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Seabirds, particularly albatrosses, are among the most threatened birds as a result of their continuous exposure to anthropic pressures including interaction with commercial fisheries, climate change and pollution. Several studies that have focused on the spatial distribution of foraging seabirds have identified a certain level of segregation between age classes.The black‐browed albatross Thalassarche melanophris is the most abundant albatross species in the South‐west Atlantic Ocean and the main pelagic seabird interacting with a range of fishing fleets. There is a considerable lack of knowledge about the biology of immature individuals and on habitat suitability of the species during non‐breeding season (winter).The aim of this study was to assess the foraging habitat suitability of the black‐browed albatross in the South‐west Atlantic during the austral winter, analysing differences between adults and immatures individuals.Habitat suitability models were based on foraging locations recorded by 15 satellite transmitters deployed on six adults and nine immature individuals between 2011 and 2015. Remotely sensed oceanographic data were used to characterize suitable foraging habitat for the albatrosses.Differences were found in foraging habitat suitability by age class, with adult selecting areas located in deeper waters over the continental shelf break as well as in neritic zones under cooler water temperatures, whereas immature individuals foraged chiefly off coastal waters having more moderate temperatures.Knowing habitat suitability and segregation patterns within‐species is key for the conservation of critical marine habitats given that, by only considering one age class, other important habitats would be neglected and not considered in conservation efforts to mitigate threats such as incidental mortality. It is important to include all age classes when studying patterns of associations with threats, such as fishing activity as a proxy of risk of bycatch, and for the development of Marine Protected Areas. [ABSTRACT FROM AUTHOR]

Egg capsules of the multispine skate, Bathyraja multispinis (Norman, 1937), described here for the first time, are larger (180 mm in length without horns) than those of any Bathyraja species from the South-west Atlantic Ocean (SWA). The capsule’s surface texture is relatively smooth by the presence of woven-like fibres. However, below the fibres, it is rough to the touch by the presence of longitudinal ridges and prickles of different shapes and sizes, ending in two or more digitiform projections. An identification key to all described Bathyraja egg capsules occurring in the SWA from 34° to 55°S is provided. [ABSTRACT FROM AUTHOR]

Fish processing generates plenty of waste that is directly discarded in open‐air dumps and water sources, or treated in the same way as urban solid waste, causing serious pollution problems. The waste represents a significant source of high‐value bioproducts with potential applications in different industrial processes such as the production of feed, fertilizers, biodiesel and biogas, detergent additives and cosmetics. The objective of this study was to characterize and compare specific activities under different pH values and temperature conditions of acid and alkaline proteinases and viscera yield from the following fish species: Argentine hake Merluccius hubbsi, Brazilian flathead Percophis brasiliensis, Brazilian codling Urophycis brasiliensis and Stripped weakfish Cynoscion guatucupa. Individuals were fished off the coast of Mar del Plata (Argentina) by a commercial fleet and the viscera were immediately extracted and kept on ice until use. Stomach proteinases from four species had the highest activity at pH 2, with stability in the range of pH 2–4. The optimum pH was 11.5 from intestinal enzymes of C. guatucupa, M. hubbsi and P. brasiliensis and 9.5 from intestinal enzymes of U. brasiliensis. Alkaline proteinases from all species were highly stable in the range of 7–11.5. The optimum temperature of stomach proteinases from the four species studied were 30 and 50°C, with stability at 10 and 30°C during 150 min. The optimum temperature of intestinal enzymes from the tested species were 50°C with high stability at 10 and 30°C during 150 min. Alkaline proteinase from all species and acid proteinases from C. guatucupa were inactive at 70°C after 150 min, while there was a residual activity lower than 5% at 80°C on pre‐incubated stomach enzymes of M.hubbsi, P. brasiliensis and U. brasiliensis after 5, 10 and 20 min, respectively. Digestive proteinases recovered in this study could be appropriate for technological usage, reducing manufacturing costs, obtaining revenue from fishery wastes, and contributing to the reduction of environmental pollution. [ABSTRACT FROM AUTHOR]

The present note describes the occurrence of Rhytidodoides intestinalis and Rhytidodoides similis (Digenea: Rhytidodidae) in the gallbladder of two juvenile green turtles (Chelonia mydas - Testu- dines, Cheloniidae) found on the coast of Brazil. Both were detected in gallbladder and intestine of green turtles: Rhytidodoides similis (United States, Panama, Costa Rica and Brazil) and R. intestinais (United States, Panama and Costa Rica). This note is the first report of R. intestinalis in Brazil and South-West Atlantic Ocean. Also the histological lesions caused by the parasites in one gallbladder are described.

