. Abstract: Fluctuations in the distribution and abundance of demersal fishes collected by otter trawl on the continental shelf of Ubatuba were examined over a two-year sampling period, in an area up to 50 m depth. A total of 111 species were collected. Seasonal and annual fluctuations in species abundance were related to differences in the distribution of Coastal Water and South Atlantic.Ce1ÍtralWater masses. The demersal fish fauna in the area was divided into three ecologically distinct communities: Tropical Sciaenid, Subtropical Sciaenid, and Gerreid-Haemulid. The most important one is the Tropical Sciaenid Community, characterized by Ctenosciaena gracilicirrhus, Paralonchurus brasiliensis, and Cynoscionjamaicensis.. Resumo: A distribuição e a abundância de peixes demersais na plataforma continental de Ubatuba, até 50 m de profundidade, foram examinadas durante dois anos. Foram coletadas 111 espécies. As flutuações sazonais de abundância estiveram relacionadas com a dinâmica das massas d'água. Três comunidades ocupam a área: Sciaenidae Tropical, Sciaenidae Subtropical e Gerreidae-Haemulidae, sendo a primeira a mais importante, dominada por Ctenosciaena gracilicirrhus, Paralonchurus brasi/iensis e Cynoscionjamaicensis.

Com o objetivo de detectar grupos tróficos, foram analisadas amostras de conteúdos estomacais de sete espécies de peixes cartilaginosos. Os exemplares foram coletados no período de Outubro/85 a Julho/87 na plataforma interna de Ubatuba, SP, Brasil (da costa, até a isóbata de 50 m). A importância dos itens alimentares foi analisada através da freqüência numérica (FN) e da freqüência de ocorrência (FO). As espécies foram agrupadas em três grupos distintos: Piscívoros: Squalus cubensis; comedores de peixes e crustáceos bentônicos: Raja castelnaui, Raja cyclophora, Raja agassizi; comedores de invertebrados bentônicos: Psammobatis glansdissimilis, Rhinobatos horkelii, Zapteryx brevirostris.

The demersal fish community of the Channel and shelf of São Sebastião (SP), on the southeastern Brazilian coast, was investigated during the summer of 1994. The sampling was carried out usinga bottom otter trawl at 26 stations located between 8 m and 65 m in depth. Ninety-three species of 40 families were identified in the area. Sciaenids were the most prominent in number of species, abundance, and weight. Ctenosciaena gracilicirrhus, Paralonchurus, brasiliensis, and Cynoscion jamaicensis dominated in the catches. Cluster analysis showed three major groups of species and three groups of sites. The first group was composed of species found in the Channel and shallower areas of the inner shelf, the second of species associated with the inner shelf «50 m depth), and the third group of species fTom the outer shelf (> 50 m depth). Environrnental variables considered in Canonical Correspondence Analysis (CCA) explained 51 % of the variation in the species data. Bottom water temperature was the most important variable selected by CCA, accounting for 21% of the explainable variance. The results revealed that structure of the ichthyofauna was associated with water mass distribution. During the period studied, the area was occupied by the warm Coastal Water (CW), but cold South Atlantic Central Water (SACW) was detected over the bottom or the outer shelf, influencing the distribution and abundance ofthe main species.
A comunidade de peixes demersais do canal e plataforma de São Sebastião (SP), costa sudeste do Brasil, foi investigada no verão de 1994. A amostragem foi realizada com rede de arrasto de fundo, em 26 estações localizadas entre 8 t' 65 m de profundidade. Foram identificadas 93 espécies pertencentes a 40 famílias. Os cienídeos foram os mais representativos em número de espécies, abundância e peso, sendo Ctenosciaena gracilicirrhus, Paralonchurus brasiliensis e Cynoscion jamaicensis as espécies dominantes. A análise de agrupamento revelou três grandes grupos de espécies e três grupos de estações. O primeiro grupo caracterizou-se pela presença de espécies com ocorrência no canal e regiões costeiras da plataforma interna; o segundo por espécies associadas à plataforma interna >50 m de profundidade) e o terceiro grupo por espécies relacionadas à plataforma externa (>50 m). As variáveis ambientais selecionadas pela CCA explicaram 51 % da variação dos dados das espécies, sendo a temperatura da água de fundo a mais importante, representando 21% da variância. Verificou-se a importância da distribuição das massas d'água na estruturação da comunidade de peixes demersais. Durante o período de amostragem a área foi ocupada pela massa d'água quente da Água Costeira (AC). No entanto, a presença da Água Central do Atlântico Sul (ACAS), mais fria, foi detectada na camada de fundo da plataforma externa, influenciando a distribuição e abundância das espécies dominantes

