Subantarctic fur seal: Difference between revisions
Content deleted Content added
m Tagging pages with bare URLs for citation, prior to follow up with tools (via WP:JWB) |
Citation bot (talk | contribs) Add: date, website, title. Changed bare reference to CS1/2. | Use this bot. Report bugs. | Suggested by Spinixster | Category:Arctocephalus | #UCB_Category 4/9 |
||
| Line 21: | Line 21: | ||
== Description == |
== Description == |
||
The [[subantarctic]] fur seal is medium in size compared with other [[fur seals]]. Males grow to 2{{nbsp}}m and 160 kg, whereas females are substantially smaller—1.4{{nbsp}}m and 50 kg. Both sexes are strongly [[sexual dimorphism|sexually dimorphic]], with creamy-orange chests and faces. Their bellies are more brownish. Males have a dark grey to black back, while females are a lighter grey. Males have a characteristic dark tuft of hair on the top of their head that stands erect when they are excited.<ref>https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal |
The [[subantarctic]] fur seal is medium in size compared with other [[fur seals]]. Males grow to 2{{nbsp}}m and 160 kg, whereas females are substantially smaller—1.4{{nbsp}}m and 50 kg. Both sexes are strongly [[sexual dimorphism|sexually dimorphic]], with creamy-orange chests and faces. Their bellies are more brownish. Males have a dark grey to black back, while females are a lighter grey. Males have a characteristic dark tuft of hair on the top of their head that stands erect when they are excited.<ref>{{cite web | url=https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal | title=Subantarctic Fur Seal }}</ref> Pups are black at birth, but molt at about 3 months old. The snout is short and flat, and the flippers are short and broad.<ref>{{Cite book |title=Subantarctic Fur Seal: Arctocephalus tropicalis |url=https://www.sciencedirect.com/science/article/pii/B9780128043271002521 |archive-date=2021-05-07 |access-date=2021-05-07 |website=Encyclopedia of Marine Mammals (Third Edition) 2018, Pages 957-960|date=January 2018 |pages=957–960 |publisher=Academic Press |doi=10.1016/B978-0-12-804327-1.00252-1 |isbn=9780128043271 }}</ref> Subantarctic fur seals live for about 20–25 years. |
||
== Distribution == |
== Distribution == |
||
| Line 27: | Line 27: | ||
Subantarctic fur seals are geographically widespread. As their name implies, they generally breed in more northerly locations than the [[Antarctic fur seal]]s. The largest breeding colonies are on [[Gough Island]] in the South Atlantic and [[Île Amsterdam]] in the southern part of the Indian Ocean. Breeding grounds are also found at Marion Island in the [[Prince Edward Islands]] (where an overlap with Antarctic fur seals occurs), the [[Crozet Islands]], and [[Macquarie Island]]. Where grounds overlap, the subantarctic species can be identified by the orange colour on the chest. |
Subantarctic fur seals are geographically widespread. As their name implies, they generally breed in more northerly locations than the [[Antarctic fur seal]]s. The largest breeding colonies are on [[Gough Island]] in the South Atlantic and [[Île Amsterdam]] in the southern part of the Indian Ocean. Breeding grounds are also found at Marion Island in the [[Prince Edward Islands]] (where an overlap with Antarctic fur seals occurs), the [[Crozet Islands]], and [[Macquarie Island]]. Where grounds overlap, the subantarctic species can be identified by the orange colour on the chest. |
||
About 300,000 subantarctic fur seals are alive today, probably substantially down from when they were first discovered in 1810, as they were hunted for their pelts throughout the 19th century. Populations are recovering rapidly, though, in most areas whilst under the protection of the [[Convention for the Conservation of Antarctic Seals]]. A small population on [[Heard Island]] is endangered. Unlike the Antarctic fur seal, whose genetic variation is low due to hunting making all but one breeding colony extinct by 1900, the diversity amongst subantarctic specimens remains high.<ref>{{Cite web |title=Subantarctic Fur Seal conservation status |url=https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal |archive-date=2021-05-07 |access-date=2021-05-07 |website=Seal Conservation Society}}</ref> There appears to be 3 distinct genetic lineages in the species, with none of them representing any particular geographic area.<ref>https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal |
