Paulo Henrique Ott

Habitat use patterns of franciscana dolphins (Pontoporia blainvillei) off southern Brazil in relation to water depth

The patterns of habitat use by the franciscana dolphins (Pontoporia blainvillei) along its distribution are poorly known. This study investigates the patterns of habitat use with respect to depth for 181 individuals of different age, size, gender and reproductive condition off Rio Grande do Sul, southern Brazil. The results reveal that franciscanas are very homogeneously distributed according to depth. Individuals from all lengths utilize nearly the entire range of depths of the surveyed area. Larger or older animals do not use deeper waters than younger animals, indicating that body size and age are not limiting factors for franciscanas that occupy deeper or offshore waters. Gestation seems to not cause a change in the distribution of females. Although the sex-ratio of the overall data did not vary from 1:1 in different depth intervals, a small-scale comparison between the northern and southern coast demonstrated the existence of some kind of sexual segregation. Franciscana by-catch in Rio Grande do Sul is not sustainable and it is agreed that management procedures are needed. Nevertheless, the available data on species distribution do not allow the designing of a protected area in order to minimize the by-catches of a particular sex/reproductive class.

Humpback whales washed ashore in southeastern Brazil from 1981 to 2011: stranding patterns and microbial pathogens survey

In the Southwest Atlantic Ocean the wintering breeding ground of Megaptera novaeangliae is located in northeastern coast of Brazil, mainly in the Abrolhos Bank (16°55′ S, 38°50′ W) and its surroundings. During migratory percussion, events of strandings are thought to occur. A total of 58 stranded humpback whales were recorded between 1981 and 2011 along the coast of the Rio de Janeiro state, Brazil. The number of strandings in 20 years (1992–2011) increased during the period of study, with a mean of 2.6 events per year. In 2010 a peak occurred with 13 records of strandings. Most of them occurred preferably in the southern half of the study area, or in the southeast area of Rio de Janeiro state. Three cases of entanglement were found, two of these involving calves with less than eight meters of body length. Stranding events were more frequent during winter and spring. No statistical differences were found between age categories, but 33% were classified as “dependent calf” (< 8 m length). Males stranded more often than females. Only one whale out of 16 specimens that had the stomach contents examined presented food remains, but comprising only two cephalopod beaks of the squid Doryteuthis sanpaulensis. Bacteriological survey of Vibrionaceae and Aeromonadaceae agents in three live stranded whales on the Brazilian coast indicated evidence of animal impairment that resulted or were associated with the cause of death and stranding event.

Epidemiology of lobomycosis-like disease in bottlenose dolphins Tursiops spp. from South America and southern Africa

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.

First record of partial albinism in two catfish species of Genidens (Siluriformes: Ariidae) in an estuary of Southern Brazil

ABSTRACT This study reports the first occurrence of partial albinism in two species of Ariidae: Genidens barbus and Genidens planifrons from an estuary of Southern Brazil. Possible causes of the simultaneous occurrence of three specimens with partial albinism are discussed, including random genetic alterations, chronic contamination effects and small effective population size, which may favor the expression of the recessive albino gene. Key words: Estuarine fishes, Genidens barbus , Genidens planifrons , leucism * Author for correspondence: mateusleal1977@gmail.com INTRODUCTION Albinism is a genetic disorder produced by an autosomal recessive gene in the homozygous state caused by the deficiency in melanin production (Westerman and Birge 1978). The true albinism is recognized by the total lack of melanin, thus determining the pink or yellowish body color and red eyes (Sazima and Pombal-Jr. 1986). However, there is another form of depigmentation considered partial albinism (Sazima and Pombal-Jr. 1986; Klug and Cummings 1999). A recent term, known as leucism, has also been introduced to the animals with abnormal skin pigmentation but normal eye color (Bechtel 1995). Recently, it has also been used in ichthyology (Clark 2002). In natural environment, there are several reports of total or partial albinism in freshwater fishes (Westerman and Birge 1978; Sazima and Pombal-Jr. 1986; Ueda et al. 2007; Jeffery 2009) and marine fishes (Bearez 2002; Simon et al. 2009; Piorski and Nunes 2010). Some cases of total or partial albinism in Siluriformes have been reported, e.g., Ictalurus punctatus (Westerman and Birge 1978), Trichomycterus itacarambiensis (Trajano 1997), Rhamdella minuta (Sazima and Pombal-Jr. 1986) Schizolecis guntheri (Brito and Caramaschi 2005), Ameiurus catus (Britton and Davies 2006) and Phreatobius cisternarum (Shibatta et al. 2007). Frequently captured albino fish are only reported in aquarium magazines and local newspapers (Sazima and Pombal-Jr. 1986). Catfish of the genus Genidens belongs to Ariidae family and comprises G. barbus (LACEPEDE, 1803), G. genidens (CUVIER, 1829), G. machadoi (MIRANDA-RIBEIRO, 1918) and G. planifrons

