South American Sea Lion (Otaria favescens, Shaw 1800)

Abstract

The South American sea lion is distributed almost continuously from Zorritos, Peru, on the Pacifc Ocean to Torres, Brazil, on the Atlantic Ocean. The total population was estimated at 445,000 individuals, and the species is considered as Least Concern in the IUCN Red List. Two evolutionarily signifcant units were recognized based on molecular data, a Pacifc and an Atlantic population, with at least two management units in each ocean basin. The species is polygynous and sexually dimorphic, with males being larger and heavier than females. Reproduction occurs during the austral summer, between mid-December and early February. Longevity is close to 20 years for both sexes in free and captive life. The sea lion is an opportunistic species that predates mainly on pelagic, demersal, and benthic species of fish, squids, and crustaceans, some of them of commercial importance. Sea lions were used by aboriginal people as far as 8000 YBP and more recently by Europeans and local inhabitants until the frst half of the twentieth century, mainly for food, leather, and oil. After the cease of hunting, the current major threat for sea lions has been the interaction with all types of fisheries and salmon farms. These include the huge extraction of fish biomass of which many target species are prey of sea lions. Fishermen claim across the entire distribution of the species that sea lions are their competitors, which cause them signifcant economic loss. Environmental education and sea lion watching tourism at haul-out sites are recommended in order to promote conservation of the species.