|Scientific Name:||Arctocephalus australis|
|Species Authority:||(Zimmermann, 1783)|
|Infra-specific Taxa Assessed:|
Arctophocoa australis (Zimmermann, 1783)
|Taxonomic Notes:||Two subspecies have been described: Arctocephalus australis australis (Zimmerman, 1783) for the Falkland subpopulation and Arctocephalus australis gracilis (Nehring, 1887) for the mainland subpopulation. Animals from the Falkland subpopulation have been reported to be larger than animals from the South American coastal subpopulation (Rice 1998). However, the validity of these subspecies is disputed (Reijnders et al 1993).|
|Red List Category & Criteria:||Least Concern ver 3.1|
|Assessor(s):||Campagna, C. (IUCN SSC Pinniped Specialist Group)|
|Reviewer(s):||Kovacs, K. & Lowry, L. (Pinniped Red List Authority)|
Due to its large and increasing population size, the South American Fur Seal should remain classified as Least Concern.
IUCN Evaluation of the South American Fur Seal, Arctocephalus australis
Prepared by the Pinniped Specialist Group
A. Population reduction Declines measured over the longer of 10 years or 3 generations
A1 CR > 90%; EN > 70%; VU > 50%
Al. Population reduction observed, estimated, inferred, or suspected in the past where the causes of the reduction are clearly reversible AND understood AND have ceased, based on and specifying any of the following:
(a) direct observation
(b) an index of abundance appropriate to the taxon
(c) a decline in area of occupancy (AOO), extent of occurrence (EOO) and/or habitat quality
(d) actual or potential levels of exploitation
(e) effects of introduced taxa, hybridization, pathogens, pollutants, competitors or parasites.
No integrated census data are available for the entire distribution range. Most of the population is concentrate on a few islands of Uruguay and the best available data suggest that numbers are expanding. A population decrease is possible for the Pacific side of the distribution and may be = 50% for colonies breeding in Chile. The Peruvian population is also under the strong impact of El Niño. In Argentina, the population is relatively small, but it is increasing. Due to a large proportion of the global population being stable or perhaps increasing, the criteria of population reduction do not apply at the species level.
A2, A3 & A4 CR > 80%; EN > 50%; VU > 30%
A2. Population reduction observed, estimated, inferred, or suspected in the past where the causes of reduction may not have ceased OR may not be understood OR may not be reversible, based on (a) to (e) under A1.
Commercial harvesting has ceased and any local reductions are due to El Niño and to competition with fisheries, but these negative effects occur at a local level rather across the entire distribution range. Therefore, these criteria do not apply for the species.
A3. Population reduction projected or suspected to be met in the future (up to a maximum of 100 years) based on (b) to (e) under A1.
A reduction in numbers at the species level may occur if climate change increases the impact of El Niño in the Pacific side of the distribution. However, thus far the numbers in the Uruguayan islands are stable or increasing.
A4. An observed, estimated, inferred, projected or suspected population reduction (up to a maximum of 100 years) where the time period must include both the past and the future, and where the causes of reduction may not have ceased OR may not be understood OR may not be reversible, based on (a) to (e) under A1.
A reduction in numbers at the species level may occur if climate change increases the impact of El Niño in the Pacific side of the distribution. However, thus far as the numbers in the Uruguayan islands are stable or increasing. Local colony reductions are not currently significant in terms of total global population size.
B. Geographic range in the form of either B1 (extent of occurrence) AND/OR B2 (area of occupancy)
B1. Extent of occurrence (EOO): CR < 100 km²; EN < 5,000 km²; VU < 20,000 km²
The EOO is > 20,000 km².
B2. Area of occupancy (AOO): CR < 10 km²; EN < 500 km²; VU < 2,000 km²
The AOO is > 2,000 km².
AND at least 2 of the following:
(a) Severely fragmented, OR number of locations: CR = 1; EN < 5; VU < 10
(b) Continuing decline in any of: (i) extent of occurrence; (ii) area of occupancy; (iii) area, extent and/or quality of habitat; (iv) number of locations or subpopulations; (v) number of mature individuals.
(c) Extreme fluctuations in any of: (i) extent of occurrence; (ii) area of occupancy; (iii) number of locations or subpopulations; (iv) number of mature individuals.
C. Small population size and decline
Number of mature individuals: CR < 250; EN < 2,500; VU < 10,000
Number of mature individuals is likely > 10,000.