Sexual segregation in habitat use occurs when sexes differ in their use of the physical environment and is widely reported among seabirds. The Black-browed Albatross (Thalassarche melanophris) is one of the most abundant seabird species in the south-west Atlantic, but whether the sexes differ in their habitat selection during winter remains unknown. Here, we tested for sexual segregation in adult and immature Black-browed Albatrosses during winter. Movement data from 21 satellite-tracked Black-browed Albatrosses across the south-west Atlantic Ocean between 2011 and 2015 were used to determine suitable foraging habitat for males (n = 7) and females (n = 14) using habitat selection models. Sexual segregation was then assessed using an index of niche overlap for immature and adult age classes. Variables with the highest importance in habitat selection models across all groups were depth and sea surface temperature. The highest probabilities of occurrence were in shallow waters and intermediate surface temperatures. No sexual segregation was found which may be because of the large abundance of prey in the region and moderate energy requirements during the non-breeding season. These results are relevant for spatially explicit conservation management in this region, including the designation of marine protected areas. Indeed, bycatch in fisheries is a major threat to seabirds in this area, and foraging behaviour and performance in winter of this keystone species will influence their future reproductive performance. [ABSTRACT FROM AUTHOR]

This study reports the results of 5 years of monitoring reef fish post‐larvae using light traps in the Bay of Tamandaré, north‐east Brazil. An annotated checklist of pre‐settlement fish species, their frequency of occurrence and taxonomic characteristics are provided. In total, 4,422 post‐larval fishes belonging to 36 families, 56 genera and 76 species were captured. The most species‐rich families were Carangidae (7), Lutjanidae (6) and Pomacentridae (4), while the families Gerreidae (30.47%), Holocentridae (16.54%), Blenniidae (12.01%), Labrisomidae (8.36%), Lutjanidae (8.29%) and Acanthuridae (5.95%) were the most abundant. This is the first study of the taxonomic diversity and assemblage structure of settlement‐stage reef fishes in the tropical south‐west Atlantic Ocean. Although a few common species were not captured due to selectivity of light traps, the composition and taxonomic diversity of this first collection suggests that light traps are useful for studies of the early life history of a wide range of pre‐settlement reef fishes. [ABSTRACT FROM AUTHOR]

A study was conducted over eight consecutive days in February 2010 in which daily variations in the vertical distributions of heterotrophic bacteria, mesozooplankton and ichthyoplankton at 1–1200 m in the South-western Atlantic Ocean were investigated. Diurnal and nocturnal samples were collected at an oceanographic station at four regional depths: Tropical Water (TW) (1 m), South Atlantic Central Water (SACW) (250 m), Antarctic Intermediate Water (AAIW) (800 m) and Upper Circumpolar Deep Water (UCDW) (1200 m). Bacterial, mesozooplankton and larval fish densities significantly differed between sample depths but not between sampling tow times. In total, 154 zooplankton species and 18 larval fish species were identified. The highest number of taxa was obtained from the night-time TW trawls. This depth zone had the highest densities of mesozooplankton, larval fish and bacterioplankton (auto and heterotrophic), associated with the highest temperature and salinity and the lowest inorganic nutrient concentrations. Two sample groups were identified based on their mesozooplankton and larval fish compositions: night-time TW and other water masses (daytime TW, SACW, AAIW and UCDW). Thirty-two indicator species were detected in night-time TW. The copepod Nullosetigera impar was, to the best of our knowledge, identified for the first time on the Brazilian coast. Our results showed significant variability in the abundance and vertical distribution of mesozooplankton, bacterioplankton and larval fish along the water column in an oceanic area. We have provided new data and insights on the composition and vertical distribution of mesozooplankton, larval fish and bacterioplankton in deep waters in the South-western Atlantic Ocean. [ABSTRACT FROM AUTHOR]

