Brominated flame retardants and natural organobrominated compounds in a vulnerable delphinid species along the Brazilian coast.

Guiana dolphins, Sotalia guianensis, are vulnerable to extinction along their distribution on the Brazilian coast and assessing chemical pollution is of utmost importance for their conservation. For this study, 51 carcasses of Guiana dolphins were sampled across the Brazilian coast to investigate legacy and emerging brominated flame retardants (BFRs) as well as the naturally-produced MeO-BDEs. PBDEs and MeO-BDEs were detected in all samples analyzed, whereas emerging BFRs were detected in 16 % of the samples, all in Rio de Janeiro state. PBDE concentrations varied between 2.24 and 799 ng.g-1 lipid weight (lw), emerging BFRs between 0.12 and 1.51 ng.g-1 lw and MeO-BDEs between 3.82 and 10,247 ng.g-1 lw. Concentrations of legacy and emerging BFRs and natural compounds varied considerably according to the sampling site and reflected both the local anthropogenic impact of the region and the diversity/mass of biosynthesizers. The PBDE concentrations are lower than what was found for delphinids in the Northern Hemisphere around the same sampling period and most sampling sites presented mean concentrations lower than the limits for endocrine disruption known to date for marine mammals of 460 ng.g-1 lw, except for sampled from Santa Catarina state, in Southern Brazil. Conversely, MeO-BDE concentrations are higher than those of the Northern Hemisphere, particularly close to the Abrolhos Bans and Royal Charlotte formation, that are hotspots for biodiversity. Despite the elevated concentrations reported for this group, there is not much information regarding the effects of such elevated concentrations for these marine mammals. The distinct patterns observed along the Brazilian coast show that organobrominated compounds can be used to identify the ecological segregation of delphinids and that conservation actions should be planned considering the local threats.

Feeding ecology based on stable carbon and nitrogen isotopes: A comparative study on different Guiana dolphin tissues.

Different tissues are used for stable isotope analysis in cetacean investigations. However, variation in the isotopic composition of tissues with different turnover rates has been reported for cetaceans. To better understand stable carbon and nitrogen isotopes (δ13C and δ15N) in skin compared to other tissues, this study assessed the isotopic variation among the liver, muscle, and skin of Guiana dolphins (Sotalia guianensis), as well as the influence of sex on these variations. No differences were found in δ13C among male tissues, but females showed lower values in the liver compared to muscle and skin. Differences in δ15N were observed among all tissues, with different variation patterns for males and females. Four females were distinguished from males and other females by their 13C depletion in all tissues and δ15N variation pattern. We conclude that skin and muscle may be equivalent in δ13C values for Guiana dolphins. The multiple-tissue analysis brings new insights into their feeding ecology and provides background for stable isotope analysis using non-destructive sampling techniques in small cetaceans.

Cetaceans along the southeastern Brazilian coast: occurrence, distribution and niche inference at local scale.

It is deemed important to understand cetacean occurrence and distribution to comprehend their ecological roles. The geographical occurrence of species' niche can be used to better describe their potential distribution. The niche can be defined using environmental variables. Those variables are considered static and not affected by biological activities. The present study goal was to assess the occurrence and distribution of cetaceans along the southeastern Brazilian coast, as well as to define the fundamental and realized niche of each species and to investigate niche overlap at local scale. The environmental requirements for each species were also investigated throughout statistical tests. Sighting data were obtained through oceanographic surveys conducted between 2012 and 2015. The environmental variables available on MARSPEC and the software NicheA were used for the ecological niche modeling. A total of twelve cetacean species were identified and the potential distribution areas of the six commonest ones were defined. Even though the species presented different environmental preferences, most of them had partial overlap among niches and potential distribution areas. The environmental heterogeneity of the study area might support the co-occurrence of different species with different environmental requirements.

The Pathology of Cetacean Morbillivirus Infection and Comorbidities in Guiana Dolphins During an Unusual Mortality Event (Brazil, 2017-2018).

