Brown fur seal

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Brown fur seal
Arctocephalus pusillus - SE Tasmania.jpg
Hauling-out on the Hippolyte Rocks off the east coast of Tasmania
CITES Appendix II (CITES) [2]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Clade: Pinnipedia
Family: Otariidae
Genus: Arctocephalus
Species:
A. pusillus
Binomial name
Arctocephalus pusillus
(Schreber, 1775)
Subspecies
  • A. p. pusillus(Cape/South African fur seal)
  • A. p. doriferus(Australian fur seal)
Arctocephalus pusillus distribution.png
Distribution of the brown fur seal, dark blue: breeding colonies; light blue: nonbreeding individuals

The brown fur seal (Arctocephalus pusillus), also known as the Cape fur seal, South African fur seal and Australian fur seal, is a species of fur seal.

Description

Skull of male Arctocephalus pusillus01.jpg
Skull of male

The brown fur seal is the largest and most robust member of the fur seals. It has a large and broad head with a pointed snout that may be flat or turned up slightly. [3] They have external ear flaps ( pinnae ) and their whiskers ( vibrissae ) are long, possibly growing back past the pinnae, especially in adult males. The fore-flippers are covered with sparse hairs over about three-quarters of their length. The hind-flippers are short relative to the large body, with short, fleshy tips on the digits. [3] The size and weight of the brown fur seal depends on the subspecies; the Southern African subspecies is, on average, slightly larger than the Australian subspecies. Males of the African subspecies (A. p. pusillus) are 2.3 m (7.5 ft) in length on average and weigh 200–300 kg (440–660 lb). [4] Females are smaller, averaging 1.8 m (5.9 ft) in length and typically weighing 120 kg (260 lb). [5] Males of the Australian subspecies (A. p. doriferus) are 2.0–2.2 m (6.6–7.2 ft) in length and weigh 190–280 kg (420–620 lb). [6] Females are 1.2–1.8 m (3.9–5.9 ft) length and weigh 36–110 kilograms (79–243 lb). [5]

Adult male brown fur seals are dark gray to brown, with a darker mane of short, coarse hairs and a lighter belly, while adult females are light brown to gray, with a light throat and darker back and belly. The fore-flippers of the fur seal are dark brown to black. [3] Pups are born black, molting to gray with a pale throat within 3–5 months. [3] The skull of the African subspecies has a larger crest between the mastoid process and the jugular process of the exoccipital. [5]

Ecology

Baby seal Arctocephalus pusillus 4 - Cape fur seal.JPG
Baby seal
A fur seal colony at Duiker Island, South Africa Fur Seals on Duiker Island.JPG
A fur seal colony at Duiker Island, South Africa
Fur seal underwater at Agulhas Bank Seal at the Cape Town Scuba Diving.jpg
Fur seal underwater at Agulhas Bank
Cape Cross colony, Namibia Arctocephalus pusillus 5 - Cape fur seal.JPG
Cape Cross colony, Namibia

The African fur seal inhabits the southern and southwestern coast of Africa, from Cape Cross, Namibia to around the Cape of Good Hope and from Black Rocks, near Port Elizabeth in the Eastern Cape province. [3] The Australian fur seal lives in the Bass Strait, on four islands off Victoria (southeastern Australia), and five islands off Tasmania. [3] Brown fur seals prefer to haul-out and breed on rocky outcrops and small islands, rock ledges and exposed reefs, as well as on rocky, pebble or boulder beaches. However, some larger colonies can be found on sandy beaches, such as in South Africa. [3] Fur seals spend most of the year at-sea, but are never too far from land. They have been recorded 160 km from land, but this is not common. [5]

The African fur seal's diet is made of up to 70% fish, 20% squid, and 2% crab. [7] Also eaten are other crustaceans, cephalopods and sometimes seabirds. [5] [7] In rare instances, they have even been documented attacking and eating sharks. A recent incident occurred off Cape Point, South Africa, where a large male was observed attacking and killing five blue sharks between 1.0 and 1.4 m long. Observers concluded that the seal likely killed the sharks to eat the fish-rich contents of their stomachs, as well as their livers, as a source of energy. [8] The Australian fur seal mostly eats squid, octopus, fish, and lobsters. [5] [7] The brown fur seal dives for its food. The African subspecies can dive as deep as 204 m (669') for as long as 7.5 minutes. [9] The Australian subspecies generally feeds at lower depths, diving an average of 120 m [7] (394'), and going as deep as 200 m (656'). [9]