Activities displayed by animals are usually cyclic, and fluctuations in behavioural repertoires can be observed on a daily or seasonal timescale. The present study describes daily and seasonal variations in the aerial events – such as leaps, spins and slaps with body parts – by spinner dolphins in Baía dos Golfinhos, Fernando de Noronha Marine National Park, in Brazil. To measure aerial events by dolphins, we compiled and analysed data collected from January 2006 to December 2010. A total of 113,027 aerial events were recorded during 1431 days of land-based daytime observations. Our results show that the frequency of aerial events was positively correlated with the number of dolphins in the bay. The relative frequency of aerial events was higher in the rainy season, when compared with the dry season. Aerial activities also varied throughout the day, with dolphins being more active in the morning, specifically from 8:00 a.m. to 8:59 a.m., regardless of the season. [ABSTRACT FROM AUTHOR]

This study aimed to describe the ethnoecology of the franciscana (Pontoporia blainvillei) using the traditional knowledge of artisanal fishermen in the villages of Peças Island (VPI) and Superagui Island (VSI) in the World Heritage listed Paranaguá Estuarine Complex, Brazil. Between March and September 2012, 90 fishermen were interviewed (VPI – 40; VSI – 50) using a semi-structured questionnaire. Using Fuzzy logic (MATLAB 7.6) it was verified the species is easily recognized by body size, colour and occurrence area (VPI – 87.5%; VSI – 38.0%). Fishermen most frequently identified adults and young franciscanas in groups of two to five individuals (VPI – 40.0%; VSI – 58.0%). Adults were sighted throughout the year, while the young were restricted to summer and winter. Five common behavioural ethno categories were described: ‘eat’ (VPI – N = 15; VSI – N = 1); ‘float/sink/dive’ (VPI – N = 34; VSI – N = 12); ‘breathe’ (VPI – N = 11; VSI – N = 5); ‘mothers surrounding the shoal, play caught up and the youth captures’ (suggesting care parental related with feeding of infant) (VPI – N = 1; VSI – N = 2); and ‘to play’ (VPI – N = 6; VSI – N = 1). The information from the fishermen highlights the use of the area by franciscana for feeding and reproduction and these data are comparable with the literature. These results extend the knowledge about the species in an area of ecological interest and the traditional knowledge, but also illustrate the benefits of engaging fishermen to promote collaboration in scientific and management processes. [ABSTRACT FROM AUTHOR]

Five adult paralichthyid specimens with various kinds of abnormalities are reported from the south‐west Atlantic Ocean. These abnormal flatfish specimens represent the first records of wholly ambicoloured Paralichthys orbignyanus specimens having a deep notch between the eye and dorsal fin and a partially albinistic specimen having skeletal deformities and only the second record of an almost totally ambicoloured specimen. We also report the first observation of reversal in Paralichthys patagonicus and an almost totally ambicoloured, reversed Xystreurys rasile. [ABSTRACT FROM AUTHOR]

Egg cases of the narrowmouthed catshark Schroederichthys bivius were recorded entangled with sponges, corals and tubeworms at different sites in the south-west Atlantic Ocean. This work sheds light on the importance of benthic invertebrates in the life cycle of oviparous chondrichthyan species. [ABSTRACT FROM AUTHOR]

The composition of the larval fish assemblage in the sound-scattering layer of the continental shelf waters off the coast of south-eastern Brazil (12 and 22° S), a research project that is part of the Brazilian programme Avaliação do Potencial Sustentável de Recursos Vivos na Zona Econômica Exclusiva (REVIZEE), is described. Samples were collected during daylight hours and at dusk at five oceanographic stations in the winter of 1999 using an Isaacs-Kidd Midwater Trawl (IKMT). The oceanographic stations were chosen based on the detection of plankton layers by acoustic observation. A total of 2192 larval fish were identified, comprising 52 families and 62 species. Maurolicus stehmanni (Sternoptychidae) was the most abundant species found within the study area, comprising 18·5% of all identified larvae, followed by Psilotris celsus (Gobiidae) at 10·9%. [ABSTRACT FROM AUTHOR]

This study, carried out between spring 2012 and winter 2014, characterized the sexual development and reproductive cycle of Myliobatis goodei and Myliobatis ridens in the extreme south of Brazil to support future management and conservation plans. Ninety-five specimens of M. goodei (24 males and 71 females) and 175 M. ridens (24 males and 151 females) were sampled. Female M. goodei attained disc-width-at-50% maturity ( WD50) at 683 mm. Uterine fecundity was four to five embryos. The largest male recorded, a mature individual, had a disc width of 650 mm. In M. ridens, WD50 was 662 mm. Uterine fecundity varied from one to eight embryos. The largest male on record was a maturing 590 mm WD individual. The hepato-somatic index was higher in autumn in females of M. goodei, and in the summer in M. ridens. The gonado-somatic index and the largest vitellogenic follicle diameter were higher in spring in both species. Pregnant females of both species were recorded during spring, although for M. ridens, these females also occurred in summer. Embryos had WD of 61-218 and 40-236 mm for M. goodei and M. ridens, respectively. The incidence of pregnant females in southern Brazil in spring-summer coincides with the small-scale beach artisanal fisheries season peak, when M. goodei and M. ridens suffer fishing mortality, while using the coastal shallow areas in the warmer periods (spring-summer) to give birth. [ABSTRACT FROM AUTHOR]