Cetacean morbillivirus (CeMV; Paramyxoviridae) is the most significant pathogen of cetaceans worldwide. The novel "multi-host" Guiana dolphin (Sotalia guianensis; GD)-CeMV strain is reported in South American waters and infects Guiana dolphins and southern right whales (Eubalaena australis). This study aimed to describe the pathologic findings, GD-CeMV viral antigen distribution and detection by RT-PCR (reverse transcriptase polymerase chain reaction), and infectious comorbidities in 29 Guiana dolphins that succumbed during an unusual mass-mortality event in Rio de Janeiro state, Brazil, between November 2017 and March 2018. The main gross findings were lack of ingesta, pulmonary edema, ascites, icterus, hepatic lipidosis, multicentric lymphadenomegaly, as well as pneumonia, polyserositis, and multiorgan vasculitis caused by Halocercus brasiliensis. Microscopically, the primary lesions were bronchointerstitial pneumonia and multicentric lymphoid depletion. The severity and extent of the lesions paralleled the distribution and intensity of morbilliviral antigen. For the first time in cetaceans, morbilliviral antigen was detected in salivary gland, optic nerve, heart, diaphragm, parietal and visceral epithelium of glomeruli, vulva, and thyroid gland. Viral antigen within circulating leukocytes suggested this as a mechanism of dissemination within the host. Comorbidities included disseminated toxoplasmosis, mycosis, ciliated protozoosis, and bacterial disease including brucellosis. These results provide strong evidence for GD-CeMV as the main cause of this unusual mass-mortality event.

The lungworm, Halocercus brasiliensis (Nematoda: Pseudaliidae), from Guiana Dolphins Sotalia guianensis from Brazil with Pathological Findings.

The Guiana dolphin, Sotalia guianensis, is a small cetacean species found on the Atlantic coast of Central and South America from Honduras to Santa Catarina State, Brazil. The nematode Halocercus brasiliensis infects this cetacean, resulting in lung pathologies and death. The present study aimed to conduct a morphological and morphometric study of specimens of H. brasiliensis collected from S. guianensis from the coast of the state of Espírito Santo, Brazil. For this study, 7 dolphins were collected and examined for the presence of lung parasites. Nematodes were collected and processed for light microscopy, and lung fragments were processed for histological analysis. The nematodes were identified as H. brasiliensis according to their morphology and morphometry. The histopathological analysis revealed mineralization of the bronchiolar cartilage and inflammatory process. The parasitic infections by H. brasiliensis in S. guianensis can contribute to the debilitating status of these cetaceans, resulting in their stranding and accidental capture in fishing nets.

Cetacean movements in coastal waters of the southwestern Atlantic ocean / Movimentos de cetáceos pelas águas costeiras do sudoeste do oceano Atlântico

Abstract: Cetaceans were monitored along ca. 700 km of the southeast coast of Brazil (22°S to 25°S) from 1995 to 2014 using photo-identification. The objective of this study was to identify any presence of long-distance movements for monitored cetacean species and discuss implications. Data on long-range movements of four of the monitored species are presented after the analysis of 321,765 photographs taken for individual identification. Seven individuals from four populations of Guiana dolphins (Sotalia guianensis) considered resident to particular estuaries or bays were reported in dispersal involving movement between pairs of protected areas over long-range distances varying between 86 and 135 km. Three cataloged rough-toothed dolphins (Steno bredanensis), first seen in Guanabara Bay, Rio de Janeiro state (22°46'S) in November 2011, were sighted 240 km southwards as members of the same group in coastal waters of São Paulo state (23°46'S) in July 2014. Water depth for those sightings ranged from 16 to 52.7 m; local sightings of rough-toothed dolphins in Brazil have frequently been in shallow waters, but the species global distribution is usually associated with deeper waters. In a 27-day interval in the spring of 2012, a group of 16 orcas (Orcinus orca) travelled ca. 277 km in shallow coastal waters ranging from 20 to 30 m deep. Orcas are commonly observed between November and February in southeast Brazil, probably in search for prey. In summer months between 2012 and 2014, three Bryde's whales (Balaenoptera edeni) sighted in waters ranging from 14 to 49 m deep, moved between 218 and 327 km. Bryde's whales are usually found in local coastal waters where they spend summer months feeding on sardines. To date, these are the longest estimated movements reported to S. guianensis, S. bredanensis, O. orca and B. edeni in the Southwestern Atlantic Ocean.