The brown fur seal's main predators are the great white shark, and orcas (killer whales), as well as occasionally vagrant southern elephant seals. [10] African land-based predators, primarily of pups, include black-backed jackals, brown hyenas and occasionally lions [11] on the Skeleton Coast in Namibia. In addition, seagulls and other seabirds are thought to peck the eyes out of baby seals, especially sick or injured individuals, to render them helpless and disabled, as they begin to feast on their flesh. [12]

In False Bay, the seals employ a number of defensive strategies while in shark-infested waters, such as:

Behaviour

Brown fur seal colony at Friar Islands, Tasmania Arctocephalus pusillus Colony Friar Island.jpg
Brown fur seal colony at Friar Islands, Tasmania
Brown fur seals in Cape Cross Arctocephalus pusillus (Cape fur seals).jpg
Brown fur seals in Cape Cross

Acoustic behavior

Australian fur seals are social animals that use vocalizations in a broad range of contexts. These vocalizations have been shown to contain individually unique properties important for enabling individual recognition. [14] This is particularly important for the reunion of mothers and pups that experience repeated separations whilst mothers are out at sea foraging, sometimes for days at a time. Upon their return, mothers need to locate their pups. [15] [16] This reunion process may also be facilitated through a combination of smell and spatial cues.

In males, increases in testosterone and calling rates are seen in conjunction with the onset of the breeding season. [17] Males can also differentiate neighboring males from stranger males, responding more aggressively to the vocalizations of strangers. [18] This difference in response is suspected because the threat posed by a stranger is unknown and potentially greater than their neighbor, which they would have previously encountered while establishing their territories. [19] [20]

Breeding behaviour

Brown fur seals often gather into colonies on rookeries in numbers ranging from 500 to 1500, at least for the Australian subspecies. [5] While fur seals spend most of the year at sea, they never fully evacuate the rookeries, as mothers and pups return to them throughout the year. No dispersal from a colony is established, although some fur seals from one colony have been found at another. True boundaries do not exist between the colonies. When at sea, they travel in small feeding groups. Brown fur seals begin to breed in the middle of October, when males haul out on shore to establish territories though display, vocalisations, sparring, and sometimes actual combat. [21] They fast at this time and do not eat until after mating in November or December. When the females arrive, they fight among themselves for territories in which to give birth. Female territories are smaller than those of males and are always located within them. Females within a male's territory can be considered part of his harem. However, males do not herd the females, which are free to choose their mates and judge them based on the value of their territories. For the Australian fur seals, 82% of copulations are performed by males whose territories are located directly at the water's edge. [9] Copulation between the male and his females begins 6 days after they give birth to their pups conceived from the previous year. However, a delay occurs in the implantation of the blastocyst, which lasts 4 months in the African subspecies and 3 months in the Australian subspecies. [9] Gestation for the brown fur seal typically lasts a year less a few days. [9]

Suckling Arctocephalus pusillus 3 - Cape fur seal.JPG
Suckling

After mating, females begin alternating brief periods of foraging at sea with several days ashore nursing their pups. [3] Foraging trips last about 7 days in winter and about 4 days in summer and autumn. When a mother returns from sea to feed her pup, she emits a loud call which attracts all the nearby pups, but she only responds to her pup. She possibly can recognize her pup by smell. [9] When left alone, pups gather in groups and play during the evening. [5] Pups are usually weaned at 4–6 months old. [3]

Human interactions

Brown fur seal Gaston in Prague Zoo Seal Gaston.jpg
Brown fur seal Gaston in Prague Zoo
Fur seals used for tourist attraction in Namibia Fur seal, Walvis Bay (Namibia).jpg
Fur seals used for tourist attraction in Namibia

This species is an inquisitive and friendly animal when in the water, and often accompanies scuba divers. They swim around divers for periods of several minutes at a time, even at a depth of 60 m. On land, they are far less relaxed and tend to panic when humans come near them.