AND either C1 or C2:
C1. An estimated continuing decline of at least: CR = 25% in 3 years or 1 generation; EN = 20% in 5 years or 2 generations; VU = 10% in 10 years or 3 generations (up to a max. of 100 years in future)
C2. A continuing decline AND (a) and/or (b):
(a i) Number of mature individuals in each subpopulation: CR < 50; EN < 250; VU < 1,000
(a ii) % individuals in one subpopulation: CR = 90–100%; EN = 95–100%; VU = 100%
(b) Extreme fluctuations in the number of mature individuals.
D. Very small or restricted population
Number of mature individuals: CR < 50; EN < 250; VU < 1,000 AND/OR restricted area of occupancy typically: AOO < 20 km² or number of locations < 5
E. Quantitative analysis
Indicating the probability of extinction in the wild to be: CR > 50% in 10 years or 3 generations (100 years max.); EN > 20% in 20 years or 5 generations (100 years max.); VU > 10% in 100 years
There has been no quantitative analysis of the probability of extinction.
Listing recommendation — Globally, the South American Fur Seal should be classified as Least Concern. However, particular attention should be paid to local populations in the Pacific. It is possible that the Peruvian and northern Chilean populations are a different stock that may qualify for a threatened status.
|Previously published Red List assessments:||
|Range Description:||South American Fur Seals are found on both the Atlantic and Pacific sides of South America, from Isla Marco (Uruguay) to Isla Mayorca (Peru). Most of the population is concentrated in the Atlantic side of the distribution, especially in the Uruguayan islands. Colonies are often difficult to access and are not regularly dispersed. Along the coast of continental Argentina, 12 rookeries have been described, all on islands. Some of these locales are only used as wintering places. Ten colonies are recorded where reproduction takes place within the Falkland-Malvinas. In the Pacific, animals concentrate in southern (Magellanic region) and northern Chile and in central Peru. The species has a discontinuous distribution and it is absent in the coast of Chile from 28-43°S.
Distribution at sea is poorly known. These seals are thought to forage primarily in continental shelf and slope waters. However, there are records of this species occurring more than 600 km offshore. Vagrants have been reported from the Pacific coast of Colombia and the Juan Fernandez Islands, and the species visits southern Brazil regularly.
Native:Argentina; Brazil; Chile (Juan Fernández Is. - Vagrant); Falkland Islands (Malvinas); Peru; Uruguay
|FAO Marine Fishing Areas:||
Atlantic – southwest; Pacific – southeast
|Range Map:||Click here to open the map viewer and explore range.|
|Population:||Most of the global population of South American Fur Seals is concentrated in Uruguay (200,000-250,000 animals). About 55% of the fur seals in Uruguayan waters are found at Isla de Lobos (ca. 180,000 animals; ca. 35,000 pups born per year). The remaining animals are distributed in the area of Cabo Polonio and Islas de la Coronilla. An additional 15-20 000 animals are found in the Malvinas-Falklands. The population along the Argentine Patagonian coast is about 20 000 animals (the largest colony is in Isla Rasa with 12 000 fur seals). The Chilean population is estimated to be 30 000 fur seals. The Peruvian population was estimated to be 11,400 during an El Niño year (Arias-Schreiber 1998). Therefore, the population global population is roughly 250-300 000 fur seals. The population of coastal Patagonia is increasing at about 8% per year. A decrease from 102,000 to 30.000 has been reported for the Chilean population (Sielfeld 1999, Venegas et al. 2002). El Niño years have dramatic effects on the Peruvian population.|
|Current Population Trend:||Increasing|
|Habitat and Ecology:||South American Fur Seals are sexually dimorphic. Adult males are approximately 1.3 times longer and 3.3 times heavier than adult females. Adult males reach 1.9 m and 120–160, and possibly 200 kg; females are about 1.4 m long and weigh 40-50 kg. Newborns are 60-65 cm and 3.5-5.5 kg. Most females give birth for the first time when they are 4 years old. Pups are born shortly after females return to the colonies. Oestrous occurs 7–10 days later, and following mating, a female begins to make foraging trips punctuated by time attending the pup ashore. Pups are weaned at 8 months to 2 years of age. Females will nurse a yearling and newborn pup at the same time.
Breeding takes place from mid-October through mid-January. The timing of breeding may differ in the Peruvian and Chilean-Atlantic colonies. Colonies are generally found along rocky coasts, on ledges above the shoreline or in boulder strewn areas. Most areas utilized have some source of shade such as at the base of cliffs or under boulders and easy access to the ocean or tidal pools. Males are polygymous and territorial, and fighting can result in dramatic wounds and scars. Individual bulls can occupy territories for up to 60 days and have up to 13 females on their territories at Uruguayan colonies. Male vocalizations include a bark or whimper, a guttural threat, and a submissive call. Females growl and have a pup-attraction call that is a high-pitched wail.