The total lengths (LT) of 193 males (209-556 mm) and 130 females (275-515 mm) of Amblyraja doellojuradoi, a commercial by-catch species on the Argentinean continental shelf, which are increasingly retained, were analysed. No sexual dimorphism was observed in the LT at which 50% of individuals were sexually mature; males matured at 448mm and females at 411 mm, c. 80 and 82% of maximum LT. The hepato-somatic index was similar among sexes, but significantly different between maturity stages, being lower in mature than immature specimens. Males had no seasonal difference in the hepato-somatic index and females had the lowest index in autumn. The gonado-somatic index was lower in males than in females and significantly higher in mature than immature specimens of both sexes. Males had the highest index in autumn and females had no seasonal difference. Collectively, these results would indicate that A. doellojuradoi breeds in autumn. [ABSTRACT FROM AUTHOR]

The Falkland Islands fishing industry is unique, as 60-80% of its annual catch consists of two squid species, Illex argentinus and Doryteuthis gahi. Short annual life cycles make both species susceptible to intra-annual environmental changes, resulting in large biomass fluctuations that must be addressed in management of the stocks. In the D. gahi fishery, short chains of communication between science, management and industry allow effective cooperation in the interest of long-term sustainable exploitation. The industry is responsive to short-notice requests for in-season information about the fishery. Management takes into account both scientific advice and industry recommendations, through ongoing consultations before and during the fishing seasons. As a result of this cooperation, D. gahi is one of the best managed squid fisheries in the world with local fishing companies being amongst the largest and most profitable enterprises in the Falklands economy. The I. argentinus fishery has the same potential, but a further level of cooperative management is needed as this squid is a straddling stock between several countries and the high seas. Development of a regional fisheries management organization in the South Atlantic Ocean is required to control multilateral exploitation and ensure long-term sustainability of I. argentinus stocks. [ABSTRACT FROM AUTHOR]

The Falkland Islands fishing industry is unique, as 60-80% of its annual catch consists of two squid species, Illex argentinus and Doryteuthis gahi. Short annual life cycles make both species susceptible to intra-annual environmental changes, resulting in large biomass fluctuations that must be addressed in management of the stocks. In the D. gahi fishery, short chains of communication between science, management and industry allow effective cooperation in the interest of long-term sustainable exploitation. The industry is responsive to short-notice requests for in-season information about the fishery. Management takes into account both scientific advice and industry recommendations, through ongoing consultations before and during the fishing seasons. As a result of this cooperation, D. gahi is one of the best managed squid fisheries in the world with local fishing companies being amongst the largest and most profitable enterprises in the Falklands economy. The I. argentinus fishery has the same potential, but a further level of cooperative management is needed as this squid is a straddling stock between several countries and the high seas. Development of a regional fisheries management organization in the South Atlantic Ocean is required to control multilateral exploitation and ensure long-term sustainability of I. argentinus stocks. [ABSTRACT FROM AUTHOR]

The hourglass dolphin, Lagenorhynchus cruciger, is one of the smallest cetaceans found in Antarctic waters. Although frequently observed, this is one of the least studied species of dolphin. In this study, we investigate the occurrence of hourglass dolphin in the South-West Atlantic and Southern Ocean from 42°S to 63°S and characterize the oceanographic and environmental features associated with their occurrence. Sighting data were collected during two scientific cruises in December 2009 and January and February 2011 and integrated into a geographical information system with environmental variables such as sea surface temperature, ocean colour, depth, distance to oceanographic fronts and distance from shore. We used a principal component analysis (PCA) to identify patterns in data and a non-hierarchic cluster analysis ( K means) to classify observations into groups. A total of 19 sightings (96 individuals) were recorded. Group size ranged from one to twelve dolphins (mean 5.05). We could differentiate two groups in relation to the environmental conditions where animals were found, one group occurring in shallow coastal waters and the other occurring in deeper and colder waters further offshore. The present study contributes novel information on environmental measures associated with hourglass dolphin distribution in the South-West Atlantic and Southern Oceans. Additionally, it includes relatively high sighting clusters of this species in two highly productive and biodiverse areas (Burdwood Bank/Isla de los Estados and the South Shetland Islands). [ABSTRACT FROM AUTHOR]