Australian fur seals were hunted intensively between 1798 and 1825 for commercial reasons. Seal hunting stopped in Australia in 1923, and their population is still recovering, causing increasing friction with South Australian fishermen as their range expands. [22] Breeding and haul-out sites are protected by law. South African fur seals have a very robust and healthy population. Harvesting of seals was outlawed in South Africa in 1990.

Brown fur seals are still harvested in Namibia. Permits are issued for the killing of pups for their luxurious fur and adult males for their genitalia, which are considered an aphrodisiac in some countries. It is also considered necessary to limit seal numbers in Namibia because of the supposed effect seals have on the country's fish harvest. Research by environmental groups disputes this. [23]

In January 2023, media reports indicated that seals have been attacking humans in South Africa, particularly in Cape Town area. Scientists believe it is due to the presence of a brain-altering poison in the fish they consume. The poison is affecting their behavior and making them more aggressive towards humans. Some attribute the aggressive behavior of the animals to the surge of toxic red tide algae, fueled by pollution and climate change. The incidents have increased in recent times, leading to concern and calls for further investigation. [24] [25]

Threat by marine debris and industry

A 2021 study published in The Marine Pollution Bulletin found that the Brown fur seal colonies in Namibia are vulnerable to extensive entanglement in marine debris as a result of extensive pollution in the oceans. [26] The study overall found that juveniles are more prone to become entangled in marine debris, and that 53% of all entanglements discovered were caused by fishing line. [26] Another study by the University of Stirling conducted a similar study on marine pollution and found an almost identical percentage, 52%, of entanglements of brown fur seals were caused by fishing debris. [27]

Ocean Conservation Namibia, a local animal conservation group based in Walvis Bay, was formed specifically by volunteers who capture entangled seals and free them from entanglement discarded by ships and fishing industries. [28] The organization monitors the coast regularly but their founder, Naude Dreyer, told reporters of drastically declining numbers of seals as pollution continues to increase. [29] The organisation has a channel on YouTube, with 1.71 million subscribers as of 4 October 2023.

See also

Related Research Articles

<span class="mw-page-title-main">Fur seal</span> Subfamily of mammals

Fur seals are any of nine species of pinnipeds belonging to the subfamily Arctocephalinae in the family Otariidae. They are much more closely related to sea lions than true seals, and share with them external ears (pinnae), relatively long and muscular foreflippers, and the ability to walk on all fours. They are marked by their dense underfur, which made them a long-time object of commercial hunting. Eight species belong to the genus Arctocephalus and are found primarily in the Southern Hemisphere, while a ninth species also sometimes called fur seal, the Northern fur seal, belongs to a different genus and inhabits the North Pacific. The fur seals in Arctocephalus are more closely related to sea lions than they are to the Northern fur seal, but all three groups are more closely related to each other than they are to true seals.

<span class="mw-page-title-main">Great white shark</span> Species of large lamniform shark

The great white shark, also known as the white shark, white pointer, or simply great white, is a species of large mackerel shark which can be found in the coastal surface waters of all the major oceans. It is the only known surviving species of its genus Carcharodon. The great white shark is notable for its size, with the largest preserved female specimen measuring 5.83 m (19.1 ft) in length and around 2,000 kg (4,410 lb) in weight at maturity. However, most are smaller; males measure 3.4 to 4.0 m, and females measure 4.6 to 4.9 m on average. According to a 2014 study, the lifespan of great white sharks is estimated to be as long as 70 years or more, well above previous estimates, making it one of the longest lived cartilaginous fishes currently known. According to the same study, male great white sharks take 26 years to reach sexual maturity, while the females take 33 years to be ready to produce offspring. Great white sharks can swim at speeds of 25 km/h (16 mph) for short bursts and to depths of 1,200 m (3,900 ft).

<span class="mw-page-title-main">Eared seal</span> Family of marine mammals

An eared seal, otariid, or otary is any member of the marine mammal family Otariidae, one of three groupings of pinnipeds. They comprise 15 extant species in seven genera and are commonly known either as sea lions or fur seals, distinct from true seals (phocids) and the walrus (odobenids). Otariids are adapted to a semiaquatic lifestyle, feeding and migrating in the water, but breeding and resting on land or ice. They reside in subpolar, temperate, and equatorial waters throughout the Pacific and Southern Oceans, the southern Indian, and Atlantic Oceans. They are conspicuously absent in the north Atlantic.

