Dusicyon australis

Geographic Range

Falkland Islands wolves, Dusicyon australis , also known as warrah , are found only on the Falkland Islands, an archipelago off the coast of southern South America. Their closest living relative, Chrysocyon brachyurus , is found on the mainland of South America.

• Biogeographic Regions
• neotropical neotropical
  • native native

• Other Geographic Terms
• island endemic island endemic

Habitat

Falkland Islands wolves lived on both the east and west sides of the islands. They inhabit rocky mountainous terrain or boggy plains and beaches. They were reportedly seen swimming while foraging along the beaches. These wolves apparently occupied burrows in the sand-hills. A finding in 2010 seems to confirm this: teeth and skulls of D. australis were found in a collapsed burrow in the Falkland Islands. Researchers speculate that D. australis did not dig the burrows but rather lived in burrows made by penguins or other animals.

• Habitat Regions
• temperate temperate
• terrestrial terrestrial

• Terrestrial Biomes
• savanna or grassland savanna or grassland

• Aquatic Biomes
• coastal coastal

• Wetlands
• bog bog

Physical Description

Falkland Islands wolves were medium-sized, bulky, and fox-like. The legs were short, as was their tails. When they were standing, the tail typically did not reach the ground. The coat was thick, with mixtures of tawny, tan, and black hairs dorsally; the coat became paler ventrally. The neck and inner legs were white. They had relatively small pinnae. The bushy tail was brown in the middle and had a distinctively white tip. Falkland Islands wolves had a mixture of fox and wolf traits that caused them to resemble no other living canid : according to Darwin, "all maintain that no such animal is found in any part of South America" (Darwin, 1839).

The dentition included very large carnassials, notable since their closest living relative, Chrysocyon brachyurus , has greatly reduced carnassials. The carnassials had a protocone that pointed nearly backwards (Osgood, 1934). The skull contained a high arching, expanded frontal bone and no interparietal crest (Clutton-Brock, 1977).

Falkland Islands wolves were the size of large foxes, with an average head-body length of 97 cm. Height at the shoulder was 38.1 cm. The tail was between 28.5 and 33 cm long. Mass is unknown.

• Other Physical Features
• endothermic endothermic
• homoiothermic
• bilateral symmetry bilateral symmetry

Reproduction

There is no information available about the mating systems of Falkland Islands wolves. It is possible that its mating system was similar to that of its closest relative, Chrysocyon brachyurus , which is monogamous. The two species, however, differ greatly in appearance and behavior, as they diverged 6.7 million years ago, and mating systems may not be alike at all (Slater et al, 2009).

There is no information available about reproduction of Falkland Islands wolves.

• Key Reproductive Features
• iteroparous iteroparous
• gonochoric/gonochoristic/dioecious (sexes separate)
• sexual sexual
• viviparous viviparous

Little is known of the parental investment of D. australis . One contemporary account relates the capture of three wolves from a burrow: two cubs with an older male (Falkland Islands Museum and National Trust, 2012). Additionally, in 2010 a burrow with four Falkland Islands wolf skulls, including a juvenile, was discovered. These observations and findings suggest that D. australis might have had parental habits similar to those of other canids who raise young in burrows, such as Vulpes vulpes and Lycaon pictus (Renshaw, 1905).

• Parental Investment
• altricial altricial
• female parental care female parental care
• pre-fertilization
  • provisioning
  • protecting
    • female
• pre-hatching/birth
  • provisioning
    • female
  • protecting
    • female
• pre-weaning/fledging
  • provisioning
    • female

Lifespan/Longevity

There is no information available on the lifespan of Falkland Islands wolves.

Behavior

Some interactions between Falkland Islands wolves and humans were documented. Darwin noted their particularly gentle nature, they did not seem to fear humans. The only mammal native to the Falkland Islands, these wolves showed traits of "tameness and curiosity" (Darwin) toward human visitors to the islands. Some wolves were reportedly domesticated by inhabitants of the islands in the 1800s (Clutton-Brock, 1977). Unfortunately, this unusual tameness was used to their disadvantage: as Darwin notes, men "frequently killed them in the evening, by holding out a piece of meat in one hand, and in the other a knife ready to stick them."