About 300,000 subantarctic fur seals are alive today, probably substantially down from when they were first discovered in 1810, as they were hunted for their pelts throughout the 19th century. Populations are recovering rapidly, though, in most areas whilst under the protection of the [[Convention for the Conservation of Antarctic Seals]]. A small population on [[Heard Island]] is endangered. Unlike the Antarctic fur seal, whose genetic variation is low due to hunting making all but one breeding colony extinct by 1900, the diversity amongst subantarctic specimens remains high.<ref>{{Cite web |title=Subantarctic Fur Seal conservation status |url=https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal |archive-date=2021-05-07 |access-date=2021-05-07 |website=Seal Conservation Society}}</ref> There appears to be 3 distinct genetic lineages in the species, with none of them representing any particular geographic area.<ref>{{cite web | url=https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal | title=Subantarctic Fur Seal }}</ref> |
||
==Behavior== |
==Behavior== |
||
===Breeding=== |
===Breeding=== |
||
[[File:Arctocephalus tropicalis an injured male resting in the grass.JPG|thumb|left|upright=1.1|Male subantarctic fur seal with injuries from a recent fight with another male]] |
[[File:Arctocephalus tropicalis an injured male resting in the grass.JPG|thumb|left|upright=1.1|Male subantarctic fur seal with injuries from a recent fight with another male]] |
||
As with other otariids, subantarctic fur seals gather in large [[Rookery|rookeries]] on the shore to breed. They have a [[Polygyny|polygynous]] mating system in which dominant males will defend their harem of 6-20 females. Fights between males for mating rights are violent and can result in severe injuries. Apart from physically fighting, males will also compete against each other through vocalizations and threat displays.<ref>https://animaldiversity.org/accounts/Arctocephalus_tropicalis/ |
As with other otariids, subantarctic fur seals gather in large [[Rookery|rookeries]] on the shore to breed. They have a [[Polygyny|polygynous]] mating system in which dominant males will defend their harem of 6-20 females. Fights between males for mating rights are violent and can result in severe injuries. Apart from physically fighting, males will also compete against each other through vocalizations and threat displays.<ref>{{cite web | url=https://animaldiversity.org/accounts/Arctocephalus_tropicalis/ | title=Arctocephalus tropicalis (Subantarctic fur seal) | website=[[Animal Diversity Web]] }}</ref> The breeding season takes place from November to January. For females, gestation lasts around 51 weeks, at the end of which they will give birth to a single pup. 8-12 days after giving birth, they will breed again. Males are capable of mating at around 3-4 years of age, but they are unlikely to be able to hold a harem until they are 10-11 years old. Females reach sexual maturity at around 5 years.<ref name=animalia>{{cite web|url=https://animalia.bio/subantarctic-fur-seal|title=Subantarctic fur sea|publisher=Animalia|access-date=2023-05-31}}{{better source needed|reason=Animalia lists Wikipedia as a reference|date=May 2023}}</ref> |
||
===Life cycle=== |
===Life cycle=== |
||
After being born, pups spend around 11 months feeding on their mother's milk, which contains around 39% fat. They stay at the rookery during this period. Weaning occurs shortly before the next offspring is born. They molt their black coat at around 3 months of age. As adults, they continue to molt their coat annually between March and May.<ref name=animalia/><ref>https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal |
After being born, pups spend around 11 months feeding on their mother's milk, which contains around 39% fat. They stay at the rookery during this period. Weaning occurs shortly before the next offspring is born. They molt their black coat at around 3 months of age. As adults, they continue to molt their coat annually between March and May.<ref name=animalia/><ref>{{cite web | url=https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal | title=Subantarctic Fur Seal }}</ref> |
||
===Diet and foraging=== |
===Diet and foraging=== |
||
Subantarctic fur seals hunt in shallow waters at night, when [[lanternfish|myctophid]] fish come close to the surface. They also feed on [[squid]].<ref>http://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal |
Subantarctic fur seals hunt in shallow waters at night, when [[lanternfish|myctophid]] fish come close to the surface. They also feed on [[squid]].<ref>{{cite web | url=http://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal | title=Subantarctic Fur Seal }}</ref> Other prey can include crustaceans, and occasionally [[Rockhopper penguin|rockhopper penguins]] and other [[seabird|seabirds]].<ref>{{cite web | url=https://www.animalia.bio/subantarctic-fur-seal#:~:text=Diet%20and%20Nutrition,Rockhopper%20penguins%20and%20sea%20birds. | title=Subantarctic Fur Seal - Facts, Diet, Habitat & Pictures on Animalia.bio }}</ref> |
||
===Travelling=== |
===Travelling=== |
||
Subantarctic fur seals are unique in their tendency to occasionally travel very long distances from their home islands. Young males have been seen travelling thousands of miles from their native habitat. In July 2015, a young male seal was caught and later released by local fishermen off the coast of Kenya, more than 4,000 miles (6.400km) from its home. This is the furthest north that a subantarctic fur seal has been recorded travelling to.<ref>https://blog.nature.org/2015/07/22/this-fur-seal-is-4000-miles-from-home-heres-why/ |
Subantarctic fur seals are unique in their tendency to occasionally travel very long distances from their home islands. Young males have been seen travelling thousands of miles from their native habitat. In July 2015, a young male seal was caught and later released by local fishermen off the coast of Kenya, more than 4,000 miles (6.400km) from its home. This is the furthest north that a subantarctic fur seal has been recorded travelling to.<ref>{{cite web | url=https://blog.nature.org/2015/07/22/this-fur-seal-is-4000-miles-from-home-heres-why/ | title=This Fur Seal is 4,000 Miles from Home. Here's Why | date=22 July 2015 }}</ref> Lactating females have been seen travelling up to 530km from their colonies in order to forage for food.<ref>{{cite web | url=https://www.pinnipeds.org/seal-information/species-information-pages/sea-lions-and-fur-seals/subantarctic-fur-seal#:~:text=Lactating%20female%20Subantarctic%20fur%20seals,is%20expected%20to%20be%20greater. | title=Subantarctic Fur Seal }}</ref> |
||
[[File:Arctocephalus tropicalis en playa de El Fortín, Uruguay.jpg|thumb|upright=1.05|A male resting on a beach in playa de El Fortin, [[Uruguay]], having travelled far from its native area]] |
[[File:Arctocephalus tropicalis en playa de El Fortín, Uruguay.jpg|thumb|upright=1.05|A male resting on a beach in playa de El Fortin, [[Uruguay]], having travelled far from its native area]] |
||
Revision as of 05:06, 25 June 2023
| Subantarctic fur seal | |
|---|---|
| |
| Male | |
| |
| Female | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Carnivora |
| Clade: | Pinnipedia |
| Family: | Otariidae |
| Genus: | Arctocephalus |
| Species: | A. tropicalis
|
| Binomial name | |
| Arctocephalus tropicalis Gray, 1872
| |
| |
| Subantarctic fur seal range | |
The subantarctic fur seal (Arctocephalus tropicalis) is found in the southern parts of the Indian, Pacific, and Atlantic Oceans.[3] It was first described by Gray in 1872 from a specimen recovered in northern Australia—hence the inappropriate specific name tropicalis.[4]
Description
The subantarctic fur seal is medium in size compared with other fur seals. Males grow to 2 m and 160 kg, whereas females are substantially smaller—1.4 m and 50 kg. Both sexes are strongly sexually dimorphic, with creamy-orange chests and faces. Their bellies are more brownish. Males have a dark grey to black back, while females are a lighter grey. Males have a characteristic dark tuft of hair on the top of their head that stands erect when they are excited.[5] Pups are black at birth, but molt at about 3 months old. The snout is short and flat, and the flippers are short and broad.[6] Subantarctic fur seals live for about 20–25 years.
Distribution
Subantarctic fur seals are geographically widespread. As their name implies, they generally breed in more northerly locations than the Antarctic fur seals. The largest breeding colonies are on Gough Island in the South Atlantic and Île Amsterdam in the southern part of the Indian Ocean. Breeding grounds are also found at Marion Island in the Prince Edward Islands (where an overlap with Antarctic fur seals occurs), the Crozet Islands, and Macquarie Island. Where grounds overlap, the subantarctic species can be identified by the orange colour on the chest.