<span class="mw-page-title-main">Sea lion</span> Subfamily of aquatic mammals

Sea lions are pinnipeds characterized by external ear flaps, long foreflippers, the ability to walk on all fours, short and thick hair, and a big chest and belly. Together with the fur seals, they make up the family Otariidae, eared seals. The sea lions have six extant and one extinct species in five genera. Their range extends from the subarctic to tropical waters of the global ocean in both the Northern and Southern Hemispheres, with the notable exception of the northern Atlantic Ocean. They have an average lifespan of 20–30 years. A male California sea lion weighs on average about 300 kg (660 lb) and is about 2.4 m (8 ft) long, while the female sea lion weighs 100 kg (220 lb) and is 1.8 m (6 ft) long. The largest sea lions are Steller's sea lions, which can weigh 1,000 kg (2,200 lb) and grow to a length of 3.0 m (10 ft). Sea lions consume large quantities of food at a time and are known to eat about 5–8% of their body weight at a single feeding. Sea lions can move around 16 knots in water and at their fastest they can reach a speed of about 30 knots. Three species, the Australian sea lion, the Galápagos sea lion and the New Zealand sea lion, are listed as endangered.

<span class="mw-page-title-main">Blue shark</span> Species of shark

The blue shark, also known as the great blue shark, is a species of requiem shark, in the family Carcharhinidae, which inhabits deep waters in the world's temperate and tropical oceans. Averaging around 3.1 m (10 ft) and preferring cooler waters, the blue shark migrates long distances, such as from New England to South America. It is listed as Near Threatened by the IUCN.

<span class="mw-page-title-main">Grey seal</span> Species of carnivore

The grey seal is a large seal of the family Phocidae, which are commonly referred to as "true seals" or "earless seals". The only species classified in the genus Halichoerus, it is found on both shores of the North Atlantic Ocean. In Latin, Halichoerus grypus means "hook-nosed sea pig". Its name is spelled gray seal in the US; it is also known as Atlantic seal and the horsehead seal.

<span class="mw-page-title-main">Leopard seal</span> Macropredatory species of Antarctic seal

The leopard seal, also referred to as the sea leopard, is the second largest species of seal in the Antarctic. Its only natural predator is the orca. It feeds on a wide range of prey including cephalopods, other pinnipeds, krill, fish, and birds, particularly penguins. It is the only species in the genus Hydrurga. Its closest relatives are the Ross seal, the crabeater seal and the Weddell seal, which together are known as the tribe of Lobodontini seals. The name hydrurga means "water worker" and leptonyx is the Greek for "thin-clawed".

<span class="mw-page-title-main">Antarctic fur seal</span> Species of carnivore

The Antarctic fur seal is one of eight seals in the genus Arctocephalus, and one of nine fur seals in the subfamily Arctocephalinae. Despite what its name suggests, the Antarctic fur seal is mostly distributed in Subantarctic islands and its scientific name is thought to have come from the German vessel SMS Gazelle, which was the first to collect specimens of this species from Kerguelen Islands.

<span class="mw-page-title-main">Subantarctic fur seal</span> Species of carnivore

The subantarctic fur seal is a species of arctocephaline found in the southern parts of the Indian, Pacific, and Atlantic Oceans. It was first described by Gray in 1872 from a specimen recovered in northern Australia—hence the inappropriate specific name tropicalis.

<span class="mw-page-title-main">Guadalupe fur seal</span> Species of carnivore

The Guadalupe fur seal is one of eight members of the fur seal genus Arctocephalus. They are the northernmost member of this genus. Sealers reduced the population to just a few dozen by the late 19th century, but the species had recovered to 10,000 in number by the late 1990s. Many individuals can be found on Mexico's Guadalupe Island.