Resumo: Cetáceos foram monitorados em cerca de 700 km da costa sudeste do Brasil (22°S a 25°S) entre 1995 e 2014 com o uso da fotoidentificação. O objetivo deste estudo foi de identificar quaisquer presenças de movimentos de longa distância de indivíduos das espécies monitoradas e discutir suas implicações. Dados de movimentos de longa distância de quatro das espécies monitoradas são apresentados após a análise de 321.765 fotos obtidas para identificações individuais. Sete indivíduos de quatro populações de boto-cinza (Sotalia guianensis) consideradas residentes a estuários e baías particulares foram reportados em movimentos de dispersão envolvendo pares de áreas protegidas em distâncias que variaram entre 86 e 135 km. Três golfinhos-de-dentes-rugosos (Steno bredanensis) catalogados e avistados primeiramente na Baía de Guanabara, Rio de Janeiro (22°46'S), em novembro de 2011, foram avistados 240 km mais ao sul como membros de um mesmo grupo nas águas costeiras do Estado de São Paulo (23°46'S) em julho de 2014. A profundidade da água onde essas avistagens aconteceram variou entre 16 e 52,7 m; avistagens de golfinhos-de-dentes-rugosos têm sido efetuadas em águas rasas na costa sudeste do Brasil, embora a distribuição global da espécie esteja associada a águas profundas. Em um intervalo de 27 dias na primavera de 2012, um grupo de 16 orcas (Orcinus orca) se desclocou cerca de 277 km em águas rasas variando entre 20 e 30 m. Orcas são comumente avistadas entre novembro e fevereiro no sudeste do Brasil, possivelmente em busca de presas. Nos meses de verão entre 2012 e 2014, três baleias-de-Bryde (Balaenoptera edeni) avistadas em águas de 14 a 49 m de profundidade, moveram-se entre 218 e 327 km. baleias-de-Bryde são encontradas em águas costeiras locais onde passam os meses de verão se alimentando de sardinhas. Até o presente momento, esses são os deslocamentos estimados como os de maiores distâncias observados para S. guianensis, S. bredanensis, O. orca and B. edeni no Atlântico Sudoeste.

Molecular identification and microscopic characterization of poxvirus in a Guiana dolphin and a common bottlenose dolphin, Brazil.

The poxviruses identified in cetaceans are associated with characteristic tattoo or ring skin lesions. However, little is known regarding the prevalence and progression of these lesions and the molecular characterization of cetacean poxviruses in the Southern Hemisphere. This manuscript describes the progression of poxvirus-like skin lesions in 5 free-ranging Guiana dolphins Sotalia guianensis. Additionally, 151 skin samples from 113 free-ranging cetaceans from Brazil, including 4 animals with tattoo skin lesions, were selected for poxvirus testing. Poxviral DNA polymerase gene PCR amplification was used to detect the virus in ß-actin-positive samples (145/151). DNA topoisomerase I gene PCR was then used in Cetaceanpoxvirus (CePV)-positive cases (n = 2), which were further evaluated by histopathology and electron microscopy. Based on photo-identification, adult Guiana dolphins presented regressing or healed poxvirus-like lesions (2/2), while juveniles presented persistent (2/3) or healed and progressive lesions (1/3). CePV DNA was amplified in a common bottlenose dolphin Tursiops truncatus and in a Guiana dolphin. Intracytoplasmic inclusion bodies and viral particles consistent with poxvirus were identified by histology and electron microscopy, respectively. CePV-specific amino acid motifs were identified through phylogenetic analysis. Our findings corroborate previous studies that suggest the placement of poxviruses from cetaceans within the novel CePV genus. This is the first molecular identification of poxvirus in South American odontocetes.

Guiana Dolphin Unusual Mortality Event and Link to Cetacean Morbillivirus, Brazil.

During November-December 2017, a mass die-off of Guiana dolphins (Sotalia guianensis) began in Rio de Janeiro, Brazil. Molecular and pathologic investigations on 20 animals indicated that cetacean morbillivirus played a major role. Our findings increase the knowledge on health and disease aspects of this endangered species.

