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Size at maternity and size at maturity of the blue shark Prionace glauca were studied from samples collected during ten commercial longline fishing cruises off southern Brazil and in adjacent international waters. The sharp increase of the amplitude of the values of reproductive variables at a given fork length (FL) was evidence that from that FL reproduction occurred. Thus, we calculated the proportion of mature sharks in FL classes to estimate the median size at maturity. The accelerated growth of the claspers started before the beginning of the testis maturation and semen production, whereas the accelerated development of the ovary and the oviducal glands started simultaneously. Although most females with mating marks were mature, few had sperm stored in the oviducal glands. The population parameter of size at 50% of maturity was estimated at 171.2 cm FL for females and 180.2 cm FL for males. The median size at maternity was estimated in 193.9 cm FL and half of the females with five to six years old were recruited for reproductive phase of life. As most shark species, P. glauca in the Southwest Atlantic reach maturity at about three-fourths of its maximum size and half of its maximum age. Median litter size was 33 embryos. A positive not significant linear relationship between the uterine fecundity and the size of the pregnant female was observed.

Compreender a distribuição espacial de espécies vulneráveis a exploração pesqueira pode subsidiar ações de manejo e conservação. O objetivo deste estudo foi mapear possíveis habitats essenciais para riqueza de elasmobrânquios no sul do Brasil. Os dados são oriundos de cruzeiro científico realizado em fevereiro de 2005 entre o arroio Chuí (33°45'S) e o Cabo de Santa Marta Grande (28°36'S). As informações disponíveis são posições georeferenciadas de 64 estações oceanográficas, a quantificação das capturas de elasmobrânquios e teleósteos com pesca de arrasto de fundo e o registro dos parâmetros ambientais de profundidade, temperatura e salinidade. Os dados foram ajustados a um Modelo Linear Generalizado (GLM) Bayesiano via INLA (Integrated Nested Laplace Approximations) e módulo SPDE (Stochastic Partial Differential Equations), implementados no software R. A qualidade de ajuste e o poder preditivo do modelo foram avaliados mediante DIC (Deviance Information Criterion), WAIC (Watanabe-Akaike Information Criterion) e LCPO (Logarithm Conditional Predictive Ordinate). Foram registradas 16 espécies de elasmobrânquios, cujo número variou de 1 à 9 por lance. No modelo proposto, o efeito espacial e as variáveis ambientais foram relevantes para explicar a variação da riqueza de elasmobrânquios na costa do Rio Grande do Sul. Esta abordagem estatística permite estimar a probabilidade de ocorrência das espécies em áreas não amostradas, levando em conta a autocorrelação espacial dos dados e o conhecimento dos valores das co-variávies ambientais.