<span class="mw-page-title-main">Juan Fernández fur seal</span> Species of carnivore

The Juan Fernández fur seal is the second smallest of the fur seals, second only to the Galápagos fur seal. They are found only on the Pacific Coast of South America, more specifically on the Juan Fernández Islands and the Desventuradas Islands. There is still much that is unknown about this species. Scientists still do not know the average life span of this species, or the diet and behavior of males apart from the breeding season.

<span class="mw-page-title-main">Galápagos fur seal</span> Species of carnivore

The Galápagos fur seal is one of eight seals in the genus Arctocephalus. It is the smallest of all eared seals. It is endemic to the Galápagos Islands in the eastern Pacific. The total estimated population as of 1970 was said to be about 30,000, although the population has been said to be on the decline since the 1980s due to environmental factors such as pollution, disease, invasive species, and their limited territory. Due to the population having been historically vulnerable to hunting, the Galápagos fur seal has been protected by the Ecuadorian government since 1934

<span class="mw-page-title-main">South American sea lion</span> Species of carnivore

The South American sea lion, also called the southern sea lion and the Patagonian sea lion, is a sea lion found on the western and southeastern coasts of South America. It is the only member of the genus Otaria. The species is highly sexually dimorphic. Males have a large head and prominent mane. They mainly feed on fish and cephalopods and haul out on sand, gravel, rocky, or pebble beaches. In most populations, breeding males are both territorial and harem holding; they establish territories first and then try to herd females into them. The overall population of the species is considered stable, estimated at 265,000 animals.

<span class="mw-page-title-main">Australian sea lion</span> Species of carnivore

The Australian sea lion, also known as the Australian sea-lion or Australian sealion, is a species of sea lion that is the only endemic pinniped in Australia. It is currently monotypic in the genus Neophoca, with the extinct Pleistocene New Zealand sea lion Neophoca palatina the only known congener. With a population estimated at 14,730 animals, the Wildlife Conservation Act of Western Australia (1950) has listed them as "in need of special protection". Their Conservation status is listed as endangered. These pinnipeds are specifically known for their abnormal breeding cycles, which are varied between a 5-month breeding cycle and a 17-18 month aseasonal breeding cycle, compared to other pinnipeds which fit into a 12-month reproductive cycle. Females are either silver or fawn with a cream underbelly and males are dark brown with a yellow mane and are bigger than the females.

<i>Arctocephalus forsteri</i> Species of carnivore

Arctocephalus forsteri is a species of fur seal found mainly around southern Australia and New Zealand. The name New Zealand fur seal is used by English speakers in New Zealand; kekeno is used in the Māori language. As of 2014, the common name long-nosed fur seal has been proposed for the population of seals inhabiting Australia.

<span class="mw-page-title-main">South American fur seal</span> Species of mammal

The South American fur seal breeds on the coasts of Peru, Chile, the Falkland Islands, Argentina, Uruguay and Brazil. The total population is around 250,000. However, population counts are sparse and outdated. Although Uruguay has long been considered to be the largest population of South American fur seals, recent census data indicates that the largest breeding population of A. a. australis are at the Falkland Islands followed by Uruguay. The population of South American fur seals in 1999 was estimated at 390,000, a drop from a 1987 estimate of 500,000 - however a paucity of population data, combined with inconsistent census methods, makes it difficult to interpret global population trends.

<span class="mw-page-title-main">Argonauta nodosa</span> Species of mollusc

Argonauta nodosus [previously known as Argonauta nodosa], also known as the knobby or knobbed argonaut, is a species of pelagic octopus. The female of the species, like all argonauts, creates a paper-thin eggcase that coils around the octopus much like the way a nautilus lives in its shell. The shell is usually approximately 150 mm in length, although it can exceed 250 mm in exceptional specimens; the world record size is 292.0 mm. A. nodosus produces a very characteristic shell, which is covered in many small nodules on the ridges across the shell, hence the specific epithet nodosus and common name. These nodules are less obvious or even absent in juvenile females, especially those under 5 cm in length. All other argonaut species have smooth ridges across the shell walls.