Occurrence of the Atlantic spotted dolphin, Stenella frontalis , in southern Abrolhos Bank, Brazil

daniel danilewicz, paulo h. ott, eduardo secchi, artur andriolo and alexandre zerbini Laboratorio de Ecologia e Conservacao de Mamiferos Marinhos (ECOMMAR), Universidade Estadual de Santa Cruz, Departamento de Ciencias Biologicas, Rodovia Ilheus/Itabuna, km 16, Ilheus, BA, 45662-900, Brazil, Instituto Aqualie, Rua Edgard Werneck 428/32, Rio de Janeiro, RJ, 22763-010, Brazil, Grupo de Estudos de Mamiferos Aquaticos do Rio Grande do Sul (GEMARS), Avenida Tramandai, 976, Imbe, 95625-000, Rio Grande do Sul, Brazil, Departamento de Zoologia, Instituto de Ciencias Biologicas, Universidade Federal de Juiz de Fora, Minas Gerais, Brazil, Universidade Estadual do Rio Grande do Sul (UERGS), Laboratorio da Biologia e Conservacao de Aves e Mamiferos Aquaticos, Avenida Mostardeiro, 3635, Cidreira, 95595-000, Rio Grande do Sul, Brazil, Laboratorio de Mamiferos Marinhos, Instituto de Oceanografia, Universidade Federal do Rio Grande (FURG), Rio Grande, RS, Brazil, National Marine Mammal Laboratory, Alaska Fisheries Science Center, NOAA Fisheries, 7600 Sand Point Way NE, Seattle, Washington 98115, USA, Cascadia Research Collective, 218 2 4th Avenue, Olympia, WA, 98501, USA

MHC class II expression in skin biopsies from the franciscana dolphin Pontoporia blainvillei and the southern right whale Eubalaena australis

Presently, there is no information about the functionality of the immune system in the franciscana dolphin (Pontoporia blainvillei), a small dolphin from southern Brazil. As in the case of the franciscana, the population of southern right whale (Eubalaena australis) which inhabits Brazilian waters has not yet been surveyed in what concerns MHC expression. For the first time it was possible to observe the DQB gene expression in skin of these two species of cetacean using RT-PCR. Skin pieces of the animals were collected to RNA extraction. The fragment corresponding to DQB exon 2 was amplified, cloned and sequenced. A total of five alleles were found, one to franciscana and four to southern right whale. The observed d N /d S ratio of 2.77 (P = 0.03) suggests that this gene is under balancing selection pressure (positive Darwinian selection). The sequences indicate that, in both species analysed, the DQB gene is functional.

Population genetic structure of the South American Bryde's whale

A genetic analysis based on mitochondrial DNA control region sequences was conducted to investigate both species identity and populations genetic structure of South American Brydes whales. The genetic analysis was based on historical, biopsy and stranding samples from Chile (n= 10) and Brazil (n= 8). For comparative purposes published sequences of the Brydes whales from different localities of the Indian and Pacific Oceans (including Peru, n= 24) were incorporated into the analysis. Results of the phylogenetic analysis identified the Brydes whales of South Ameri ca as Balaenoptera brydei. No statistically significant genetic differentiation was found between Chilean and Peruvian Brydes whales. However, striking differences were found between western South Atlantic (Brazil) and eastern South Pacific (Peru and Chile) animals. In addition, striking genetic differences were found between all South American localities and those from the western North Pacific, Fiji and Java. These results suggest movement of B. brydei in the eastern South Pacific in the latitudinal range corresponding to Chile and Peru. These results also suggest no or very limited mov ement of whales between the South Pacific and the South Atlantic Oceans. This is consistent with the notion that B. brydei is not distributed further south of approximately 40oS on both sides of South America.

