Abstract

Shark capture in the state of Yucatan has increased from 450 ton in 1975 to 1,300 in 1994, thus occupying 4th place by its economic value and 7th place in importance considering its capture volume at the national level. Although the biological and fishing knowledge of this resource is essential to establish the rules for its management, little is known about the abundance and spatial-temporal distribution pattern of the species. The objective of the present study was to contribute to the knowledge of the population structure of the shark resource in Yucatan platform. The information gathered from 1985 to 1991 comes from ship records (knowledge of fishing area, depth, composition and weight of the capture, meristic data) and fishing landings (biological data). For the analysis of the community structure by zones and depth, a binary matrix of data was built (presence/absence) and multivariate analyses were carried out. The capture is composed of 27 species within 9 families. Dominant species, considering Sanders Index, were Carcharhinus falciformis, Rhizoprionodon terranovae, Mustelus norrisi and Sphyrna tiburo as well as Hexanchus vitulus, a species that was not reported before for the area. Five fishing areas were identified, and the east of the state was the one with the most fishing pressure. Most shark species showed a seasonal pattern, being captured most frequently during summer and autumn. In capture terms, the genus Carcharhinus supported the shark fishery with almost 50% of the records. Diverse association levels were obtained between species and areas. In relation to administration, the information doesn't allow formulation of regulations. However, already some preliminary recommendations have been considered, with a suggestion to not increase the fishing permissions for shark capture. It is concluded that some shark species in the Yucatan coast have suitable areas for living and breeding, but they have been subjected to heavy fishing efforts that could generate in the near future the collapse of this resource

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