference to parasites, Andrade et al (2000) stated that the distribution pattern of gastrointestinal helminths in franciscana was similar among individuals sampled in Rio Grande do Sul and Uruguay, while Aznar et al (1995) comparing the helminthofauna of franciscana between samples from Uruguay and Argentina observed differences in dominance and infection levels by the acanthocephalan worm Polymorphus cetaceum, the nematode Anisakis simplex, as well as by the trematode Hadwenius pontoporiae.…”

Section: Discussionmentioning

confidence: 99%

Cadmium concentrations in franciscana dolphin (Pontoporia blainvillei) from south brazilian coast

et al. 2007

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A B S T R A C TFranciscana dolphins were used as source of information on the bioavailability of cadmium in the neritic waters off South Brazilian Coast. Liver samples obtained from 44 individuals incidentally captured off Rio Grande do Sul State were analyzed by electrothermal AAS. Cadmium concentrations, age, total weight and length of the analyzed dolphins varied between 39 and 4144 µg.kg -1 (wet weight), one and five years, 17.5 and 49.2 kg, and between 105.3 and 156.8 cm, respectively. Concerning hepatic cadmium concentrations of franciscanas, there was no significant difference between data raised by the present study and information from literature, regarding Rio de Janeiro State. The low cadmium concentrations observed may be attributed to the fact that loliginid squids constitute the main cephalopod prey for franciscanas. This study corroborates investigations on cadmium levels in Brazilian squids and strengthened the hypothesis that cephalopods of Loliginidae Family do not constitute important vectors of the transfer of cadmium to cetaceans. R E S U M OFranciscanas foram utilizadas como fonte de informação sobre a biodisponibilidade de cádmio em águas neríticas da Costa Sul do Brasil. Amostras de fígado, obtidas de 44 indivíduos capturados acidentalmente ao largo da costa do Rio Grande do Sul, foram analisadas através de EAA eletrotérmica. Concentrações de cádmio, idade, peso e comprimento totais dos golfinhos analisados variaram entre 39 e 4144 µg.kg -1 (peso úmido), um e cinco anos, 17,5 e 49,2 kg, e entre 105,3 e 156,8 cm, respectivamente. Em relação às concentrações hepáticas de cádmio em franciscanas, não houve diferença significativa entre os dados gerados pelo presente estudo e informação proveniente da literatura, referente ao Estado do Rio de Janeiro. As baixas concentrações de cádmio observadas podem ser atribuídas ao fato de as lulas da Família Loliginidae constituírem a principal presa para franciscanas, dentre os cefalópodes. Este estudo corrobora investigações sobre níveis de cádmio em lulas brasileiras e reforça a hipótese de que cefalópodes loliginídeos não constituem vetores importantes da transferência de cádmio para cetáceos.

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Section: Discussionmentioning

confidence: 99%

Cadmium concentrations in franciscana dolphin (Pontoporia blainvillei) from south brazilian coast

et al. 2007

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“…Diet was found to be more similar between animals inhabiting areas in Rio Grande and Uruguay than between any of these areas and Argentina (Ott 1994;Pinedo 1982;Pinedo et al 1989). Aznar and colleagues (Aznar et al 1994(Aznar et al , 1995 and Andrade and colleagues (Andrade et al 2000) showed that parasite infection levels in franciscana dolphins from Rio Grande and Uruguay are significantly different to those sampled in Argentina.…”

Section: Isolation By Distance?mentioning

confidence: 99%

“…Four types of data are particularly relevant and could be used in combined analyses of population structure: (i) Oceanographic data may serve to construct a priori hypotheses regarding the placement of subpopulation boundaries for genetic analyses or to corroborate evidence of genetic structure, since environmental variables such as depth and temperature may have importance in the development of ecological niches (Hoelzel 1998;Natoli et al 2005). (ii) Ecological partitioning, derived from satellite telemetry data, parasite and contamination loads or feeding habits, may provide evidence of shallow population structure related to dispersal and movement patterns (Andrade et al 2000;Aznar et al 1994Aznar et al , 1995Bordino and Wells 2005;Ott 1994;Pinedo 1982;Pinedoet al 1989). (iii) Morphological characters served to propose and or define cetacean stocks and populations, and have been typically used before molecular techniques were commonly available (Messenger and McGuire 1998;Pinedo 1991;Rosenbaum et al 1995).…”

Section: Introductionmentioning

confidence: 99%

Conservation genetics of the franciscana dolphin in Northern Argentina: population structure, by-catch impacts, and management implications