<span class="mw-page-title-main">Puffadder shyshark</span> Species of shark

The puffadder shyshark, also known as the Happy Eddie, is a species of catshark, belonging to the family Scyliorhinidae, endemic to the temperate waters off the coast of South Africa. This common shark is found on or near the bottom in sandy or rocky habitats, from the intertidal zone to a depth of 130 m (430 ft). Typically reaching 60 cm (24 in) in length, the puffadder shyshark has a slender, flattened body and head. It is strikingly patterned with a series of dark-edged, bright orange "saddles" and numerous small white spots over its back. The Natal shyshark, formally described in 2006, was once considered to be an alternate form of the puffadder shyshark.

<i>Enteroctopus magnificus</i> Species of mollusc

Enteroctopus magnificus, also known as the southern giant octopus, is a large octopus in the genus Enteroctopus. It is native to the waters off Namibia and South Africa.

<i>Cynoglossus capensis</i> Species of fish

Cynoglossus capensis, commonly known as the sand tonguesole, is a species of tonguefish.

References

  1. ↑ Hofmeyr, G.J.G. (2015). "Arctocephalus pusillus". IUCN Red List of Threatened Species . 2015: e.T2060A45224212. doi: 10.2305/IUCN.UK.2015-4.RLTS.T2060A45224212.en . Retrieved 12 November 2021.
  2. ↑ "Appendices | CITES". cites.org. Retrieved 14 January 2022.
  3. 1 2 3 4 5 6 7 8 9 Randall R. Reeves; Brent S. Stewart; Phillip J. Clapham; James A. Powell (2002). National Audubon Society Guide to Marine Mammals of the World. Alfred A. Knopf, Inc. ISBN   0-375-41141-0.
  4. ↑ "The S.A. Fur Seal". Botany.uwc.ac.za. 1 February 2001. Archived from the original on 1 July 2014. Retrieved 13 April 2013.
  5. 1 2 3 4 5 6 7 8 King, J. (1983). Seals of the World. Ithaca, New York: Comstock Publishing Associates.
  6. ↑ Arnould, John P.Y.; Hindell, Mark A. (2001). "Dive behaviour, foraging location... preview & related info". Canadian Journal of Zoology. 79: 35–48. doi:10.1139/cjz-79-1-35. hdl: 10536/DRO/DU:30015951 . Archived from the original on 16 February 2013. Retrieved 13 April 2013.
  7. 1 2 3 4 Schliemann, H. (1990). "Eared Seals and Walruses". In Grzimek, B. (ed.). Grzimek's Encyclopedia of Mammals. New York: McGraw-Hill. pp. 168–203.
  8. ↑ Smithsonian Magazine; Nuwer, Rachel. "Fur Seals Caught Preying on Sharks Off South Africa". Smithsonian Magazine.
  9. 1 2 3 4 5 6 Riedman, M. (1990). The Pinnipeds: Seals, Sea Lions, and Walruses. Berkeley: University of California Press.
  10. ↑ Penry, Gwenith S.; Baartman, Ashwynn C.; Bester, Marthán N. (2013). "Vagrant elephant seal predation on Cape fur seal pups, Plettenberg Bay, South Africa". Polar Biology. 36 (9): 1381–1383. Bibcode:2013PoBio..36.1381P. doi:10.1007/s00300-013-1350-4. S2CID   20350457.
  11. ↑ "Beach lions again hunting seals and coastal birds in Namibia, after 35 years". 29 January 2019.
  12. ↑ Palermo (2015). "Gruesome Meal: Seagulls Snack on Baby Seals' Eyeballs". Live Science.
  13. ↑ "Anti-Predatory Strategies of Cape Fur Seals at Seal Island". www.elasmo-research.org.
  14. ↑ Tripovich, J.S.; Canfield, R.; Rogers, T.L.; Arnould, J.P.Y. (2008). "Characterisation of Australian fur seal vocalizations during the breeding season". Marine Mammal Science. 24 (4): 913–928. Bibcode:2008MMamS..24..913T. doi:10.1111/j.1748-7692.2008.00229.x.