Seasonal changes in relative abundance and biomass of nektonic predators were analysed on the eastern Patagonian Shelf and continental slope; one of the most productive large marine ecosystems of the southern hemisphere. Several migratory types were revealed for species belonging to either temperate or sub-Antarctic faunas. Despite high productivity, only a few large nektonic predators spend their entire life cycle on the eastern Patagonian Shelf and use only a small proportion of the meso-nektonic resource. Most of the resource is exploited by non-resident nektonic migrants, which move to the area from distant spawning grounds. Pelagic and demersal sharks and skates, the squid Illex argentinus, tunas and gadoids migrate to the eastern part of the Patagonian Shelf to feed at different times of the year; arriving in seasonal waves according to their life cycle and spawning seasonality. Some deepwater fishes and squid migrate onto the shelf as juveniles to harvest the resource, and then return to deepwater habitat as adults. It is hypothesized that the large biomass of meso-planktonic and meso-nektonic consumers prevents most higher-trophic level predators from establishing spawning populations in this area, as their larvae and fry would be overwhelmed by predation. Instead, the higher-trophic level predators establish spawning and nursery grounds elsewhere and arrive to feed on the meso-planktonic and meso-nektonic resources after they have outgrown their own stages of predation vulnerability. [ABSTRACT FROM AUTHOR]

The eastern Patagonian Shelf and continental slope of the south-west Atlantic Ocean support a high biodiversity and abundance of skates. In this study, meso-scale differences in the assemblages, spatial and seasonal distributions of skates are revealed among six habitat zones of the eastern Patagonian Shelf characterized by distinctive oceanographic conditions. Most skates belonged to temperate fauna, and their abundance was much greater in habitats occupied by temperate waters (north-western outer shelf) or mixed waters (northern slope) than in habitats occupied by sub-Antarctic waters (SASW) (south-eastern outer shelf and southern slope). Sub-Antarctic skates were not abundant on the shelf even in habitats occupied by SASW, occurring mainly in deep areas of the lower continental slope. The majority of temperate skates migrated seasonally, shifting northward in winter and spreading southward with warming waters in summer. Most temperate species had two peaks in female maturity (mainly spring and autumn) and spawned in the same habitats where they fed. It is hypothesized that the high biodiversity and abundance of skates on the Patagonian Shelf and Slope are due to the practical absence of their natural competitors, flatfishes, which occupy similar eco-niches elsewhere. [ABSTRACT FROM AUTHOR]

Stomach content analyses were performed in 28 dolphins stranded between 1994 and 2007 on the beaches of Rio de Janeiro State (23°06′S 44°18′W/22°14′S 41°54′W), Brazil, comprising six delphinid species: Stenella frontalis (N = 10), Steno bredanensis (N = 7), Tursiops truncatus (N = 4), Delphinus delphis (N = 5), Lagenodelphis hosei (N = 1) and Stenella coeruleoalba (N = 1). Fish otoliths and cephalopod beaks were used to identify the prey species and to estimate the original length and weight. Seven different cephalopod species from six families and 15 fish species belonging to 10 families were identified. Although the fish contribution could be underestimated, cephalopods constituted the group of higher importance, revealing that these invertebrates may represent an important source of energy for delphinids in the region. In this context, the squid Loligo plei should be highlighted due to its important contribution. Most preys were coastal and demersal, and such consumption could indicate coastal foraging habits of the quoted dolphin species. Although dolphins consumed many species of prey in common, they fed on different size-classes of prey. The foraging area of the dolphins could be the same region used by fishing operations, which would represent a risk for incidental capture. [ABSTRACT FROM PUBLISHER]

Rafting is proposed as the mechanism of dispersal influencing the speciation and population structure of Hippocampus. Recently, rafting was confirmed in Hippocampus patagonicus by the direct observation of juveniles attached to floating debris. This study discusses the implications of the record of an individual in deep waters, suggesting that the species can disperse away from their coastal populations. [ABSTRACT FROM PUBLISHER]