Marine debris ingestion by coastal dolphins: what drives differences between sympatric species?

This study compared marine debris ingestion of the coastal dolphins Pontoporia blainvillei and Sotalia guianensis in a sympatric area in Atlantic Ocean. Among the 89 stomach contents samples of P. blainvillei, 14 (15.7%) contained marine debris. For S. guianensis, 77 stomach contents samples were analyzed and only one of which (1.30%) contained marine debris. The debris recovered was plastic material: nylon yarns and flexible plastics. Differences in feeding habits between the coastal dolphins were found to drive their differences regarding marine debris ingestion. The feeding activity of P. blainvillei is mainly near the sea bottom, which increases its chances of ingesting debris deposited on the seabed. In contrast, S. guianensis has a near-surface feeding habit. In the study area, the seabed is the main zone of accumulation of debris, and species with some degree of association with the sea bottom may be local bioindicators of marine debris pollution.

Use of carbon and nitrogen stable isotopes to study the feeding ecology of small coastal cetacean populations in southern Brazil

Samples from individuals of the populations of Sotalia guianensis (Guiana) and Pontoporia blainvillei (Franciscana) dolphins living in the Babitonga Bay estuary (26° 28′ S/48° 50′ W), and samples from individuals of a second population of P. blainvillei from a nearshore area (26° 38′ S/48° 41′ W), were collected and analyzed along with their prey between 2000 and 2006, to determine the carbon and nitrogen stable isotope ratios and to verify differences in their feeding ecology. No differences were found in the median ð15N values of Guiana (15.2‰) and Franciscana (15.9‰) dolphins living in Babitonga Bay, nor of nearshore Franciscana (15.0‰) individuals, suggesting no variation in the trophic level of these populations. However, the lack of more information on the isotopic compositions of their putative prey in the nearshore areas prevents the ability to draw definitive conclusions on this issue. The estuarine Franciscana and Guiana dolphin populations presented mean ð13C values of approximately −15.7‰, which were not statistically different from nearshore Franciscana individuals (−14.8‰). Based on stomach content analyses of these species from a previous study, it was reported that there was little overlap in the diet of estuarine Franciscanas and Guiana dolphins. However, based on the similarity of the ð13C values between these two species and of their putative prey, it appears that in fact there is an overlap in the diet of these two species. Based solely on stable isotope analysis, it was not possible to differentiate between estuarine and nearshore Franciscana populations, making it difficult to conclude whether captured nearshore specimens were indeed yearlong residents of these areas. Finally, this study suggests that Franciscana and Guiana dolphin populations are sharing the same resources, mostly L. brevis, D. rhombeus, and S. rastrifer. Therefore, the combination of resource sharing and commercial exploitation of their prey makes these two cetacean species vulnerable.

Amostras de tecido de indivíduos pertencentes às populações de Sotalia guianensis (boto-cinza) e Pontoporia blainvillei (toninha) que vivem no estuário da Baía da Babitonga (26° 28′ S/48° 50′ W) e de uma segunda população de P. blainvillei da área costeira (26° 38′ S/48° 41′ W) foram coletadas entre os anos 2000 e 2006 para determinar as composições de isótopos estáveis de carbono e nitrogênio, assim como de suas presas para analisar diferenças na ecologia alimentar. Não foram detectadas diferenças nos valores médios de ð15N entre os botos-cinza (15.2‰) e as toninhas (15.9‰) que vivem na Baía da Babitonga, e entre indivíduos de toninhas da área costeira (15.0‰), sugerindo que não existe variação no nível trófico destas populações. Contudo, a ausência de informações mais completas sobre a composição isotópica das presas na área costeira limita a proposição de conclusões mais definitivas sobre esta temática. As populações estuarinas de toninhas e botos-cinza apresentaram valores médios de ð13C de aproximadamente −15.7‰, que não apresentaram diferença estatística com relação às toninhas da área costeira (−14.8‰). Baseado na análise de conteúdos estomacais destas espécies num estudo anterior sugere-se que não há sobreposição na dieta das toninhas e botos-cinza do estuário. Contudo, baseado na similaridade dos valores de ð13C entre estas espécies e nos distintos valores de ð13C de suas presas, há indícios de que de fato existe uma sobreposição na dieta destas duas populações. Com base apenas na análise de isótopos estáveis não foi possível diferenciar a população estuarina e costeira de toninhas, tornando-se difícil concluir se os indivíduos capturados acidentalmente na área costeira eram residentes de longo prazo. Finalmente, este estudo sugere que toninhas e botos-cinza estão compartilhando os mesmos recursos, principalmente L. brevis, D. rhombeus e S. rastrifer. Portanto, a exploração comercial dessas espécies pode ameaçar a sobrevivência do boto-cinza e das toninhas na Baía da Babitonga.

