Reproductive Biology and Recruitment of Xiphopenaeus kroyeri in a Marine Protected Area in the Western Atlantic: Implications for Resource Management

The potential of a recently established marine protected area (MPA) in the Western Atlantic, Brazil, as a \u27seed production\u27 and nursery ground for Xiphopenaeus kroyeri, an intensively exploited penaeid shrimp, was investigated in an attempt to reveal any future benefit of this new MPA to adjacent populations experiencing heavy exploitation. Overall, we observed that males and females \u3e12 and 20 mm carapace length, respectively, contributed the most to reproduction in the studied population. Reproductive activity of X. kroyeri was continuous at the MPA; 2 annual reproductive peaks were recorded from March to April and from November to December, which were followed by recruitment events occurring from March to April 2009 and November 2009. Sediment, temperature, and algae and plant biomass floating near the bottom were relevant in driving reproductive activity and recruitment in X. kroyeri. The high reproductive potential of the studied population and the occurrence of abundant juveniles throughout the sampling area, indicating the existence of a nursery ground within the region, suggest that this MPA might provide important benefits in the near future. We argue in favor of future long-term studies on the larval dispersion, reproductive biology and ecology of X. kroyeri in MPAs and non-MPAs to construct a base for future management of this species and to aid stock recovery in fishing areas that are heavily exploited

Ecological distribution and population structure of Acantholobulus schmitti (Rathbun, 1930) (Crustacea, Decapoda, Xanthoidea) on the southeastern Brazilian coast

Os objetivos deste estudo foram analisar a distribuição ecológica e a estrutura populacional de A. schmitti no litoral sudeste brasileiro. Os caranguejos foram coletados, mensalmente, de janeiro de 1998 a dezembro de 1999 nas enseadas: Ubatumirim (UBM), Ubatuba (UBA) e Mar Virado (MV), onde também foram obtidas amostras de água e sedimento para análise dos fatores ambientais. A maior abundância de A. schmitti foi verificada em UBM (224), seguida por UBA (154) e MV (23) e não apresentou associação com os fatores ambientais analisados. O motivo da baixa abundância desses caranguejos em MV pode ser a alta ação de ondas que movimenta o material biodetrítico acumulado no fundo e, frequentemente, remove pequenos caranguejos de seus abrigos entre fragmentos de conchas. Os indivíduos foram 269 machos e 132 fêmeas, das quais apenas 4 eram ovígeras. O recrutamento juvenil ocorreu o ano todo, sendo menos intenso na primavera. A maior abundância de indivíduos, bem como as fêmeas ovígeras, ocorreu em 1999, quando a entrada da Água Central do Atlântico Sul (ACAS) foi mais intensa do que no ano anterior. Esta influência ambiental pode ser o principal fator modulador para esta população.This investigation analyzed the ecological distribution and population structure of A. schmitti on the southeastern coast of Brazil. Crabs were sampled monthly from January 1998 to December 1999 at the following bays: Ubatumirim (UBM), Ubatuba (UBA) and Mar Virado (MV). Water and sediment samples were also collected from all sampling sites for an analysis of environmental factors. Acantholobus schmitti was most abundant at UBM (224), followed by UBA (154) and MV (23) but its abundance showed no association with the environmental factors analyzed. The low abundance of these crabs in MV may be due to the high wave action that moved biodetritic material accumulated on the bottom and frequently removed small crabs from their sheltered positions among the shell fragments. The individuals captured included 269 males and 132 females, of which only 4 specimens were brooding females. Juvenile recruitment occurred throughout the year, but was less intense in the spring. The major abundance of individuals as well as of ovigerous females occurred during 1999, when the entrance of the South Atlantic Central Waters (SACW) was stronger than in previous year. This environmental influence could be the main factor modulating this population