2007

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Evaluating population structure in the marine environment is a challenging task when the species of interest is continuously distributed, and yet the use of population or stock structure is a crucial component of management and conservation strategies. The franciscana dolphin (Pontoporia blainvillei), a rare endangered coastal cetacean, suffers high levels of by-catch all along its distribution range in the Western South Atlantic, and questions have been raised about boundaries or divisions for population management. Here we apply genetic tools to better understand population structure and migration, sex-biased dispersal, and to assess potential genetic and demographic impacts of by-catch. Our analyses, based on mtDNA control region sequences, reveal significant genetic division at the regional level and fine-scale structure within our study area. These results suggest that the population in northern Buenos Aires is the most isolated population in Argentina. We found no significant departure from an equal sex ratio among the by-caught animals. A few cases of multiple entanglements appeared to be mother-calf pairs based on field observations and individuals sharing the same mtDNA control region lineage. The distribution of haplotype frequencies observed could imply that some maternal lineages are more prone to be subject to higher rates of by-catch, although biopsy sampling is necessary to fully evaluate whether maternal lineage distributions are the same for biopsy sampled and by-caught animals. A genetic indication of population size disequilibrium was detected for all populations in Argentina, which is consistent with available rates of by-catch and abundance estimates. Collectively, our findings support the current scheme of larger recognized Franciscana Management Areas (FMA), but argue for a finer-scale subdivision within Northern Buenos Aires region (FMA IV). Finally, an integrated approach to promote conservation of this endangered small cetacean has to involve identification of genetic and demographic threats, a more sustainable fishery strategy to reduce by-catch, and designation of protected areas that are supported by underlying population structure for franciscana dolphins.

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“…Comparisons of infection levels of one or more species of parasites among host groups within a given geographic area can aid in the identification of populations that are segregated, potentially comprising different ecological stocks (e.g. Szidat, 1964;MacKenzie, 1987;Dailey and Vogelbein, 1991;Moser, 1991;Aznar et al, 1995;Balbuena et al, 1995;Aznar et al, 1997a, Walker, 2001). The use of such information as a tool to examine the stock structure of the franciscana has already been recommended (Reeves and Leatherwood, 1994;IBAMA, 1997).…”

Section: Introductionmentioning

confidence: 99%

Parasites of franciscana (<i>Pontoporia blainvillei</i>) from São Paulo and Paraná States, Brazil

Marigo¹,

Rosas²,

Andrade³

et al. 2002

Lat. Am. J. Aquat. Mamm.

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The franciscana, Pontoporia blainvillei, is a threatened small cetacean of the western South Atlantic Ocean and is commonly caught incidentally in fishing nets along its distribution. Detailed studies regarding parasite loads of P. blainvillei have been recommended as a tool to evaluated ecological segregation and stock structure. We analyzed metazoan parasites from stomach, intestines and lungs of 41 franciscanas from three close geographical areas: Group 1, Guarujá ). The sample consists mainly of immature specimens, less than 3 years old. No parasites were found in the lungs analyzed. The acanthocephalan (Polymorphus sp) found in two stomachs were considered occasional. The trematode Hadwenius pontoporiae (Digenea: Campulidae) was the only parasite found in the intestines with prevalence of 100% for Group 1, 82.35% for Group 2 and 58.33% for Group 3. The mean intensity of H. pontoporiae for Groups 1, 2 and 3 was 39.5, 25.05 and 13.5 parasites per host, respectively. In this study there was a significant difference between the number of parasites among the three groups (Kruskal-Wallis test, p=0.012). Groups 2 and 3 are geographically close, and exhibited non-significant differences in the total number of parasites found (Mann-Whitney test, p=0.063). Groups 1 and 3, that are further apart geographically, differed significantly in the total number of parasites found (Mann-Whitney test, p=0.003). Through the analysis of data from the areas where H. pontoporiae was found [i.e. Areas 1, 2, 3 (this study), Rio Grande do Sul State and Argentina], it could be noticed that the prevalence and mean intensity increase as latitude increases. H. pontoporiae may continue to be useful as a biological tag for identifying franciscanas ecological stocks, together with information from genetic, morphometric and other biological studies. However, it is essential that standardized methodology be used in the collection of the parasite data.Resumo A toninha, Pontoporia blainvillei, é um cetáceo ameaçado do Atlântico Sul Ocidental. Captura acidentais ao longo de sua distribuição são freqüentes. O uso de informações a respeito dos parasitas de P. blainvillei é recomendado para avaliar segregações ecológicas e diferenciar estoques populacionais. Estômagos, pulmões e intestinos de 41 animais foram analisados buscando parasitos metazoários. Os animais são provenientes de 3 áreas geográficas próximas: Grupo 1, Guarujá e Praia Grande ( ). A amostra consiste basicamente de animais imaturos, entre 0 e 3 anos de idade. Nenhum parasito foi encontrado nos pulmões analisados. O acantocéfalo Polymorphus sp, encontrado em dois estômagos foi considerado ocasional. O trematóide Hadwenius pontoporiae (Digenea: Campulidae) foi o único parasito encontrado nos intestinos com prevalência de 100% para o Grupo 1, 82,35% para o Grupo 2 e 58,33% para o Grupo 3. A intensidade média de H. pontoporiae nos Grupos 1, 2 e 3 foi de 39,5; 25,05 e 13,5 parasitos por hospedeiro, respectivamente. Houve uma diferença significativa entre o número de parasitas dos...

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Helminths as biological tags for franciscana (Pontoporia blainvillei) (Cetacea, Pontoporiidae) in Argentinian and Uruguayan waters

Cited by 40 publications

References 0 publications

Cadmium concentrations in franciscana dolphin (Pontoporia blainvillei) from south brazilian coast

Cadmium concentrations in franciscana dolphin (Pontoporia blainvillei) from south brazilian coast

Conservation genetics of the franciscana dolphin in Northern Argentina: population structure, by-catch impacts, and management implications

Parasites of franciscana (<i>Pontoporia blainvillei</i>) from São Paulo and Paraná States, Brazil

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