Crescimento e desenvolvimento de boto-cinza (Sotalia guianensis) do litoral do Espírito Santo / Growth and development of estuarine dolphin (Sotalia guianensis) from Espírito Santo coast

Estudou-se o desenvolvimento do boto-cinza (Sotalia guianensis) do litoral do Espírito Santo e verificou-se se a análise das radiografias da aleta peitoral pode ser utilizada para tal. Trinta e sete botos passaram pela determinação do comprimento total (CT), análise do grau de fusionamento das vértebras e radiografia das aletas peitorais. O CT ao nascimento foi de 103,3cm e o de animais maduros fisicamente 187,5cm. Observou-se correlação entre o CT, as epífises distais do rádio e da ulna e correlação entre o grau de fusionamento vertebral e a epífise distal do rádio. Concluiu-se que a análise radiográfica das aletas peitorais é uma boa maneira de avaliar o grau de maturação física do boto.

The aim of this study is to analyze the development of the estuarine dolphin from the coast of Espírito Santo and verify that the analysis of X-rays of pectoral fin can be used for such. Thirty-seven Sotalia guianensis were used, determining the TL, examination of the degree of fusion of the vertebrae and X-ray of pectoral fins. At birth the TL is 103.3cm and in physically mature animals the TL is 187.5cm. The TL showed a significant correlation with the epiphyses of the distal radius and ulna and the degree of spinal fusion showed significant correlation with distal radius. It can be concluded that the X-ray analysis of the pectoral fins is a good way of assessing the physical maturation of these animals and can be used in routine procedures.

Feeding associations between Guiana dolphins, Sotalia guianensis (Van Bénèden, 1864) and seabirds in the Lagamar estuary, Brazil / Associações de alimentação entre o boto-cinza (Sotalia guianensis) (Van Bénèden, 1864) e aves marinhas no estuário do Lagamar, Brasil

The main objective of the present study was to describe the characteristics regarding interactions between Guiana dolphins, Sotalia guianensis and seabirds in feeding associations in two distinct areas of the Lagamar estuary, Brazil. Boat-based surveys directed towards photo-identification studies of S. guianensis were conducted in the Cananéia Estuary (CE) (25° 01' S and 47° 55' W) from July 2004 to March 2008, as well as in the Paranaguá Estuarine Complex (PEC) (25° 24' S and 48° 24' W) from April 2006 to February 2008. On all occasions when seabirds were observed engaging in multi-species feeding associations with S. guianensis, data on species involved and their numbers were gathered. From 435 observed groups of S. guianensis in the CE, 38 (8.7 percent) involved interactions with seabirds. In the PEC, from the 286 observed groups, 32 (11.2 percent) involved the mentioned interactions. The following seabirds were observed in feeding associations with S. guianensis: Fregata magnificens, Sula leucogaster, Phalacrocorax brasilianus, and Sterna sp. In the CE, S. leucogaster was more commonly observed in feeding associations with Guiana dolphins (χ2 = 22.84; d.f. = 3, p < 0.05), while in the PEC no differences were reported when comparing seabird species (χ2 = 5.78; d.f.=3, p = 0.1223). In the CE, feeding associations were significantly more frequent in inner waters (subset A0; χ2 = 9.52; d.f. = 2, p < 0.05), and in winter (χ2 = 12.46; d.f. = 1, p < 0.05). Within these events, 44.7 percent of the association groups were composed by more than one seabird species. Seasonality in feeding associations was also observed in the PEC (χ2 = 4.76; d.f. = 1, p < 0.05), with same patterns observed in the CE. Interactions were more frequent in inner waters of the Laranjeiras bay, PEC (χ2 = 11.65; d.f. = 2, p < 0.05). Within these events, 74.2 percent of the association groups were composed by more than one seabird species. ...