SYNOPSISThis paper analyses some aspects on the length/weight relationship of Sardinella brasiliensis and its variations as a function of their reproductive cycle and displacements along the Brazilian coast between 23 0 S and 28°S. The area surveyed was divided into five subareas, each one covering one degree of latitude. The relationship and its variations between shoals were studied for each sub-area at different seasons and for the sub-are as at the same season. The absence of a variation pattern for the length/weight relationship has shown to be the result of seasonal changes in the physiological aspects of fish (as a function of their reproductive cycle) as well as result of behaviour of individuaIs in two main areas: 23 0 S-25 0 S and 26 0 S-28 0 S, which are spawning areas, spawning occuring during spring and summer at the first and only during spring at the latter. After spawning the young (from both areas) more at different times to a common trophic area where they find suitable conditions (25 0 S-26°S), returning to their original sub-areas at different occasions, following their first sexual maturation. Although spawning takes place at different times and sites, with the convergence of young to a common nursery, mixing might occur. Further studies on meristics and body proportions are being developed regarding the existence of different populations.

Planktonic and benthic productivity and consumption were estimated to assess the availability of food to higher trophic-level consumers in the Ubatuba ecosystem on the SE coast of Brazil. The study area included waters from 10 to 100 m deep and covered 3800 km 2. The trophic compartments of the system were established on ecologically or taxonomically related species, considering their relative abundance and similarity of diets and habits. The compartments are phytoplankton, zooplankton, salps, bacterioplankton, cnidaria, polyplacophora, mollusca, carnivorous benthos, detritivorous polychaetes, other detritivorous benthos, penaeidea-caridea, brachyura, and echinodermata. Biomass, production, and consumption were estimated in summer and winter. Plankton biomass, production and consumption were higher in summer than in winter, mainly because of the presence of salps. Primary production was estimated as 1486 g wet weight m-2 3 months-1 in summer and 704 g in winter. Total benthic biomass in summer (101 gww m-2) was twice that in winter (53 gww m-2), but its production and consumption were similar in both seasons.

In the southeastern coast of Brazil, catches of the Brazilian sardine (Sardinella brasiliensis) have been decreasing from more than 200 thousand tons/year in the early '70s to about 32 thousand tons in 1990. From 1994 to 1997, catches recovered slightly (118 thousand tons), dropping then to about 20 thousand tons in 1999-2000. Extensive investigations on biology and stock assessment of Brazilian sardine have been developed in the '80s, providing stock biomass and recruitment estimates based on commercial fishing data obtained from 1977-1992. The present paper aims to update biological and stock assessment parameters from sardine data obtained during two acoustic surveys carried out in 1995 and commercial catches from the 1993-1997 period. Results from both cruises showed the weight-length relationship Wt=0.0000019. Lt3,26 (90-240 mm total length) and four age classes (mostly class II+). In the commercial catches, sardines belonged to ages 0+ and 3+ years old (mostly older than 1-year old) with 90-250 mm total length. Annual growth parameters were: Li=275 mm, K= 0.55 (1996), and Li=273 mm, K=0.50 (1997). Total mortality (Z) and natural mortality (M) coefficients were: Z= 3.8; M= 0.7 -1.2 (1996), and Z= 3.6; M= 0.6 - 1.1 (1997). The variation amplitude of M is due to the application of several different methods. Considering the historical series of 21 years of data (1977-1997), results showed that the stock went through two favorable periods (1980-84, 1989-94) and one unfavorable period (1985-89). 1997 seems to have been the beginning of a new unfavorable period, revealing recruitment cycles likewise other stocks from California and Japan.