About 300,000 subantarctic fur seals are alive today, probably substantially down from when they were first discovered in 1810, as they were hunted for their pelts throughout the 19th century. Populations are recovering rapidly, though, in most areas whilst under the protection of the Convention for the Conservation of Antarctic Seals. A small population on Heard Island is endangered. Unlike the Antarctic fur seal, whose genetic variation is low due to hunting making all but one breeding colony extinct by 1900, the diversity amongst subantarctic specimens remains high.[7] There appears to be 3 distinct genetic lineages in the species, with none of them representing any particular geographic area.[8]
Behavior
Breeding
As with other otariids, subantarctic fur seals gather in large rookeries on the shore to breed. They have a polygynous mating system in which dominant males will defend their harem of 6-20 females. Fights between males for mating rights are violent and can result in severe injuries. Apart from physically fighting, males will also compete against each other through vocalizations and threat displays.[9] The breeding season takes place from November to January. For females, gestation lasts around 51 weeks, at the end of which they will give birth to a single pup. 8-12 days after giving birth, they will breed again. Males are capable of mating at around 3-4 years of age, but they are unlikely to be able to hold a harem until they are 10-11 years old. Females reach sexual maturity at around 5 years.[10]
Life cycle
After being born, pups spend around 11 months feeding on their mother's milk, which contains around 39% fat. They stay at the rookery during this period. Weaning occurs shortly before the next offspring is born. They molt their black coat at around 3 months of age. As adults, they continue to molt their coat annually between March and May.[10][11]
Diet and foraging
Subantarctic fur seals hunt in shallow waters at night, when myctophid fish come close to the surface. They also feed on squid.[12] Other prey can include crustaceans, and occasionally rockhopper penguins and other seabirds.[13]
Travelling
Subantarctic fur seals are unique in their tendency to occasionally travel very long distances from their home islands. Young males have been seen travelling thousands of miles from their native habitat. In July 2015, a young male seal was caught and later released by local fishermen off the coast of Kenya, more than 4,000 miles (6.400km) from its home. This is the furthest north that a subantarctic fur seal has been recorded travelling to.[14] Lactating females have been seen travelling up to 530km from their colonies in order to forage for food.[15]
References
- ^ Hofmeyr, G.J.G. (2015). "Arctocephalus tropicalis". IUCN Red List of Threatened Species. 2015: e.T2062A45224547. doi:10.2305/IUCN.UK.2015-4.RLTS.T2062A45224547.en. Retrieved 12 November 2021.
- ^ "Appendices | CITES". cites.org. Retrieved 2022-01-14.
- ^ "Subantarctic Fur Seals behaviour". The MarineBio Conservation Society. 18 May 2017. Retrieved 2021-05-07.
{{cite web}}:|archive-date=requires|archive-url=(help) - ^ https://www.itis.gov/servlet/SingleRpt/RefRpt?search_topic=Scientific_Author&search_value=%28J.+E.+Gray%2C+1872%29 [bare URL]
- ^ "Subantarctic Fur Seal".
- ^ Subantarctic Fur Seal: Arctocephalus tropicalis. Academic Press. January 2018. pp. 957–960. doi:10.1016/B978-0-12-804327-1.00252-1. ISBN 9780128043271. Retrieved 2021-05-07.
{{cite book}}:|archive-date=requires|archive-url=(help);|website=ignored (help) - ^ "Subantarctic Fur Seal conservation status". Seal Conservation Society. Retrieved 2021-05-07.
{{cite web}}:|archive-date=requires|archive-url=(help) - ^ "Subantarctic Fur Seal".
- ^ "Arctocephalus tropicalis (Subantarctic fur seal)". Animal Diversity Web.
- ^ a b "Subantarctic fur sea". Animalia. Retrieved 2023-05-31.[better source needed]
- ^ "Subantarctic Fur Seal".
- ^ "Subantarctic Fur Seal".
- ^ "Subantarctic Fur Seal - Facts, Diet, Habitat & Pictures on Animalia.bio".
- ^ "This Fur Seal is 4,000 Miles from Home. Here's Why". 22 July 2015.
- ^ "Subantarctic Fur Seal".
Further reading
- Wynen, Louise P. et al. "Postsealing genetic variation and population structure of two species of fur seal (Arctocephalus gazella and A. tropicalis)". Molecular Ecology. Vol. 9. (2000). pp. 299–314.
- "Arctocephalus tropicalis". Integrated Taxonomic Information System. Retrieved 24 January 2006.
- 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.
Categories:
- Articles with bare URLs for citations from June 2023
- IUCN Red List least concern species
- Arctocephalus
- Pinnipeds of Africa
- Pinnipeds of South America
- Fauna of subantarctic islands
- Mammals of Argentina
- Mammals of Chile
- Pinnipeds of Australia
- Mammals of New South Wales
- Mammals of Victoria (state)
- Mammals of Western Australia
- Fauna of Gough Island
- Fauna of Heard Island and McDonald Islands
- Fauna of the Prince Edward Islands
- Île Amsterdam
- Mammals described in 1872
- Taxa named by John Edward Gray
- Carnivorans of Africa
- Carnivorans of South America
- Least concern biota of South America