O objetivo principal do presente estudo foi de descrever as características a respeito das associações de alimentação entre o boto-cinza, Sotalia guianensis, e aves marinhas em duas áreas distintas do estuário do Lagamar, Brasil. Investigações efetuadas a partir de embarcação e direcionadas a estudos de foto-identificação de S. guianensis foram conduzidas no Estuário de Cananéia (EC) (25° 01' S e 47° 55' O) entre julho de 2004 e março de 2008, bem como no Complexo Estuarino de Paranaguá (CEP) (25° 24' S e 48° 24' O) entre abril de 2006 e fevereiro de 2008. Em todas as ocasiões em que aves marinhas foram observadas em associações de alimentação multiespecífica com S. guianensis, dados sobre as espécies envolvidas e seus números foram obtidos. Dos 435 grupos de S. guianensis observados no EC, 38 (8,7 por cento) envolveram interações com aves marinhas. No CEP, dos 286 grupos observados, 32 (11,2 por cento) envolveram as interações mencionadas. As seguintes aves marinhas foram observadas em associações de alimentação com S. guianensis: Fregata magnificens, Sula leucogaster, Phalacrocorax brasilianus, Sterna sp. No EC, S. leucogaster foi significativamente mais observada em associação de alimentação com o boto-cinza (χ2 = 22,84; g.l. = 3 p < 0,05), enquanto no CEP não foram observadas diferenças quando comparadas as aves marinhas (χ2 = 5,78; g.l. = 3, p = 0,1223). No EC, associações de alimentação foram significativamente mais freqüentes em águas internas (χ2 = 9,52; g.l. = 2, p < 0,05) e no inverno (χ2 = 12,46; g.l. = 1, p < 0,05). Dentre estes eventos, 44,7 por cento dos grupos de associação foram compostos por mais de uma espécie. Sazonalidade nas associações de alimentação também foi observada no CEP (χ2 = 4,76; g.l. = 1, p < 0,05), com os mesmos padrões observados para o EC. As interações foram mais freqüentes na baía das Laranjeiras, CEP (χ2 = 11,65; d.f. = 2, p < 0,05). Dentre estes eventos, 74,2 por cento ...

Group size and composition of Guiana dolphins (Sotalia guianensis) (Van Bénèden, 1864) in the Paranaguá Estuarine Complex, Brazil / Tamanho e composição de grupos do boto-cinza (Sotalia guianensis) (Van Bénèden, 1864) no Complexo Estuarino de Paranaguá, Brasil

The aim of the present study was to describe the characteristics of Guiana dolphins (S. guianensis) group size and composition in the Paranaguá Estuarine Complex (25° 15' -25° 36' S and 48° 02'-48° 45' W), Paraná State, as well as to verify the existence of relationships between a given environmental variable (water depth, salinity, transparency and temperature) and group size. An area of around 124 km² was surveyed by boat from April 2006 to February 2008 in the following subsets of the estuary: Canal do Superagui (~28 km²), Pinheiros bay (~34 km²), part of Laranjeiras bay, which included the Guaraqueçaba sub-estuary (~38 km²), and part of the Mixture Section of the Paranaguá Estuarine Complex (~24 km²). In 45 survey days, a total of 147 hours were spent observing 286 groups of S. guianensis. Groups varied from two individuals to aggregations of up to 90 individuals (mean ± SD: 11.5 ± 14.4 individuals). Solitary individuals were seen only on five occasions (1.7 percent of all observations). Groups with calves (n = 247) represented 86.4 percent overall and were more common in all sub-areas when compared to groups without calves. Groups without calves were found in all sub-areas and were usually smaller and composed of up to 12 individuals. A usual group composition of 70 percent of adults and 30 percent of calves was observed considering all sub-areas and seasons. No correlations were found between group size and water temperature (Spearman's rank test, r = 0.0059, p = 0.9338), transparency (Spearman's rank test, r = 0.0597, p = 0.9333), depth (Spearman's rank test, r = 0.1421, p = 0.4698), and salinity (Spearman's rank test, r = -0.1938, p = 0.0665). While Guiana dolphin groups were seen in the entire surveyed area, group size varied significantly among the three main surveyed sub-areas (Kruskal Wallis, H2,196 = 29.85, p = 0.0000). Groups were larger in Laranjeiras bay and smaller in Canal do Superagui. The physical environment, risk ...

