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.

BACKGROUND Queen conch Aliger gigas (Linnaeus, 1758), formerly known as Strombus gigas, constitute a valuable commercial and cultural resource for native communities since pre-Hispanic times (Baisre, 2010). Populations of this marine gastropod are registered for 36 countries in the Caribbean, extending from Florida to the northern coast of South America and live mainly on sandy bottoms, in clear waters down to a depth of 100 m (CITES, 2003). Mating and spawning usually take place during the warmer months of the year, although in some areas, mainly in the western Caribbean, the breeding activity is continuous at low reproduction levels throughout the year (Avila-Poveda and Baqueiro-Cardenas, 2009; Aldana-Aranda et al., 2014; Boman et al., 2018). Moreover, some populations migrate seasonally from open waters to shallower waters for spawning (Appeldoorn, 1993). Over the past decades, intensive overfishing has led to population decline, collapse of stocks, and temporary closure of fisheries in different locations at Bermuda,

The tuna purse seine fishery is a large-scale fishery in the Colombian Pacific Ocean (CPO). This study aims to perform a descriptive and spatiotemporal analysis of the purse-seine tuna fishery in the CPO to provide new knowledge and alternatives for its domestic management. Georeferenced data (2000 -2019) allowed the analysis by species, vessel carrying capacity, and fishing method. Yellowfin Tuna-YFT (Thunnus albacares) and Skipjack Tuna-SKJ (Katsuwonus pelamis) were the most captured species. The Not Associated method (NoAs) was mostly used in the first decade, while the method associated with Dolphins (DEL) was mainly used in the second. The natural floating objects method (NAT) was the least used method, while the fish aggregating device method (FAD) was the most used. There was no clear annual catch pattern with discrete peaks in May and October. The average number of sets per year was 1,230, and only 8.7% of the tuna was captured by the Colombian tuna fleet in the CPO. Capture per Unit Effort oscillated from 14.9 to 27.2 t/effective set/ year. The spatiotemporal analysis showed four main fishing grounds; YFT was mainly fished in the northwestern zone and near the coast, while SKJ was captured in almost all CPO; the main fishing activity is performed by the largest vessels, showing significantly higher tuna catches. The DEL method is used mainly in the central area and towards the coast, while FAD is used in most of the CPO. It is important to work on the FAD regulation, small tuna discards, increase the fishing observer coverage, satellite, and onthe-field vessel monitoring, and characterize environmental conditions related to tuna fishing. Furthermore, tuna fishing should be considered in the initiatives to establish new protected areas in the CPO.