We document the expansion of the breeding distribution of the Little Blue Heron Egretta caerulea (Linnaeus, 1758) to 850 km beyond its previous southern limit in South America. In addition we present data on abundance, breeding biology and food of the species in the Patos Lagoon estuary, the area which the species recently colonized. The maximum abundance recorded in the breeding colony and in a nocturnal roosting site was 53 and 49 individuals respectively. Nesting occurred from September to March. Birds nested in a mixed breeding colony together with about 3,000 breeding pairs of seven other species of Pelecaniformes, in a swampy forest near the margin of the estuary. Five nests were between 1.5 and 4.3 m from the ground, on the shrub Daphnopsis racemosa (Thymelaeaceae), on the trees Sebastiana brasiliensis (Euphorbiaceae) and Mimosa bimucronata (Leguminosae), or on the bamboo Bambusa sp. (Poaceae). Four nests produced two fledglings each, while one nest was abandoned. Of 13 grouped samples of food regurgitated by five nestlings, Pink Shrimp Farfantepenaeus paulensis (Perez-Farfante, 1967) constituted 70% in mass, while total length of ingested fishes and shrimps varied mostly between 20 and 50 mm. Estuarine prey items represented 99% of the total food mass. The recent southward expansion of the breeding range of the Little Blue Heron in South America may be a response to climate warming of the Patos Lagoon estuary. Degradation of estuaries in the southwestern Atlantic may also be forcing the birds to breed in areas outside previous geographical range. No presente trabalho é documentada a expansão da distribuição reprodutiva da garça-azul Egretta caerulea (Linnaeus, 1758) 850 km para o sul das colônias mais austrais previamente conhecidas. Adicionalmente, são apresentadas informações sobre abundância, reprodução e alimentação da espécie no estuário da Lagos dos Patos, região recentemente colonizada no extremo sul do Brasil. As garças-azuis nidificaram em uma colônia multiespecífica localizada em uma mata paludosa às margens do estuário, contendo outras sete espécies de Pelecaniformes, totalizando cerca de 3.000 pares reprodutivos. O período reprodutivo se estendeu de setembro até fins de março, e as maiores abundâncias registradas na colônia e no dormitório foram 53 e 49 indivíduos, respectivamente. Foram encontrados cinco ninhos, construídos sobre árvores Sebastiana brasiliensis (Euphorbiaceae) ou Mimosa bimucronata (Leguminosae), arbustos Daphnopsis racemosa (Thymelaeaceae), ou bambus Bambusa sp. (Poaceae), em alturas entre 1,5 e 4,3 m acima do solo. Quatro ninhos produziram dois filhotes cada, e um foi abandonado. Em uma análise preliminar da dieta, baseada em 13 amostras de alimento regurgitado de cinco filhotes, verificou-se que camarões-rosa Farfantepenaeus paulensis (Perez-Farfante, 1967) corresponderam a 70% das presas consumidas, e os itens alimentares de origem estuarina constituíram 99% da biomassa ingerida. Todos os peixes e a maioria dos camarões consumidos possuíam comprimento total entre 20 e 50 mm. A recente expansão da distribuição reprodutiva da garça-azul em direção ao sul pode ter sido favorecida pelo aquecimento climático observado na região do estuário da Lagoa dos Patos, e influenciado pela degradação dos estuários no Atlântico sudoeste nas últimas décadas, levando as aves a colonizarem áreas fora da sua distribuição habitual.

The composition and magnitude of the catches of the life stages of both sexes of the blue shark Prionace glauca were recorded at sea from 2004 to 2006 during seven commercial longline fishing cruises off Southern Brazil between latitudes of 24°S and 38°S and longitudes 29°W and 52°W. P. glauca occurred in all sets and constituted 63% of the pooled catch in numbers. Fork length (FL) ranged from 84 to 262 cm in the males and from 73 to 247 cm in the females. Sea surface temperature ranged from 16.2 to 28.3 °C. The Subtropical Convergence (STC) of the Southwest Atlantic occurred in the sampling area from autumn to spring (June–December). Small juveniles (FL, 70–129 cm) of both sexes were abundant only in the area of the STC. Of the large juveniles (FL, 130–179 cm), males were abundant south of latitude 23°S and females were scarce in the entire study area. Of the small adults (FL, 180–219 cm), males occurred in the entire study area without a seasonal pattern and females were abundant only in the summer (March) north of latitude 26°S. Large adults (FL, 220–262 cm) of both sexes were scarce at all times. In analogy with the spatial distribution of the life stages of P. glauca in other oceans, the distribution patterns of the life stages in the study area justify the hypothesis that the STC comprises a nursery area of P. glauca in the Southwest Atlantic, where small juveniles of both sexes remain until they reach FL of 130 cm. After that stage the large juvenile males disperse northwards, whereas the large juvenile females move to the south of the STC or to the Southeast Atlantic off Africa. The subadult females move northwards in late summer (March) to areas beyond latitude 25°S. Because of the limitations of the fishery-dependent data and patchy coverage of the study area, no definitive conclusions are presented, but the above hypotheses may orient further study of the spatial distribution of the blue shark in the Southwest Atlantic.