O objetivo do presente estudo foi descrever as características do tamanho e da composição de grupos do boto-cinza (S. guianensis) no Complexo Estuarino de Paranaguá (25° 15'-25° 36' S and 48° 02'-48° 45' O), Estado do Paraná, assim como de verificar a possível existência de relações entre uma dada variável ambiental (profundidade, salinidade, transparência e temperatura da água) e o tamanho de grupo. Uma área de aproximadamente 124 km² foi investigada com uso de barco a motor entre abril de 2006 e fevereiro de 2008 nas seguintes sub-áreas do estuário: Canal do Superagui (~28 km²), baía dos Pinheiros (~34 km²), parte da baía das Laranjeiras que incluiu o sub-estuário de Guaraqueçaba (~38 km²), e parte da Seção de Mistura do Complexo Estuarino de Paranaguá (~24 km²). Em 45 dias de investigação, um total de 147 horas foi empregado na observação de 286 grupos de S. guianensis. Numericamente os grupos variaram entre dois e 90 indivíduos (média ± DP: 11,5 ± 14,4 indivíduos). Indivíduos solitários foram observados em apenas cinco ocasiões (1,7 por cento de todas as observações). Grupos com filhotes (n = 247) representaram 86,4 por cento de todos os observados e foram mais comuns em todas as sub-áreas quando comparados com grupos sem filhotes. Grupos sem filhotes foram geralmente compostos por até 12 indivíduos e encontrados em todas as sub-áreas. Uma comum composição de grupo de cerca de 70 por cento de adultos e 30 por cento de filhotes foi observada considerando todas as sub-áreas e estações do ano. Não foram apontados correlações entre o tamanho de grupo e a temperatura (Teste de Rank de Spearman, r = 0,0059; p = 0,9338), a transparência (Teste de Rank de Spearman, r = 0,0597; p = 0,9333), a profundidade (Teste de Rank de Spearman, r = 0,1421; p = 0,4698), e a salinidade da água (Teste de Rank de Spearman, r = -0,1938; p = 0,0665). Enquanto grupos de botos-cinza foram observados ao largo de todo o estuário, seus tamanhos variaram significativamente ...

First description of corpus luteum with central cavity during pregnancy in Sotaia guianensis (Van Bénéden, 1864) - Case report / Primeira descrição de corpo lúteo cavitário gestacional em Sotalia guianensis (Van Bénéden, 1864) - Relato de Caso

O objetivo foi descrever pela primeira vez o corpo lúteo cavitário gestacional em Sotalia guianensis, espécie de golfinhocosteiro que se distribui ao longo da costa Atlântica Ocidental. Os ovários de um espécime com 196cm de comprimentocorporal, com 9,2 meses de gestação, capturado acidentalmente durante atividade pesqueira na costa norte do estado doRio de Janeiro. O material foi avaliado morfologicamente e processado para cortes em parafina, corado pela hematoxilina eeosina para microscopia. O ovário direito apresentava forma amendoada, com sulcos em uma lateral, três folículos e umcorpo lúteo polar em involução. O ovário esquerdo pesava sete vezes mais que o direito. A superfície era enrugada, com umfolículo, seis corpos lúteos e quatro albicans. O maior corpo lúteo era protruso, com diâmetro médio de 3cm e uma cavidadecentral de 1cm de diâmetro, revestida por paredes regulares e espessas, sugerindo ser um corpo lúteo em desenvolvimento.Os outros corpos lúteos eram maciços e estavam em regressão. A microscopia do corpo lúteo não demonstrou envolvimentopatológico. Esta descrição, ímpar na espécie, representa uma contribuição ao conhecimento da biologia (reprodutiva) da S.guianensis, que consta como "Dados Deficientes" na lista vermelha da União Internacional para Conservação da Natureza.

