South American Sea Lion(Otaria flavescens)
They are also known as the Southern Sea Lion and the Patagonian sea lion. Males have a very large head with a well-developed mane, making them the most lionesque of the eared seals. They are twice the weight of females. Both males and females are orange or brown coloured with upturned snouts. Pups are born greyish orange ventrally and black dorsally and moult into a more chocolate colour. The South American sea lion's size and weight can vary considerably.
Adult males can grow over 2.73 m and weigh up to 350 kg. Adult females grow up to 1.8–2 m and weigh about half the weight of the males, around 150 kg. This species is even more sexually dimorphic than the other sea lions. On land sea lions will use their rear flippers to walk, climb and gallop, and thus can move surprisingly fast.
Habitat
The South American sea lion lives along the South American coastlines on the Atlantic side from Rio de Janeiro to Perú on the Pacific side in southernmost South America. Some have been known to occur in the Falkland and Galapagos Islands. They live along shorelines and beaches, which usually consist of sand, rocks, gravel and/or pebbles. They also occur on flat rocky shelves or on cliffs with boulders and tide pools.
Diet
A South American sea lion are carnivores (piscivores) and eat fish, cephalopods, and crustaceans, as well as other invertebrates, depending on what is available locally. They have even been observed preying on penguins, pelicans, and young South American fur seals. South American sea lions may forage at the ocean floor for slow-moving prey or hunt schooling prey in groups, depending on the area. When captured, the prey is shaken violently and torn apart.
Breeding
They breed on beaches made of sand, gravel, rocky, or pebble beaches. They can also be seen on flat, rocky cliffs with tide pools. Sea lion colonies tend to be small and scattered, especially on rocky beaches. The colonies make spaces between each individual when the weather is warm and sunny. They can also be found in marinas and wharves, but do not breed there.This sea lion has a polygynous lifestyle. The mating season runs from early August until December, when males will defend their territories aggressively and show an interest in females. Mating behaviors include mutual vocalizations, mouth and snout contact, smelling, and some playful biting. Gestation is for about 11-12 months, and usually one pup is born. Mothers mate again soon after birth with the male whose territory the birth took place in. Pups spend most of the day in pods or groups playing, sleeping, or staying near the water. They first go into the water usually after about 3 to 4 weeks in a large group with other sea lions. Pups nurse for around 6 to 12 months, until their mother bears another pup, though some mothers nurse both pups at the same time. Male pups are sexually mature by 6 years of age, and females at 4, and both genders are full adult size at about 8 years of age.
Population
South American sea lion is the most abundant marine mammal across its range. According to the IUCN Red List, the total South American sea lion population size is around 445,000 individuals, including approximately 222,500 mature individuals. Currently this species is classified as Least Concern (LC) and its numbers today remain stable.
Threats
The Southern sea lion has been killed in the past for the fur trade, causing a significant decrease in numbers. Today it is illegal in Argentina to kill sea lions but populations are still declining as a result of fisherman shooting sea lions that swim into their fisheries. Another threat is drowning in fishing nets. Fishing gear was also found in stomachs of dead animals.
Conservation
South American Sea Lions are protected and managed by laws in most of the countries where they occur. Sea lions have also been afforded protection by the establishment of numerous reserves and protected areas at rookeries and haul out sites, especially in Argentina. However, enforcement of protective regulations is weak in most of the distribution range, particularly in the most isolated areas and at sea. In Peru it is illegal to poach, export, or transport South American Sea Lions for commercial purposes. After the population decline that followed the 1997-1998 ENSO led to the South American Fur Seals being categorized as in danger of extinction in Peru, Sea Lions in Peru were re-categorized as Vulnerable. In Chile, the South American Sea Lion is the only marine mammal species that is considered a productive resource and thus is suitable for exploitation. Since 2004 and for five years there has been a moratorium that could be lifted if the interaction with fisheries is shown to be detrimental to the fisheries. In 2006, for the first time, a Sea Lion harvest quota was established for the aboriginal populations of the Magallanes region, thus helping with the conservation of their traditions. Finally, in 2008 the capture of live Sea Lions was authorized for exhibitions, as well as the capture of animals dangerous to human health. The moratorium has been renewed since 2004 and exploitation is currently banned in Chile. In Uruguay, the South American Sea Lion was declared a priority species for conservation by the SNAP and was named as a focal object of conservation in the Marine Protected Area of Cabo Polonio. Since 2011, a community-based participatory research program (POPA) is being developed where the use of pound nets is evaluated to mitigate the interaction between Sea Lions and artisanal fishing in Piriápolis. In Brazil, all the pinniped species have been under protection since 1986 by law and also by the National Action Plans for Conservation of Brazilian Aquatic Mammals. South American Sea Lions have also been afforded protection by the establishment of numerous reserves and marine protected areas (MPAs), including privately owned sites.
It was suggested that the participation of fishermen will be essential to develop real strategies for sustainable tourism and for the future management plan of any marine protected area (MPA) with South American Sea Lions. According to the authors the future management plans should include: (1) environmental education that highlights the ecological importance of the MPA; (2) campaigns that highlight the potential sustainable use of the area for ecotourism; and (3) transforming the Sea Lion to a flagship species of the region. Finally, it is important that all these strategies be targeted to all groups (e.g., tourists, local children, and politicians), and not only for the fishing community.