Time spent on trips and attending the pup likely varies with location and changes in marine productivity; El Niño years have a negative impact on animals in Peru and during them females must spend much more time attempting to forage. Female attendance in Uruguay is affected by weather with females spending less time ashore during the day when ground temperature exceeds 36ºC and more time ashore during storms. Survival rates of pups can be quite low when marine productivity is low and storm surges can sweep large numbers of pups off colonies. Locally, pup morality inflicted via predation by adult male South American sea lions can be significant at some colonies. Data collected on adult female South American fur seals during an El Niño event resulted in mean dives to 29 m, with a maximum of 170 m and mean duration of 2.5 minutes and maximum dive length of 7 minutes.
The population along the coast of Patagonia is linked to the Uruguayan colonies. Very few births occur in the Patagonian population, so the recent increases in numbers in this area are almost certainly due to a migration from the Uruguayan islands. It is possible that a similar movement occurs between the Staten Island colony and the Chilean colonies via the Beagle Channel.
At sea, these fur seals may be seen travelling or rafting at the surface in groups. South American Fur Seals will "porpoise,” or leap clear of the water when moving rapidly at sea, sometimes travelling like this in large groups. While resting at the surface they spend considerable time grooming and assume many poses typical of southern fur seals, including waving both hind flippers in the air while the head is submerged. Groups often form in the water at the base of a colony. They are frequently seen grooming while resting at the surface.
Demersal and pelagic fishes make up the majority of the diet in Uruguay and include: Anchoveta, weakfish, cutlassfish, and anchovy. Cephalopods, lamellibranchs and gastropods are also taken. Additional prey taken in other areas includes sardines, mackerel, hakes and crustaceans such as lobster krill in southern Chile and the Falkland Islands where squid is also a common prey item.
Human subsistence hunting of South American Fur Seals undoubtedly began with first contact and continues today. Commercial exploitation began after the discovery of South American Fur Seals by Europeans in the 18th century. Harvest levels declined in the 20th century bringing about the cessation of hunting at many locations. A managed harvest of adult males continued in Uruguay until recent times (Vaz-Ferreira and Ponce de Leon 1987). Small numbers of fur seals are taken for subsistence and poached for human food in Chile in Peru. Animals are often shot in the coastal areas of Peru and an estimate yielded that up to 35% of the dead seals found on beaches have been shot.
Extensive development of large-scale commercial fisheries and ongoing, numerous small-scale coastal fisheries have had an unknown effect on the amount of food available to South American Fur Seals. These fisheries are also a source of entanglements and direct mortality.
In southern Chile, seals were illegally exploited some time ago as a source of free bait for the king crab fishery. Because this fishery is decreasing due to overexploitation, hunting pressure on the fur seal is being reduced, although incidental captures in shark nets have been reported for Uruguay (Scialabba 1989). Small numbers of fur seals are also caught in the Chilean trawl-fisheries.
Survival rates of pups can be quite low when marine productivity is low and storm surges can sweep large numbers of pups off colonies. During El Niño years, mortalities of 100% of pups born have been recorded. Also, high mortality rates of pups occur in dense colonies.
The limited number of large, dense breeding aggregations could make this species particularly sensitive to the effects of oil spills and disease epidemics. Like all fur seals, South American Fur Seals are vulnerable to oil spills because of their dependence on their thick pelage for thermoregulation.
It is listed on CITES Appendix II. South American Fur Seals are protected and managed by laws in most of the countries where they occur. In Chile, the status of total protection was given to all Arctocephalus species in 1978 (Torres 1987, Reijnders et al 1993). In Argentina, marine mammals are under the administration of the various provinces. At the Falkland Islands (Malvinas) fur seals are protected by British law. South American Fur Seals have also been afforded protection by the establishment of numerous reserves and protected areas, including privately owned sites.
Particular attention should be paid to local populations in the Pacific. It is possible that the Peruvian and northern Chilean populations are a different stock that may qualify for a threatened status.
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|Citation:||Campagna, C. (IUCN SSC Pinniped Specialist Group). 2008. Arctocephalus australis. The IUCN Red List of Threatened Species 2008: e.T2055A9211535. . Downloaded on 25 June 2016.|