Bottlenose dolphin communities from the southern Brazilian coast: do they exchange genes or are they just neighbours?

The genetic structure of bottlenose dolphin communities found along the southern Brazilian coast is reported in this study. Genetic structure analysis using biopsy samples from free ranging dolphins and tissue samples from stranded dolphins revealed a fine-scale population structure among three distinct groups. The first genetically distinct group was composed of resident dolphins of Laguna with a high degree of site fidelity. The second group was composed of one photo-identified dolphin, previously recognised by its interaction with fishermen, and dolphins that stranded near the mouth of Tramandai Lagoon. Moderate nuclear and low mitochondrial gene diversity was found in dolphins of those coastal communities, whereas most of the dolphins stranded along the coast showed markedly higher levels of gene diversity at both markers. These stranded dolphins of unknown origin formed the third distinct group, which may be part of a larger offshore community. These results demonstrate the presence of at least three bottlenose dolphin clusters along this portion of the Brazilian coast, with the coastal specimens appearing to be only neighbours of a larger offshore community that eventually strands along the coast, highlighting the importance of the establishment of management and conservation measures for the species at a local scale.

Ancient female philopatry, asymmetric male gene flow, and synchronous population expansion support the influence of climatic oscillations on the evolution of South American sea lion (Otaria flavescens)

The South American sea lion (Otaria flavescens) is widely distributed along the southern Atlantic and Pacific coasts of South America with a history of significant commercial exploitation. We aimed to evaluate the population genetic structure and the evolutionary history of South American sea lion along its distribution by analyses of mitochondrial DNA (mtDNA) and 10 nuclear microsatellites loci. We analyzed 147 sequences of mtDNA control region and genotyped 111 individuals of South American sea lion for 10 microsatellite loci, representing six populations (Peru, Northern Chile, Southern Chile, Uruguay (Brazil), Argentina and Falkland (Malvinas) Islands) and covering the entire distribution of the species. The mtDNA phylogeny shows that haplotypes from the two oceans comprise two very divergent clades as observed in previous studies, suggesting a long period (>1 million years) of low inter-oceanic female gene flow. Bayesian analysis of bi-parental genetic diversity supports significant (but less pronounced than mitochondrial) genetic structure between Pacific and Atlantic populations, although also suggested some inter-oceanic gene flow mediated by males. Higher male migration rates were found in the intra-oceanic population comparisons, supporting very high female philopatry in the species. Demographic analyses showed that populations from both oceans went through a large population expansion ~10,000 years ago, suggesting a very similar influence of historical environmental factors, such as the last glacial cycle, on both regions. Our results support the proposition that the Pacific and Atlantic populations of the South American sea lion should be considered distinct evolutionarily significant units, with at least two managements units in each ocean.

Marine debris ingestion by the South American Fur Seal from the Southwest Atlantic Ocean

In this paper, we examined the ingestion of marine debris (MD) in South American fur seals (SAFS), Arctocephalus australis, found dead in coastal beaches of northern Argentina and southern Brazil. Seven percent of 133 SAFS analyzed presented marine debris in their stomach (n=10), with no differences between sampling countries (Brazil n=7, Argentina n=3) and sexes (female=3; male=6). However, significant differences were observed between ages classes, with MD exclusively present in stomach contents of young specimens. Plastics represents 90% of MD ingested by the SAFS, whereas regarding the source, fishery-related items (e.g. monofilament lines) were the main MD (70%), with a lesser proportion of packaging (e.g. pieces of bags). Low numbers but large size pieces of MD were found in each stomach affected. Negative effects on the individuals could not be fully evaluated. Therefore, the potential impacts of the marine debris to the SAFS deserve further elucidation.