South American Fur Seal
(Arctocephalus australis)
| Distribution and Numbers Also known as the Southern fur seal, there are probably between 300,000 and 450,000 South American fur seals, distributed from Península Paracas in southern Peru around the rocky coasts of South America as far as Rio Grande do Sul in southern Brazil. Exact population numbers are not available over much of the species' range, but estimates include 5,000 in Peru, 104,000 in Chile (now probably much lower than this, possibly 40,000 - 50,000, after the 1997-98 El Niño event), 20,000 in Argentina, and 15,000 - 16,000 in the Falkland Islands. A figure of 280,000 - 310,000 fur seals has been reported for Uruguay but this is now fairly old and is thought to be an overestimate of the current population size. |
 Photo: Enrique Páez, Instituto Nacional de Pesca, Uruguay |
| There are no breeding colonies in Brazil, the small number of
individuals found there originating from the Uruguayan and Argentinean rookeries to the
south. |
| Status The South American fur seal is listed as an Appendix II species under CITES. Commercial hunting of South American fur seals is known to have taken place in Uruguay as early as 1515 and continued there with varying intensities through the centuries. The seals were killed for their fur, leather, oil and also the genitalia of the males which were exported to Asian countries for the aphrodisiac trade. At least 750,000 fur seals were killed in Uruguay from 1873 to 1983 and nearly 64,000 fur seal pelts were obtained in southern Chile between 1873 and 1907. A total of 9,600 fur seals were also killed in Chile between 1976 and 1979. The hunting of fur seals was banned in Uruguay in 1991 and there is now no commercial hunting of the species in any of its range countries. |
| There are currently plans however to build a fur factory in Uruguay to process the pelts from fur seals, and there is concern that the government may be planning to propose a cull of the species. Regular calls for a fur seal cull are made by Uruguayan fishermen who, mostly misidentifying South American sea lions, claim that the fur seals are destroying their nets and stealing their catch. The income to be made from the export of male fur seal genitalia for the aphrodisiac trade is also acting as an incentive for renewed hunting. A pilot seal-watching venture has been in operation in Uruguay since June 1996 and it was hoped that the income generated from this activity could reduce pressure for a cull. However so far the venture has not been commercially successful. The species has been protected in Peru since 1959 but poaching is still common there. There has been evidence in the past of fishermen in Chile and, to a lesser extent, Argentina, killing fur seals as bait for the king crab fishery, but it is not known if this practice continues. |
| In February 1997 an oil tanker spilled 4,000 - 5,000 cubic metres of crude oil off the coast of Uruguay, killing 6,000 fur seals, mostly pups. The increased exploitation of oil in South America and the high density of South American fur seal breeding colonies leaves them highly sensitive to the effects of such oil spills. |
 Photo: Miguel Iñíguez, Fundacion Cethus |
South American fur seals on the Pacific Ocean coast have also been affected by El Niño events which reduce food availability by affecting the flow of the nutrient-rich Peruvian (Humboldt) current. The strong El Niño event of 1982-83, for example, almost exterminated the entire 1982 pup production in Peru and also drove a portion of the Peruvian population into northern Chile where it subsequently became established. The 1997-98 El Niño may have killed as many as 80% of the Peruvian population of fur seals. Since then, the population in Peru has recovered only at a very slow rate, mostly because the El Niño killed not only the year's pups but also a significant portion of the adult female population. |
| There is not much interaction of the species with coastal fisheries as
the South American fur seal tends to feed out at sea. However some interactions with
salmon farms in Chile have been reported. Drift gill nets placed in the transit routes of
fur seals may also contribute significantly to mortality of the species in Peru and Chile.
The impact of intensive commercial fishing is thought to affect available food resources
and has been blamed for the lack of increase in the fur seal population in Patagonia as
well as the depletion of the important anchovy prey in the southern Pacific Ocean. |
| Lifestyle The South American fur seal breeding season takes place from October to December. The adult males compete to form territories which they then defend during the season. In some colonies the intense sun and heat force the males to maintain their territories in the intertidal zone where there is permanent access to water, while the females move regularly with their pups between the high dry land and the water to cool down. |
| Pups are born with a black coat. About 5-10 days after her pup's birth, the mother mates and then begins a cycle of alternately going to sea for 3-5 days on foraging trips and returning to nurse her pup for an average of 1 and a half days. The mortality rate of pups has been shown to be dependent on the density of the breeding colony, due partly to accidental mother-pup separation and also to aggression from adults. The average mortality in the first month after birth has been observed as high as 31-49% in the very dense Peruvian colonies, the highest rate of any fur seal population. As a consequence of the effects of El Niño in Peru, breeding densities there have now dropped significantly and the first month mortality of pups does not now exceed 15%. The mother usually nurses her pup for 6-12 months but it has been known for females in Peru to nurse their pups for up to 3 years, particularly if there has been an El Niño event during the nursing period. Most females remain at or near the breeding beaches all year round, but the movements of males outside the breeding season are not well known. |
| Adult male South American fur seals have a blackish-grey
coat while females and sub-adult males are greyish-black with a lighter front. Adult seals
in Peru feed almost exclusively on anchovies, the juveniles feeding on demersal fish. In
Uruguay the seals eat anchovies and other fish species while shrimps and fish in Brazil
and fish and lobster krill in Chile are important components of the seals' diet. Studies
have shown that lactating females dive and feed almost exclusively at night to a depth of
40m and for periods of about 3 minutes. South American fur seals pups are regularly killed
on the Peruvian beaches by male South American sea lions, an occurrence also observed to
some extent in the Uruguayan population. South American fur seals are also killed by
sharks and killer whales. |
 Photo: Enrique Páez, Instituto Nacional de Pesca, Uruguay |
| Statistics There is some variation in body size over the species' range. Adult male seals in Uruguay, for example, are about one and a half times the size of those in Peru, while adult females in Uruguay are only about three quarters of the size of those in Peru. Adult males can measure up to 2m long and weigh 150 - 200kg, the females smaller, measuring up to 1.5m long and weighing 30 - 60kg. Pups weigh 3.5 - 5.5kg and measure 55 - 65cm long at birth. South American fur seals have been observed diving to depths of up to 170m for up to 7 minutes. Females reach sexual maturity at 3 years of age, males at 7 years. The earliest that adult males are known to achieve territorial status is about 8 years of age. |
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