Rafinesque, 1810 is the most diverse genus within the Squalomorphii and the Selachii as a whole, with 32 recognized species. These sharks are small to medium-sized, reaching 23 to 75 cm of total length in the adult phase (COMPAGNO, 1984; LAST; STEVENS, 1994). The species are widespread in temperate and tropical waters, have benthopelagic habits and occur mostly at depths of 200 to 2000 m (COMPAGNO, 1984; MUSICK et al., 2004). Four

We studied the diet of Black Skimmers (Rhynchops niger) through analysis of pellets and faeces collected at Patos Lagoon estuary, southern Brazil, where non-breeding birds gather from December to August. We identified 23 prey types from twelve families of fishes, two of crustaceans, and one of squid (N = 1797 prey items). Silversides (Odonthestes argentinensis and Atherinella brasiliensis), anchovies (mainly Lycengraulis grossidens and Engraulis anchoita), and mullets (Mugil spp.) were the main components of the diet, representing 83% of number and 81% of mass of prey. Prey size ranged 9.7-212.1 mm total length and 0.01-78.1 g, with mean at 51.6 mm and 2.81 g. Considering frequency of occurrence and the relative contribution in number and mass, the Argentinean Silverside (O. argentinensis) was the most important prey in three seasons of the year. Anchovies represented 41% of ingested mass in summer. Small-sized mullets represented 30% of prey number; but showed low mass contribution (maximum of 1...

Censuses of six tern species were carried out in the inlet of Lagoa dos Patos, southern Brazil, and on the beaches just north (along 50 km) and south (60 km) from this site. The Common Tern (Sterna hirundo) was the commonest species between October and March, with maximum abundance in January (14,100 individuals). Abundance peak for the South American Tern (Sterna hirundinacea) took place in the austral winter, with maximum values of 1,500 birds. Trudeau’s Tern (Sterna trudeaui) and Amazon Tern (Sterna superciliaris) had similar seasonal patterns occurring during all months, with abundance peak in the non-breeding period, between January and July. The maximum number of Trudeau’s Tern was estimated to be 440 birds in April and 400 in June, and that of Amazon Tern was 210 birds in April and 230 in May. A maximum of 300 Royal Terns (Sterna maxima) were recorded in September, 280 in June and 280 in July, but the species was found in every month. The Cayenne Tern (Sterna eurygnatha) was also found eve...

A total of 459 (245 females, 214 males) Atlantoraja cyclophora was captured by bottom trawl off the coast of Rio Grande do Sul between 30°40′S and 34°30′S during surveys conducted in winter 2001 and summer/autumn 2002 at depths of 100–300 m. Total length at maturity was 52.8 cm for females and 48.5 cm for males. Symmetry and functional parity of the gonads were observed in both sexes, but there was no significant temporal variation in either sex for any of the reproductive parameters studied. Ovulation and egg-deposition were similarly intensive in both seasons. In adult females, there was an ovarian resting period at an individual level, though it was not synchronized at a population level. Distribution of egg-bearing females was not related to depth or species' range.

Billfishes from the Brazilian oceanic northeastern region feed on a large food spectrum composed mainly of epipelagic species of fish and cephalopods, with occasional occurrences of mesopelagic organisms and crustaceans. The oceanic pomfret, Brama brama, and the squid, Ornithoteuthis antillarum, were the main prey items in the diet of the four species, occurring in at least 50% of the stomachs containing food. There was no correlation between body length of prey and predator, or between mass of stomach content and body mass in the individuals from 100 to 330 cm fork length. The feeding of the four species was characterized by constant ingestion of small quantities of food, and constant presence of food in the stomachs, with a predominance of epipelagic organisms of small sizes with an average of 8.0 cm. The reduced stomach size forces the predators to feed constantly on several meals during the day, and consequently provide constant energy for migration.

The wintering diet of Common Terns Sterna hirundo was studied by using 714 pellets collected on roosting sites at the mouth of the Lagoa dos Patos and on adjacent coastal beaches, in Rio Grande do Sul, southern Brazil, from March 1999 to February 2000. A total of 12 340 individual prey items of 35 different food types was found. Fish was the most important food type in the diet, constituting 32% by number and 93% by mass. Insects contributed 67% by number but only 3% by mass. The main food types were sciaenid fishes Paralonchurus brasiliensis, Micropogonias furnieri, Cynoscion guatucupa and Macrodon ancylodon. Several of these are important commercial species; fisheries potentially impact food availability to the terns, and terns may contribute significantly to the natural mortality of these fishes. Clupeiform fishes, the urophycid fish Urophycis brasiliensis and flying ants (Camponotus sp.) were also important. Species composition of the diet (food types), both by number and by mass, differed significantly between months. Prey sizes ranged in length from 12.7 mm to 217.4 mm. The average estimated total length of fish taken was 77.7 mm, but the mean differed significantly among prey species. The importance of demersal sciaenids to the diet of the Common Tern, a surface predator, may be explained by their association with aquatic predators, especially adult Bluefish Pomatomus saltatrix and Striped Weakfish Cynoscion guatucupa, and the Franciscans Dolphin Pontoporia blainvillei, which drive these fish to the surface. The occurrence of flying ants in the diet was related to offshore winds, which carried these insects out to sea. The occasional high availability of insects possibly changed the cost/ benefit relationship of several food types, causing diet changes. The high number of prey species, the temporal variations in the composition of the diet and the wide range of prey sizes are evidence of the high dietary plasticity of the Common Tern, at wintering areas in southern Brazil.