Assembleia de ermitões nas proximidades de ilhas costeiras do sudeste do Brasil

An assortment of environmental factors may limit the permanence of hermit crabs in the environment, and determination of certain ecological indices can reveal the current conditions of the assemblage. This study evaluated the assemblage of hermit crabs near two islands adjacent to areas with fishing activity. Hermit crabs were collected monthly near Couves and Mar Virado islands on the southeastern coast of Brazil, from January through December 1998. Environmental factors were also recorded monthly. Ecological indices including species richness, diversity, evenness and dominance were calculated. The environmental characteristics differed between the islands, which helps to explain the differences in the composition of hermit crabs between the locations. Hermit crabs were significantly more abundant near Couves Island, where, according to the canonical correspondence analysis (CCA), the environmental parameters varied less. The Monte Carlo test (P < 0.05) confirmed the CCA model, indicating a strong correlation between the species of hermit crabs, bottom and surface water temperatures, and sediment organic-matter content. The presence of ovigerous females throughout the year indicates that these areas are favorable for reproduction. These results indicate that the environmental heterogeneity allows the establishment of different species of hermit crabs, influencing species richness and abundance of individuals in the ecosystem. These conditions favor the establishment of diverse benthic communities near the studied islands.Keywords: Diogenidae, Paguridae, diversity, abundance, multivariate analysis, Dardanus insignis, Loxopagurus loxochelis.Uma variedade de fatores ambientais pode limitar a permanência de ermitões no ambiente, sendo que alguns índices ecológicos podem revelar as condições da assembleia. Este trabalho avalia a assembleia de ermitões em duas ilhas adjacentes a regiões com atividade pesqueira. Os ermitões foram coletados mensalmente nas ilhas das Couves e do Mar Virado, pertencentes ao litoral sudeste brasileiro, no período de janeiro a dezembro de 1998. Fatores ambientais também foram registrados mensalmente. Índices ecológicos como riqueza, diversidade, equidade e dominância foram calculados. As características ambientais foram diferentes entre as ilhas, o que pode explicar as diferenças na composição de espécies entre os locais. A abundância de indivíduos foi significativamente maior na ilha das Couves, a qual apresenta, segundo a análise de correspondência canônica (CCA), menores oscilações em suas variáveis ambientais. O teste de Monte Carlo (P < 0.05) confirmou a robustez da CCA, evidenciando uma forte correspondência entre as espécies de ermitões, temperatura de fundo e superfície e teor de matéria orgânica. A presença de fêmeas ovígeras ao longo do ano também aponta as áreas como propícias à reprodução. Desta maneira, os resultados permitem concluir que a heterogeneidade dos ambientes permite o estabelecimento de diferentes espécies de ermitões, influenciando a riqueza de espécies e a abundância de indivíduos no ecossistema local. Tal condição propicia o estabelecimento de comunidades bentônicas distintas nas ilhas estudadas.Palavras-chave: Diogenidae, Paguridae, diversidade, abundância, análise multivariada, Dardanus insignis, Loxopagurus loxochelis

Arquitetura Corpórea e Padrões de Desenvolvimento dos Metazoários

Os objetivos da Zoologia são, basicamente, a detecção dos problemas da existência animal e das soluções desenvolvidas durante a evolução. Os obstáculos que os organismos enfrentam são de várias naturezas, mas relacionam-se, principalmente, com as condições físicas, químicas e bióticas em que vivem, as quais podem ser constantes, ou não, ao longo do tempo. Desse modo, a diversidade animal reflete as adaptações morfo-funcionais e comportamentais que os organismos desenvolveram frente às condições ambientais em que vivem. Os animais encontraram inúmeras possibilidades de forma de vida para habitar os diversos ecossistemas da Terra. O Brasil apresenta uma fauna diversa, graças à sua grande extensão territorial e localização, que abrange ecossistemas terrestres, de água doce, marino e suas interfaces.Fil: Delevati Colpo, Karine. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Limnología "Dr. Raúl A. Ringuelet". Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Instituto de Limnología; ArgentinaFil: Fransozo, Vivian. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi

Juvenile development of Callinectes danae Smith, 1869 ( Crustacea, Decapoda, Brachyura, Portunidae) under laboratory conditions

The juvenile development of Callinectes danae was investigated from megalopae obtained in neuston samples at Ubatuba, Sao Paulo, Brazil. The individuals were raised in the laboratory under constant temperature ( 25 +/- 1 C), filtered sea water from the collection location (35%), and natural photoperiod. Newly hatched Artemia sp. nauplii were offered as food on a daily basis and ornamental-fish food was also provided for the juveniles from the 4(th) stage on. Twelve stages of the juvenile phase were obtained. The main morphological features that allowed recognition of the first juvenile stage were drawn and described. All the subsequent stages obtained were examined and measured, and the main changes in relation to the first stage were recorded. Sexual dimorphism becomes apparent from the fourth juvenile stage onwards. Some appendages and morphological features proved to be of great importance in the identification of species, including the number of segments of the antennal flagellum and the number of setae on the maxilla and on the 1(st), 2(nd) and 3(rd) maxillipeds. These can probably be used for future comparisons and species identifications.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Reproductive period and size at the onset of sexual maturity of mottled purse crab, Persephona mediterranea (Herbst, 1794) (Brachyura, Leucosioidea) on the southeastern Brazilian coast

