Sistemática de Solução de Controvérsias do Mercosul: o Protocolo de Brasília e o Protocolo de Olivos

O sistema originário de soluções de controvérsias no Mercosul era retratado pelo Protocolo de Brasília (PB) e pelo Protocolo de Ouro Preto (POP). Em 2002, o PB foi derrogado expressamente pelo Protocolo de Olivos (PO) para a solução de controvérsias no Mercosul. O novo sistema de solução de controvérsias do PO apresenta avanços significativos em relação à sistemática anterior

Population biology of Ampithoidae species (Crustacea, Amphipoda) associated with Sargassum filipendula (Phaeophyta, Fucales), at Fortaleza beach, Ubatuba, São Paulo, Brazil

The population biology of three species of the family Ampithoidae (Ampithoe ramondi, Cymadusa filosa e Sunampithoe pelagica) associated with Sargassum filipendula at Fortaleza beach, northern coast of São Paulo state was investigated from June 2000 to May 2001. The amphipods were identified, counted and separated in size classes through a nested sieve set. Month hystograms were obtained for juveniles, males and females. The ampithoid sex ratio was determined monthly. The reproductive biology of the species was evaluated by the relative frequency of ovigerous females, fecundity, average egg volume and correlation analysis between head lengh of ovigerous females and number of eggs in its brood pouch. Ampithoe ramondi was the most abundant species. The higher densities of the three species occurred in spring and summer. The sex ratio presented a significant difference from 1:1 only for A. ramondi (1:1.2; x² = 4.37; g.l. = 1; p < 0.05). Ovigerous females were registered for almost all the sampling periods. A positive correlation between the female head lengh and the number of eggs were only registered for A. ramondi (r&sup2; = 0.27; p < 0.05; n = 33). Cymadusa filosa showed the greatest fecundity and egg volume.A biologia populacional de três espécies de anfípodes da família Ampithoidae (Ampithoe ramondi, Cymadusa filosa e Sunampithoe pelagica) associadas a Sargassum filipendula da Praia da Fortaleza, litoral norte do Estado de São Paulo foi estudada entre junho de 2000 e maio de 2001. Os anfípodes foram identificados, contados e separados em classes de tamanho através de um conjunto de peneiras agrupadas. Foram obtidos histogramas mensais de jovens, machos e fêmeas. A razão sexual dos ampitoídeos foi avaliada mensalmente. A biologia reprodutiva das espécies foi avaliada através freqüência relativa mensal de fêmeas ovígeras, de sua fecundidade, volume médio dos ovos e correlação do tamanho da cabeça com o número de ovos contidos em seus marsúpios. Ampithoe ramondi foi a espécie mais abundante. As maiores densidades para as três espécies ocorreram na primavera e no verão. A razão sexual apresentou diferença significativa de 1:1 apenas para A. ramondi (1:1,2; x² = 4,37; g.l. = 1; p < 0,05). Fêmeas ovígeras foram registradas em quase todos os períodos de amostragem. Correlação positiva baixa entre o tamanho da cabeça da fêmea e o número de ovos contidos na bolsa incubadora foi registrada somente para A. ramondi (r&sup2; = 0,27; p < 0,05; n = 33). Cymadusa filosa apresentou a maior fecundidade e o maior volume dos ovos.12071216Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Temporal variation of epi- and endofaunal assemblages associated with the red sponge Tedania ignis on a rocky shore (São Sebastião Channel), SE Brazil

ABSTRACT Sponges are biogenic substrates that increase the available space on rocky shores and provide shelter for many groups of the benthic fauna, which can live both inside and on these sessile invertebrates. In order to assess the differences in temporal variation of endobiont and epibiont groups, samples of the red sponge Tedania ignis (Duchassaing & Michelotti, 1864) were obtained each month for one year. The density, richness and diversity of endobiont and epibiont groups were analyzed in relation to abiotic factors. The dry mass of the sponge was negatively correlated with the density of individuals in both groups and positively with the diversity of endobionts, while organic matter was positively correlated with the diversity of epibionts. Endobiont diversity was more highly correlated with intrinsic factors of the sponge, whereas the diversity of epibionts was more highly correlated with factors related to the surrounding environment

Hermit crab (Decapoda, Anomura) attraction to dead gastropod baits in an infralittoral algae bank