A total of 425 stomachs of night shark (Carcharhinus signatus), and 98 stomachs of scalloped hammerhead shark (Sphyrna lewini), from longline and surface gillneters near seamounts off northeastern Brazil, were analysed between 1992 and 1999. Both predators prey upon reef and benthopelagic fishes, migrant cephalopods and deep water crustaceans, showing similar feeding niches (Schoener Index T=0.75). The great prey richness of the diets may reflect the fact that the marine food web for these species is very extensive in this region. Due to the concentration for feeding of both predators in the seamounts, intense fisheries should be monitored to avoid localised depletions.Um total de 425 estômagos de tubarão-toninha (Carcharhinus signatus) e 98 estômagos de tubarão-martelo-entalhado (Sphyrna lewini), oriundos da pesca de espinhel e pesca com rede de emalhe nas adjacências dos bancos oceânicos do nordeste do Brasil, foi analisado entre 1992 e 1999. Ambas as espécies predam sobre peixes bento-pelágicos e recifais, cefalópodes migradores, e crustáceos de águas profundas, apresentando nichos alimentares similares (Índice de Schoener T=0.75). A alta riqueza de presas nas dietas deve ser um reflexo de que as teias alimentares para estas espécies são consideravelmente longas nessa região. Devido à concentração alimentar de ambos predadores nos bancos oceânicos, a pescaria intensa deve ser monitorada para evitar depleções locais.

For nine days, the number of sally lightfoot crabs (Grapsus grapsus) in a 300 m² area within the brown booby (Sula leucogaster) colony and the activity of each crab were recorded in the morning (5:30-7:30 h), at midday (11:30-13:30 h), and in the afternoon (15:30-17:30 h). The average number of individuals was 80.2 ± 15.5 (59-111) in the morning, 3.1 ± 2.3 (0-7) at midday, and 65.3 ± 15 (49-92) in the afternoon. A total of 1338 activity records were made, with the crabs standing still or walking in 844 records and handling material or feeding in 494 records. In the latter records, 53% of the crabs were handling detritus (pieces of dry bird excrement and sediment), 12.2% were handling feathers, 12.8% were feed- ing on regurgitated fish, 8.9% were feeding on dead Sula leucogaster, 8.1% were feeding on crab, 4.7% were feeding on material adhered to egg shells, and 0.6% were feeding on live nestlings of S. leucogaster. The low frequency of crabs in the colony around noon shows that the crabs avoid insolation, hiding in shady places and tidal pools. In the Sao Pedro and Sao Paulo Archipelago, the presence of S. leucogaster represents an important food source for G. grapsus. This crab plays the role of a cleaner in the S. leucogaster colony, consuming food remains, broken eggs, and dead birds.

Hydrolagus matallanasi sp. nov., the first species of the genus in the southwest Atlantic, is described from 21 specimens collected on the continental slope of southern Brazilian at 416 736 m depth. This new species can be distinguished from its congeners by the following combination of characters: an irregular brown coloration with reticulations and spots over the body; ventral surface whitish, including pectoral bases; proximal margin of the second dorsal fin whitish; tooth plates striped and bicolor, yellowish and gray; length of dorsal fin spine equal to or a slightly longer than head length; pectoral fin notably long, its tip extending beyond posterior margin of pelvic fin base; upper margin of second dorsal fin notably concave at middle region of second dorsal fin base; second dorsal fin with minimum height less than half of its maximum height (located at points anterior and posterior to middle region of fin); eye length slightly smaller than preorbital length. The new species is compared to H. mirabilis, the most similar species from North Atlantic, and H. alberti, which occurs in the western Atlantic.