Little else is known about Falkland Islands wolf behavior. This species is extinct; the only observations of living individuals come from 19th century primary accounts, of which there are few. Nineteenth century naturalist Hamilton Smith reported that D. australis had a "feeble bark" and was active during the day. They hunted alone, not in packs (Renshaw, 1905). The burrows in which the wolves likely slept and raised young were sometimes interconnected (Renshaw, 1905), implying intraspecific social interactions. Hamilton Smith noted that the wolves were "social" despite their hunting habits.

• Key Behaviors
• terricolous
• diurnal diurnal
• motile motile
• sedentary sedentary
• social social

Home Range

There is no information about home range behavior, although it was confined to either the western or eastern half of the Falkland Islands.

Communication and Perception

Hamilton Smith reported that Dusicyon australis tended not to vocalize often but sometimes its cries could be heard at night. In addition, after settlers colonized the islands, the wolves began to "learn a kind of barking." Little is known about their intraspecific social habits.

• Communication Channels
• acoustic acoustic

• Perception Channels
• visual visual
• tactile tactile
• acoustic acoustic
• chemical chemical

Food Habits

As there were no other mammals present on the Falkland Islands, Dusicyon australis preyed upon birds (especially geese and penguins ), small invertebrates, and pinnipeds that they would catch on the shores. In addition, Hamilton Smith reported that these wolves would eat "fish, crabs, limpets, lizards, toads, serpents, and insects."

• Primary Diet
• carnivore carnivore
  • eats terrestrial vertebrates
  • eats non-insect arthropods

• Animal Foods
• birds
• mammals
• amphibians
• reptiles
• insects
• mollusks
• aquatic crustaceans

Predation

Dusicyon australis was the top predator in its habitat and faced no natural predation until the colonization of the Falkland Islands by humans.

Ecosystem Roles

Dusicyon austalis was the dominant predator in the Falkland Islands.

Economic Importance for Humans: Positive

According to Hamilton Smith, the settlers of the islands reportedly domesticated some Falkland Islands wolves, although to what extent the animals were tamed is unknown. In addition, hunters killed these wolves for their fur, which was sold in the fur trade. The fur in particular ended up in New York at “the fur stores of Mr G Astor" (Hamilton Smith, 1839), who amassed a large number of Falkland Island wolf pelts.

• Positive Impacts
• body parts are source of valuable material

Economic Importance for Humans: Negative

Although Dusicyon australis did not often represent a threat toward humans because of its relative tameness, there were scattered reports of wolf attacks on humans. These wolves may have represented a threat to livestock, although naturalist Graham Renshaw argued that this fear was unsubstantiated (Renshaw, 1905). Nonetheless, the wolf was hunted to extinction by settlers for this reason as well as for its fur.

• Negative Impacts
• injures humans
  • bites or stings

Conservation Status

Dusicyon australis is extinct. During the 1800's, the species was already in decline due to human settlers, who killed these wolves for their fur and to protect livestock. By 1839 Astor's fur hunters had greatly reduced the number of wolves on the islands (Hamilton Smith, 1839). By the end of the 19th century, they were extinct, with the final member of the species killed most likely in 1876.

Other Comments

Dusicyon australis has presented scientists with a mystery ever since its discovery. Many zoologists have wondered how only one mammal species managed to arrive on the Falkland Islands. However, because they are extinct, specimens are rare. Although Hamilton Smith reported numerous pelts in a New York fur store, these furs have not been found. Only 11 specimens have been preserved and very few with skins. Some scientists suggest that these wolves were brought by humans to the islands in the last 10,000 years, noting that they share many traits with domesticated dogs, such as a white tail tip and a larger frontal bone (Clutton-Brock, 1977). A 2009 study by Slater et al. used molecular dating to determine that the Falkland Islands wolf lineage dated to 330,000 years ago, long before humans arrived in South America (Slater et al, 2009). In addition, the study found that Dusicyon australis is most closely related to maned wolves ( Chrysocyon brachyurus ) and diverged about 6.7 mya. They suggested that Dusicyon australis might have reached the Falkland Islands "by rafting or dispersing over glacial ice during the late Pleistocene."

Dusicyon austalis may have been several species. Darwin reported that wolves living on the eastern and western sides of the archipelago looked slightly different and were possible separate species. Western Falkland Island wolves were typically smaller, with white feet and a longer tail (Hamilton Smith, 1839).

Dusicyon australis was formerly known as Antarctic wolves, Canis antarcticus .