In the southeastern coast of Brazil, catches of the Brazilian sardine (Sardinella brasiliensis) have been decreasing from more than 200 thousand tons/year in the early '70s to about 32 thousand tons in 1990. From 1994 to 1997, catches recovered slightly (118 thousand tons), dropping then to about 20 thousand tons in 1999-2000. Extensive investigations on biology and stock assessment of Brazilian sardine have been developed in the '80s, providing stock biomass and recruitment estimates based on commercial fishing data obtained from 1977-1992. The present paper aims to update biological and stock assessment parameters from sardine data obtained during two acoustic surveys carried out in 1995 and commercial catches from the 1993-1997 period. Results from both cruises showed the weight-length relationship Wt=0.0000019. Lt3,26 (90-240 mm total length) and four age classes (mostly class II+). In the commercial catches, sardines belonged to ages 0+ and 3+ years old (mostly older than 1-year old) with 90-250 mm total length. Annual growth parameters were: Li=275 mm, K= 0.55 (1996), and Li=273 mm, K=0.50 (1997). Total mortality (Z) and natural mortality (M) coefficients were: Z= 3.8; M= 0.7 -1.2 (1996), and Z= 3.6; M= 0.6 - 1.1 (1997). The variation amplitude of M is due to the application of several different methods. Considering the historical series of 21 years of data (1977-1997), results showed that the stock went through two favorable periods (1980-84, 1989-94) and one unfavorable period (1985-89). 1997 seems to have been the beginning of a new unfavorable period, revealing recruitment cycles likewise other stocks from California and Japan.
Na costa sudeste do Brasil, as capturas da sardinha-verdadeira {Sardinella brasliensis) decresceram de mais de 200 mil t/ano no início dos anos 70 para cerca de 32 mil t em 1990. De 1994 a 1997, as capturas se recuperaram alcançando 118 mil t, caindo então para cerca de 20 mil t em 1999-2000. Estudos abrangentes sobre a biologia e avaliação do estoque da espécie foram desenvolvidos nos anos 80, permitindo a estimativa da biomassa e recrutamento do estoque com base em dados da pesca comercial durante 1977-1992. Os objetivos do presente trabalho foram atualizar as estimativas dos parâmetros biológicos e avaliação do estoque através de dados obtidos durante dois cruzeiros de prospecção acústica realizados em 1995 e de dados da captura comercial no período 1993-1997. Como resultados de ambos os cruzeiros, a relação peso/comprimento estimada foi: Wt=0,0000019.Lt'~6 (amplitude de comprimento total de 90-250mm) e quatro classes etárias (maior freqüência para a classe II+) estiveram presentes. Nas capturas da pesca comercial ocorreram indivíduos de idades 0+ a Ill+ anos, principalmente adultos com mais de 1 ano de idade e comprimentos entre 90-250mm. Os valores dos parâmetros de crescimento estimados foram Li = 275 mm e K = 0,55 (1996), e Li = 273 mm e K = 0,50 (1997). As taxas de mortalidade total (Z) e natural (M) foram: Z = 3,8 e M = 0,7 - 1,2 (1996), e Z = 3,6 e M = 0,6 - 1,1 (199...

Biological data, size frequency distribution of intraovarian oocytes, maturity indices and histological observations of the gonads were used to assess the spawning cycle of S. brasiliensis. sampled September 1981-August 1982 throughout the main fishing area off the Brazilian coast ( 2 2 3 to 28"s). Post-ovulatory follicles are described and classified, and the incidence of mature females displaying these structures was calculated. The main findings were (a) spawning occurred during the spring and summer with a maximum in December and January; (b) spawning occurred throughout the area studied; (c) spawning was fractional; (d) average batch fecundity was 26 OOO oocytes per female, or 393 eggs g-'; (e) spawning frequency reached values of approximately 50% during the spawning peak, but was sensibly lower during the other months of spawning activity.