  15. ↑ Tripovich, J.S.; Rogers, T.L.; Canfield, R.; Arnould, J.P.Y (2006). "Individual variation in the pup attraction call produced by female Australian fur seals during early lactation" (PDF). Journal of the Acoustical Society of America. 120 (1): 502–509. Bibcode:2006ASAJ..120..502T. doi:10.1121/1.2202864. hdl: 10536/DRO/DU:30009058 . PMID   16875246.
  16. ↑ Tripovich, J.S.; Canfield, R.; Rogers, T.L.; Arnould, J.P.Y. (2009). "Individual variation of the Female Attraction Call produced by Australian fur seal pups throughout the maternal dependence period". Bioacoustics. 18 (3): 259–276. Bibcode:2009Bioac..18..259T. doi:10.1080/09524622.2009.9753605. S2CID   76654284.
  17. ↑ Tripovich, J.S.; Rogers, T.L.; Dutton, G. (2009). "Faecal testosterone concentrations and the acoustic behavior of two male captive Australian fur seals". Australian Mammalogy. 31 (2): 117–122. doi:10.1071/AM09009.
  18. ↑ Tripovich, J.S.; Rogers, T.L.; Arnould, J.P.Y. (2005). "Species-specific characteristics and individual variation of the Bark Call produced by male Australian fur seals (Arctocephalus pusillus doriferus)" (PDF). Bioacoustics. 15 (1): 502–509. Bibcode:2005Bioac..15...79T. doi:10.1080/09524622.2005.9753539. hdl: 10536/DRO/DU:30008864 . S2CID   83645557.
  19. ↑ Tripovich, J.S.; Charrier, I.; Rogers, T.L.; Canfield, R.; Arnould, J.P.Y. (2008). "Acoustic features involved in the neighbour-stranger vocal recognition process in male Australian fur seals". Behavioural Processes. 79 (1): 74–80. doi:10.1016/j.beproc.2008.04.007. PMID   18571339. S2CID   727101.
  20. ↑ Tripovich, J.S.; Charrier, I.; Rogers, T.L.; Canfield, R.; Arnould, J.P.Y. (2008). "Who goes there? The dear-enemy effect in male Australian fur seals (Arctocephalus pusillus doriferus)". Marine Mammal Science. 24 (4): 941–948. doi:10.1111/j.1748-7692.2008.00222.x.
  21. ↑ Tripovich, Joy S.; Rogers, Tracey L.; Arnould, John P.Y. (2005). "SPECIES-SPECIFIC CHARACTERISTICS AND INDIVIDUAL VARIATION OF THE BARK CALL PRODUCED BY MALE AUSTRALIAN FUR SEALS, ARCTOCEPHALUS PUSILLUS DORIFERUS". Bioacoustics. 15 (1): 79–96. Bibcode:2005Bioac..15...79T. doi:10.1080/09524622.2005.9753539. ISSN   0952-4622. S2CID   83645557.
  22. ↑ "Aggressive fur seals attacking rare birds, pelicans and fishing nets, SA fishermen warn". 891 ABC Adelaide. 24 April 2015. Retrieved 24 April 2015.
  23. ↑ "South African and Australian Fur Seals (Arctocephalus pusillus)". www.pinnipeds.org.
  24. ↑ Town, Jane Flanagan, Cape. "Seals driven mad by eating toxic fish attack Cape Town bathers". The Times . ISSN   0140-0460 . Retrieved 3 February 2023.{{cite news}}: CS1 maint: multiple names: authors list (link)
  25. ↑ What's behind South Africa's rise in seal attacks?, France 24, 20 January 2023
  26. 1 2 Curtis, S.; Elwen, S. H.; Dreyer, N.; Gridley, T. (19 October 2021). "Entanglement of Cape fur seals (Arctocephalus pusillus pusillus) at colonies in central Namibia". Marine Pollution Bulletin. 171: 112759. Bibcode:2021MarPB.17112759C. doi:10.1016/j.marpolbul.2021.112759. PMID   34364137 – via PubMed.
  27. ↑ "Plastics and pusillus - Investigating the impact of plastic pollution on Cape Fur Seals (Arctocephalus pusillus pusillus) at colonies in central Namibia" (PDF). Retrieved 5 August 2023.
  28. ↑ "Namibia's seal saviour: How one man is freeing hundreds of animals from deadly debris". Beautiful News. 28 November 2019.
  29. ↑ "The Havoc Of Climate Change Claimed The Lives Of Thousands Of Seals In Namibia". 16 November 2020.
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