Additional Links

Encyclopedia of Life

Contributors

Katherine Oshman (author), Yale University, Eric Sargis (editor), Yale University, Rachel Racicot (editor), Yale University, Tanya Dewey (editor), University of Michigan-Ann Arbor.

References

CIA, 2012. "CIA - The World Factbook" (On-line). Accessed April 07, 2012 at https://www.cia.gov/library/publications/the-world-factbook/geos/fk.html .

Cabrera, A. 1931. On Some South American Canine Genera. Journal of Mammalogy , 12/1: 54-67. Accessed February 15, 2012 at http://www.jstor.org/stable/1373806 .

Clutton-Brock, J. 1977. Man-Made Dogs. Science , 197: 1340-1342. Accessed April 08, 2012 at http://www.ncbi.nlm.nih.gov/pubmed/17746990 .

Darwin, C. 1839. Narrative of the surveying voyages of His Majesty's Ships Adventure and Beagle between the years 1826 and 1836, describing their examination of the southern shores of South America, and the Beagle's circumnavigation of the globe. Journal and remarks. 1832-1836 . London: Henry Colburn. Accessed February 15, 2012 at http://darwin-online.org.uk/content/frameset?viewtype=text&itemID=F10.3&pageseq=268 .

Falkland Islands Museum and National Trust, 2012. "The Evans Warrah" (On-line). Accessed April 09, 2012 at http://www.falklands-museum.com/index.php?option=com_content&view=article&id=179&Itemid=261 .

Hamilton Smith, C. 1843. Mammalia: Dogs . London: Edinburgh.

Hamilton Smith, C. 1839. The natural history of dogs: Canidae or genus canis of authors. Including also the genera hyaena and proteles, Volume 9 . London: W.H. Lizars, ... S. Highley, ... London; and W. Curry, jun. and Co. Dublin.. Accessed April 27, 2012 at http://books.google.com/books?id=4xAAAAAAQAAJ&printsec=frontcover#v=onepage&q&f=false .

IUCN SSC Canid Specialist Group 2008, 2008. "IUCN Red List of Threatened Species" (On-line). Dusicyon australis. Accessed February 15, 2012 at http://www.iucnredlist.org/apps/redlist/details/6923/0 .

Lyras, G., A. Van der Geer. 2003. External brain anatomy in relation to the phylogeny of Caninae (Carnivora: Canidae). Zoological Journal of the Linnean Society , 138: 505-522. Accessed February 15, 2012 at http://users.uoa.gr/~geeraae/publications/2003-Linnean-Caninaebrain.pdf .

Osgood, W. 1934. The Genera and Subgenera of South American Canids. Journal of Mammalogy , 15/1: 45-50. Accessed February 15, 2012 at http://www.jstor.org/stable/1373896 .

Renshaw, G. 1905. More natural history essays . London: Sherratt & Hughes. Accessed April 27, 2012 at http://books.google.com/books?id=0OAHAQAAIAAJ&pg=PA77&lpg=PA77&dq=Renshaw+%25E2%2580%259CThe+Antarctic+Wolf%25E2%2580%259D&source=bl&ots=A0-i5IX5dg&sig=qo2uXQvFqzJuhxACfTRMl_ppa6w&hl=en&sa=X&ei=VYSDT7WrC7Cr0AHaw5DzBw&ved=0CC4Q6AEwAg%23v=onepage&q=Renshaw%2520%25E2%2580%259CThe%25#v=onepage&q=Renshaw%2520%25E2%2580%259CThe%25&f=false .

Slater, G., O. Thalmann, J. Leonard, R. Schweizer, K. Koepfli, J. Pollinger, N. Rawlence, J. Austin, A. Cooper, R. Wayne. 2009. Evolutionary history of the Falklands wolf. Current Biology , 19/20: R937-R938. Accessed February 15, 2012 at http://www.cell.com/current-biology/abstract/S0960-9822%2809%2901695-9 .

Slater, G., O. Thalmann, J. Leonard, R. Schweizer, K. Koepfli, J. Pollinger, N. Rawlence, J. Austin, A. Cooper, R. Wayne. 2009. Supplemental Data for Slater et al. Current Biology , 19/20: R937-R938. Accessed February 15, 2012 at http://www.cell.com/current-biology/supplemental/S0960-9822%2809%2901695-9 .

2012. "Falkland Island Wolf Photo" (On-line). ARKive. Accessed February 15, 2012 at http://www.arkive.org/falkland-island-wolf/dusicyon-australis/image-G42426.html .