Made available in DSpace on 2021-07-14T10:31:11Z (GMT). No. of bitstreams: 0 Previous issue date: 2004-09. Added 1 bitstream(s) on 2021-07-14T11:32:00Z : No. of bitstreams: 1 S1679-62252004000300005.pdf: 286852 bytes, checksum: c28627c2ffa973bf6044593ea22014a8 (MD5) Foram capturados 459 exemplares de Atlantoraja cyclophora na costa do Rio Grande do Sul entre as latitudes 30º40'S e 34º30'S, em dois cruzeiros realizados respectivamente no inverno de 2001 e no verão/outono de 2002, com rede de arrasto de fundo, operada entre 100 e 600 m de profundidade. A espécie ocorreu nas profundidades de 100 a 300 m, não havendo diferenças significativas na freqüência de ocorrência nem na abundância (CPUE; kg/hora) entre latitudes, estratos de profundidade em ambas estações do ano. A proporção sexual não foi significativamente diferente de 1:1 em todas as profundidades. Na área estudada a temperatura variou entre 10,0 ºC e 17,6 ºC e a salinidade entre 35,2 e 36,0 ppm. Não houve correlação entre CPUE e profundidade, temperatura e salinidade. O comprimento total médio das fêmeas (53,2 cm) foi significantemente maior que o dos machos (50,9 cm). Não houve diferença no comprimento total médio entre estações do ano, mas sim entre profundidades, sendo significantemente maiores nos estratos de 100 a 200 m. As distribuições de freqüências de comprimento total foram assimétricas, indicando ausência ou escassez de indivíduos juvenis. A total of 459 individuals of Atlantoraja cyclophora were captured along the Rio Grande do Sul coast between latitudes 30º40'S and 34º30'S. Two surveys were performed, in the winter 2001 and in the summer/autumn 2002, using bottom-trawl between the depths of 100 and 600 m. This species occurred between 100 and 300 m deep, without significant differences in the frequency of occurrence and abundance (CPUE; kg/hour) between latitudes, depth and seasons. The sex ratio was not significantly different from 1:1 in all depths. In the study area, temperature ranged between 10.0 ºC and 17.6 ºC and salinity between 35.2 e 36.0 ppm. There was no correlation between CPUE and depth, temperature and salinity. Mean total length of females (53.2 cm) was significantly larger than males (50.9 cm). No differences were detected in mean total length between seasons, but mean total length was significantly larger in depths of 100 m and 200 m. The distribution of the frequencies of total length was asymmetric, indicating rareness or lack of juveniles in the samples. Fundação Universidade Federal do Rio Grande, Departamento de Oceanografia Universidade Estadual Paulista, Instituto de Biociências Universidade Estadual Paulista, Instituto de Biociências

A total of 152 shark specimens of the genus Etmopterus were collected in southern Brazil between Chui (34°20′S) and the Santa Marta Grande Cape (28°30′S). The specimens were caught by bottom-trawl cruises at depths ranging between 100 and 600 m from August to September 2001 and March to April 2002. The species, identified as Etmopterus gracilispinis, E. lucifer and E. bigelowi, occurred only in the south of 31°S at different depth layers. Etmopterus bigelowi occurred in the deep strata from 400–599 m, whereas E. gracilispinis occurred from 300–599 m. Moreover, two sampled E. lucifer males occurred at a depth of 540 m. The hydrographic conditions of temperature and salinity revealed no seasonal differences. The fact that most of the collected specimens were immature is strong evidence of size segregation, suggesting that the adults of these species occur at depths greater than 600 m. Sexual maturity in E. bigelowi occurred at 63–65 cm total length (TL) in females and 60 cm TL in males. All E. gracilispinis specimens were immature. One E. bigelowi female caught in August was pregnant. Birth was confirmed only in March for E. bigelowi and E. gracilispinis with TL at birth of about 17 and 13 cm, respectively.