The reproductive biology of Persephona mediterranea was investigated in relation to the following aspects: population structure, size at the onset of sexual maturity, sexual size dimorphism, and reproductive period. A total of 1,283 specimens were obtained (565 males, 120 non-ovigerous females and 598 ovigerous females). CW(50) values were 22.8 and 22.3 mm CW for males and females, respectively, and the mean size of males was significantly larger than that of females. Persephona mediterranea shows continuous reproduction. However, there is a reduction M the proportion of ovigerous females and males with gonads in advanced developmental stage during the autumn and beginning of the winter. There was no significant correlation between the reproductive activity and variation in abiotic factors. of the total captured specimens, 98.99% were sexually mature, which may indicate a differential spatial distribution among the distinct age groups, and sampling sites are probably areas occupied by adult individuals or this population.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Reproductive cycle and ovarian development of the marine ornamental shrimp Stenopus hispidus in captivity

The reproductive cycle and ovarian development of the marine ornamental shrimp Stenopus hispidus were described starting from adult mating pairs under laboratorial conditions. The pairs were individually kept in aquaria under constant conditions of salinity (35‰), temperature (26± 0.5 °C) and photoperiod (12L:12D). Molting, mating, spawning and hatching were recorded during three consecutive reproductive cycles. Females at different stages of ovarian development were anesthetized and their ovaries were removed, photographed, fixed and processed for histological examination. Mating occurred after female molting. Mean incubation time was 22.8± 2.1 days and mean intermolt periods were 25.5± 2.3 days for females and 26± 4.1 days for males. The ovaries varied in size and color during each reproductive cycle, which could be clearly seen through the transparent carapace. Spent ovary (translucent), lasted for 3 days after egg spawning; developing ovary (white), lasted 7 days; developed ovary (light green), between 5 and 8 days and advanced ovary (dark green) lasts 10 to 13 days. Microscopically, the ovarian stages differed in proportion of follicular cells, oocytes and oogonia. Follicular cells were abundant and mature oocytes were absent at the spent stage, while the number and size of secondary oocytes increased gradually thereafter. The present study indicates that S. hispidus can undergo multiple reproductive cycles under culture conditions. The changes in the macroscopic appearance of the ovary are strongly associated with the reproductive cycle.Fil: Gregati, Rafael A.. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Fransozo, Vivian. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Lopez, Laura Susana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Negreiros Fransozo, María Lucía. Universidade Estadual Paulista Julio de Mesquita Filho; Brasi

Reproductive biology and recruitment of Xiphopenaeus kroyeri in a marine protected area in the Western Atlantic: implications for resource management

The potential of a recently established marine protected area (MPA) in the Western Atlantic, Brazil, as a 'seed production' and nursery ground for Xiphopenaeus kroyeri, an intensively exploited penaeid shrimp, was investigated in an attempt to reveal any future benefit of this new MPA to adjacent populations experiencing heavy exploitation. Overall, we observed that males and females >12 and 20 mm carapace length, respectively, contributed the most to reproduction in the studied population. Reproductive activity of X. kroyeri was continuous at the MPA; 2 annual reproductive peaks were recorded from March to April and from November to December, which were followed by recruitment events occurring from March to April 2009 and November 2009. Sediment, temperature, and algae and plant biomass floating near the bottom were relevant in driving reproductive activity and recruitment in X. kroyeri. The high reproductive potential of the studied population and the occurrence of abundant juveniles throughout the sampling area, indicating the existence of a nursery ground within the region, suggest that this MPA might provide important benefits in the near future. We argue in favor of future long-term studies on the larval dispersion, reproductive biology and ecology of X. kroyeri in MPAs and non-MPAs to construct a base for future management of this species and to aid stock recovery in fishing areas that are heavily exploited.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq