Oyster culture has a potential to generate income for coastal communities and to lessen pressure on natural overexploited populations. A project to transfer mangrove oyster Crassostrea rhizophorae raft culture technology to selected coastal communities in Margarita Island, Venezuela is being developed, and an optimum location selection technique was devised. To pick the variables or factors that determine site suitability, a bibliographic database was made, aspects of interest chosen, and the most comprehensive ones singled out, eliminating redundant ones. Twenty variables were grouped in criteria based on the way they influence the project. Variables were classified as intrinsic environmental, environmental extrinsic, logistic, and socioeconomic criteria. Thirty-five experts were asked to evaluate the factors and to score each according to their suitability weight. Logistic criterion received the highest values, followed by environmental extrinsic issues. A Geographic Information System using a base map compiled from 1:25,000 scale maps was developed. A thematic map for each factor was completed, dividing graphically the 3896-km2 study area into polygons of equal weight for each factor. The Multi-Criteria Evaluation (MCE) was used to combine the variables. Resultant vectors in thematic maps were added to obtain smaller polygons with the same value sum. Finally, MCE was used to generate a final output: the optimum sites for oyster aquaculture resulting from the added values of over 3000 polygons in the maps, for the 20 criteria. Higher scores were reached in 13 areas covering 4.1 km2, those places having the optimum conditions for oyster raft aquaculture in the region. Additional locations meeting 75% to 70% of the demanded criteria for a final suitable selection cover 137 sites encompassing 37.5 km2.

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The aim of the present study was to evaluate the potential use of otolith microchemistry (Sr:Ca and Ba:Ca ratios) to identify silver mullet, Mugil curema, populations in Southeastern Caribbean Sea. Fish samples were collected in 7 areas of Nueva Esparta State (Venezuela). The otolith Sr:Ca and Ba:Ca ratios and water Sr:Ca were determined (by ICP-OES and EDTA volumetric method). Otoliths Sr:Ca and Ba:Ca ratios and Sr:Ca partition coefficient of mullets in Cubagua island (south of the State) were significantly different from ratios in La Guardia (north of the State). A discriminant analysis of otolith Sr:Ca and Ba:Ca ratios separated Cubagua Island from La Guardia values. These results suggest the existence of different mullet groups in the Southeastern Caribbean Sea. For this, the simultaneous use of Sr:Ca and Ba:Ca ratios could be a potential tool to identify populations in the study area.Keywords: Mugilidae, fish resource, otolith, microchemistry. A microquímica do otólito é um indicador do habitat de Mugil curema no sudeste do Mar Caribenho?Resumo O objetivo do presente estudo foi avaliar o potencial uso da microquímica do otólito (razões Sr:Ca e Ba:Ca) para identificar distintas populações de tainha, Mugil curema, no sudeste do mar caribenho. Os peixes foram coletados em 7 áreas do estado de Nueva Esparta (Venezuela). As razões Sr:Ca e Ba:Ca do otólito e a razão Sr:Ca da água foram determinadas (pelo ICP-OES e EDTA método volumétrico). As razões de Sr:Ca e Ba:Ca dos otólitos e o coeficiente de partição das tainhas da Ilha Cubagua (sul do estado) foram significativamente diferentes das razões de La Guardia (norte do estado). A análise discriminante das razões de Sr:Ca e Ba:Ca dos otólitos separa os valores da Ilha Cubagua e de La Guardia. Estes resultados sugerem a existência de diferentes grupos de Mugil curema no sudeste do mar Caribenho e que o uso simultâneo das razões Sr:Ca e Ba:Ca poderiam ser uma potencial ferramenta para identificar as populações da área de estudo.Palavras-chave: Mugilidae, recurso pesqueiro, otólito, microquímica.

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Capture-mark-recapture data, individual morphometrics (including size and growth), remigration data, and nesting population size (2000-2006) are presented for leatherback sea turtles (Dermochelys coriacea) in Cipara and Querepare, Paria Peninsula, Venezuela. From 502 tagged females, the average remigration interval for 41 individuals seen in subsequent years was 2.5 years. In Querepare, remigrants (previously tagged) and neophytes (untagged individuals) increased significantly; in Cipara, remigrants increased significantly but neophytes did not. Of 38 tagged females observed nesting at more than one beach during a nesting season, 73.6 % traveled between Cipara and Querepare (30 km) and 10.5 % the balance between Cipara or Querepare and Unare (10-30 km) and 7.9 % between Paria and Margarita Island (130 km), as well as 5.3 % internationally between Paria and Trinidad (240 km) and 2.6 % between Cipara and Dominica (550 km). Mean curved carapace length (CCL) and width (CCW) of 403 measured females was 151.78±6.20 cm and 110.03±4.42 cm, respectively. Of 46 nesting females measured during more than one reproductive season, mean growth in CCL and CCW was 0.85±1.10 cm*yr–1 and 0.64±0.56 cm*yr–1, respectively. There was no significant relationship between growth rate and initial size or remigration interval. Estimates of population size between 2000 (58 adult females, range: 28-113) and 2006 (277 adult females, range: 133–532) increased both significantly and exponentially (r= 0.966, p= 0.0004), with the study sites representing 1% of estimated world adult female population.