This is the first study to describe the corpus luteum with central cavity during pregnancy in Sotalia guianensis, a coastal dolphin species distributed along the Atlantic Ocean coast. The material analyzed was a pair of ovaries of a 196-cm-long female was 9.2 months pregnant, accidentally captured on the north coast of the state of Rio de Janeiro, Brazil. Both ovaries were measured and inspected for anatomic structures. After, ovaries were process in paraffin-embedded and stained with hematoxylin and eosin for microscopy. The left ovary had a wrinkled outside, one follicle, six corpora lutea and four corpora albicans. The largest corpus luteum was protruded, 3 cm long in mean diameter with one central cavity. It was lined by uniform thick walls and peripheral vascularization, which suggests that the corpus luteum is under development. The left ovary was deformed due to the presence of corpus luteum, which accounted for the seven-fold higher weight as compared to the right ovary. The histology of the corpus luteum did not evince any pathologic status of the material. This description, the first ever made for the species, offers a contribution to the existing knowledge about the reproduction biology of S. guianensis, which is a member of the "Insufficient Data" Red List prepared by the World Conservation Union.

Occupation pattern of a harbor inlet by the estuarine dolphin, Sotalia guianensis (P. J. Van Bénéden, 1864) (Cetacea, Delphinidae)

The occupation pattern of Sotalia guianensis in São Francisco do Sul harbor inlet, in Babitonga bay, southern Brazil, was studied between September 1996 and June 1998. A total of 200 h of naturalistic observations and 141.2 h of estuarine dolphin systematic observations were made using binoculars 7 x 50. At each three minutes interval, data about number of individuals and behavior were registered. The population used the harbor inlet intensively, mainly for fishing activities. Ebb tide was responsible for a higher occupation index. Considering the months analyzed, the higher occupation index occurred in May, and in January the lower occurrence was observed. The mean group size was four individuals.

Os padrões de ocupação da enseada do porto de cargas de São Francisco do Sul, no interior da Baía da Babitonga, sul do Brasil, pela população de botos cinza Sotalia guianensis foi estudada entre setembro/1996 e junho/1998. Totalizou-se 200 horas de observações naturalísticas e 141.2 horas de observação sistemática na área, utilizando-se binoculares 7 x 50. Foram registrados a cada intervalo de 3 minutos dados sobre o número de indivíduos presentes e comportamento. A população utilizou intensamente a enseada do porto, principalmente para atividades de pesca. A maré enchente foi responsável por maiores taxas de ocupação. Dentre os meses analisados, maio foi o mês com maior média nas taxas de ocupação, e janeiro o mês de menor ocorrência. O tamanho de grupo médio na área foi de quatro indivíduos.

Descrição do comportamento de superfície do boto cinza, Sotalia guianensis, na Praia de Pipa - RN / Description of the surface behaviour of marine tucuxi, Sotalia guianensis, at Pipa Beach - RN

O estudo do comportamento animal é uma área de pesquisa consolidada, que cresceu e se diversificou em vários países e que deu origem a disciplinas e abordagens de investigação, como a Etologia, a Ecologia Comportamental, a Neuroecologia, a Psicologia e a Psicologia evolucionista. No estudo do comportamento animal, o etograma é a base para estudos comportamentais de espécies pouco conhecidas, como também para comparar comportamentos de populações distintas de uma mesma espécie. Tradicionalmente, um etograma descreve de forma detalhada eventos comportamentais realizados por indivíduos de uma espécie. O presente estudo apresenta um etograma dos eventos comportamentais realizados na superfície por uma espécie de golfinho costeiro, boto cinza, na praia de Pipa - RN.

Research in animal behavior is a consolidated area whose development and diversification in several countries have originated some subjects and investigation approaches, such as Ethology, Behavior Ecology, Neuroecology, Psychology and Evolutionist Psychology. In the study of animal behavior, the ethogram is the foundation for studies on behavior patterns of distinct populations of the same species. An ethogram traditionally describes behavioral events performed by individuals of the same species in detail. This study presents an ethogram of behavioral events performed on surface by a costal dolphin known as the gray dolphin (Marine Tucuxi Dolphin), at Pipa Beach, RN.