Hermit crabs use gastropod shells as shelter and are adapted to follow chemical cues released from tissues of dead or injured gastropods as a way to find new and more adequate shells. The species composition, crab size, shell types adequacy and physical condition were compared between attracted individuals and crabs collected in previous samples. The previous sampling was carried out in five areas before each experiment. Then, five baits of crushed gastropods in nylon net bags were installed in these areas. Three samples were taken at 30min intervals, capturing all crabs within a circle of 60cm diameter. Attraction of hermit crabs was tested for four different gastropod baits to verify specificity of the chemical cues. Clibanarius antillensis, Pagurus brevidactylus and Paguristes tortugae were collected in the study area. Pagurus brevidactylus, the smallest species, turned out to be more attracted than the 2 other species. The results showed that attracted crabs utilized more gastropod shell types than that collected in previous samples, however shell utilization pattern did not differ between them. Attracted animals were slightly smaller (shield length) than those collected in the previous samples but did not present significant differences in shell adequacy and condition. The four experimental baits attracted the crabs in similar ways not indicating a specific response from the crabs. The fact that attracted animals were smaller suggested that the attraction to dead gastropods might enable the acquisition of a new and larger shell and, consequently, chains of shell exchange between the attracted crabs.<br>Ermitões utilizam conchas de gastrópodes para abrigo. Conchas novas e mais adequadas podem ser encontradas pelos ermitões pois estes são atraídos por substâncias químicas liberadas pelos tecidos de gastrópodes feridos ou mortos. A adequação, condição e tipo das conchas e a composição de espécies e o tamanho dos ermitões foram comparados entre indivíduos atraídos e os coletados em amostras prévias. Estes últimos ermitões foram coletados em 5 áreas antes de cada experimento. Nestes experimentos, sacos de tela de nylon contendo um gastrópode amassado foram colocadas nas áreas de atração. Foram obtidas 3 amostras por área em intervalos de 30 minutos, coletando-se todos os ermitões dentro de um raio de 30cm em volta da isca. Foi testada a atração a iscas de 4 espécies de gastrópodes para observar a possibilidade de especificidade ao sinal químico. Clibanarius antillensis, Pagurus brevidactylus e Paguristes tortugae foram coletados na área de estudo. Pagurus brevidactylus, a menor espécie, mostrou ser mais atraída do que as outras duas espécies. Verificou-se que os ermitões atraídos utilizaram maior número de tipos de conchas do que os coletados nas amostras prévias, contudo o padrão de utilização de conchas não diferiu. Os ermitões atraídos foram ligeiramente menores (comprimento do escudo cefalotorácico) do que os coletados nas amostras prévias mas não mostraram diferenças significativas na condição e adequação das conchas. Os 4 experimentos utilizando diferentes iscas atraíram os ermitões de forma semelhante não havendo indicação de resposta específica. O fato dos ermitões atraídos serem menores que os das amostras prévias sugere que a atração aos gastrópodes mortos pode possibilitar a aquisição de conchas novas e maiores e, conseqüentemente, a ocorrência de uma cadeia de trocas de conchas entre os ermitões atraído

Testing the importance of predation refuge vs. food quality in determining the use of macroalgal hosts by a generalist marine mesograzer

Bottom-up (e.g. resource quality) and top-down (e.g. predation) factors have strong effects on the fitness and distribution of small herbivores. Herein, we investigated how food quality and refuge offered by macroalgal hosts influence the distribution of a mesograzer. We used the herbivorous amphipod Cymadusa filosa and seasonally evaluated its association with the macroalgal hosts Sargassum filipendula, Padina gymnospora, and Dichotomaria marginata on a subtropical rocky shore from the Brazilian southeastern coast. Feeding experiments were conducted to test the food value of hosts, while predation experiments in the field and laboratory were performed to investigate the refuge value of the macroalgae. Cymadusa occurred on Padina in a density greater than that observed on Dichotomaria and Sargassum, while Dichotomaria harbored more amphipods than Sargassum. Adults of Cymadusa showed a higher consumption of Padina and Sargassum in both choice and no-choice feeding experiments and juveniles had greater growth and reproductive potential when feeding on such macroalgae. In the predation experiment in the field, Padina was a better refuge for Cymadusa than Sargassum. However, no difference in refuge value among hosts was observed in the laboratory assays. The distribution of Cymadusa was explained by a balance between food and refuge values of hosts, with higher abundances being observed in the high-quality food alga that provides refuge against predators (e.g. Padina), while fewer individuals occurred in other high-quality food that was less suitable as refuge (e.g. Sargassum). Therefore, predation may be more of a determinant for distribution of that mesograzer than resource quality1665FAPESP – Fundação de Amparo à Pesquisa Do Estado De São Paulo2013/17629-