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Falklands Conservation |
Distribution
Description & Food
Population
History of Exploitation and Declining Numbers
Current Threats
1995 Survey Results
Southern Sea Lions (Otaria flavescens) are distributed along the Atlantic and Pacific coasts of South America from the northern limits of Peru, south to Tierra del Fuego, the Falkland Islands and north on the Atlantic coast to Isla de Torres off the coast of south east Brazil.
Adult males reach a maximum length of about 2.5 metres and weigh up to 700lbs. On land, when dry, the neck hair stands out giving the appearance of a mane. The main foods are octopus and squid with some lobster krill and fish. They usually feed in kelp beds and often at night. They have been not uncommonly recorded preying on penguins, particularly Gentoos.
In the 1930s the Falkland Islands held a large proportion of the world's population of the Southern Sea Lion. Over 80,000 pups were born in the Falklands each year, equivalent to a total population of 380,000 animals. The population has declined dramatically since then. In 1965 an air survey of the entire archipelago produced an estimate of only 6,000 pups. A survey conducted in 1995 counted a total of only 5,574 sea lions in the Islands.
History of Exploitation and Declining Numbers
Seals throughout the Southern Ocean were subjected to severe exploitation during the 18th and 19th centuries. In the Falkland Islands, South American Fur Seals (Arctocephalus australis) Southern Elephant Seals (Mirounga leonina) and Southern Sea Lions were hunted. By the early 1900s, Fur and Elephant seal numbers had declined to the point where commercial harvesting was no longer profitable but hunting of Southern Sea Lions continued. Approximately 40,000 were taken in the period 1928-38, 3,000 in 1949-51 and 1500 in 1962 (Strange 1979). Exploitation at these levels, while probably a contributory factor, would not have been sufficient to account for the rate or extent of the decline. There are no reports of large scale illegal hunting in the Falkland Islands or of mass mortalities which might account for the crash. Until recently there were no major fisheries in the region so no potential for conflict with fishing operations.
In recent years there have been three developments which could directly or indirectly affect the Sea Lion population and its chances of recovery: 1) A major squid and fin fish fishery has developed which could affect Sea Lions directly by entanglement or indirectly through competition for prey. 2) The Islands have become increasingly popular as a destination for wildlife tourism which could lead to increased levels of human disturbance. 3) Oil companies are currently prospecting for oil on the shelf between the Falkland Islands and Argentina which could lead to increased levels of disturbance both on land and at sea.
In 1995 Falklands Conservation commissioned a survey (conducted by the Sea Mammal Research Unit) of Sea Lions in the Islands to assess the current population and develop a conservation strategy for Sea Lions in the Islands. This count has established that the current population of Sea Lions in the Falklands represents only 2.5% of the count obtained in the 1930s. From 103 groups found after visiting 191 separate islands and mainland sites a total of 5,574 sea lions were counted. The results of the 1995 survey are published in Southern Sea Lions (Otaria flavescens) in the Falkland Islands: Populations size, foraging behaviour and diet available from Falklands Conservation price £15.00.
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Patron: HRH The Duke of York CVO ADC Member of the International Union for Conservation of Nature | BirdLife International Representative |