Abstract

Swordfish is widely distributed along the Venezuelan coast. Until 1987, swordfish was a by-catch product of the tuna longline fishery. By this time the swordfish fishery in the southern United States had expanded their range to less utilized fishing areas of the Caribbean, including Venezuela. The significant increase in the catches of this resource led to the development of a swordfish fishery. Since swordfish in the North Atlantic is managed as a single stock by the International Commission for the Conservation of Atlantic Tunas, it was necessary to determine the population structure in Venezuela and adjacent waters. A total of 2,580 specimens have been collected between May 1991 and June 1994. Seasonal female sexual maturity is assessed from 646 ovaries using a gonadal index (GI). Results indicate that the catches are comprised of animals with mean size of 135.1 cm LJFL for females and 123.4 cm LJFL for males and 50% of the catch is made up of specimens less than 130 cm LJFL. Seasonal sex ratio show an in reased proportion of females (60%), except in March and June where the proportion of males increases (55-65%). Mean female gonadal indices show little variation throughout the season(GI<1.0), sexually mature females show some prespawning activity towards the fourth quarter of the year. Only one specimen with hydrated oocytes was obtained in the samples. These results indicate that the population structure of the swordfish catch in Venezuela and adjacent waters is mainly comprised of sexually immature females and young sexually mature males. Occasional spawning is restricted to the last quarter of the year.

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