Population dynamics of the exploited sea cucumber Isostichopus fuscus in the western Galapagos Islands, Ecuador

Long-term density data for the sea cucumber, Isostichopus fuscus, from Canal Bolivar (separating western Isabela and eastern Fernandina Islands), Galapagos, were compared with catch statistics and used in a stock depletion model to determine the extent of the effects of the fishery on the existing population and the potential for the population to recover after each fishing season. Recruitment indices were found to be low from 1994 until mid-1999, when a mass recruitment event was registered and numbers of small individuals increased dramatically. The increase in density of juveniles peaked in 2001 and has declined since. Recruitment in this species of sea cucumber appears to be highly sporadic and may depend on intense climatic events such as the warm El Nino. Current levels of fishing activity are unsustainable. The management implications of pulse recruitment in this fishery are discussed.