Javan warty pig
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Suidae
Genus: Sus
Species:
S. verrucosus
Binomial name
Sus verrucosus
Boie, 1832
Range map of Javan warty pig

The Javan warty pig (Sus verrucosus), also called Javan wild pig, is an even-toed ungulate in the family Suidae. It is endemic to the Indonesian islands Java and Bawean, and is considered extinct on Madura. It is listed as Endangered on the IUCN Red List since 1996.[1]

Characteristics

The Javan warty pig is black, with some rufous parts on the head and the belly. It has three pairs of facial warts; the largest pair is below the ears, the second under each eye, and the smallest pair above the upper canines. It has a nuchal and dorsal crest that gradually becomes shorter towards the tail. Its tail does not have a terminal tuft. Young are uniformly coloured.[2] Facial warts vary in size and grow with age. Males reach a weight of about 108.2 kg (239 lb), whereas females weigh only about 44 kg (97 lb).[3]

Distribution and habitat

The Javan warty pig occurs in Leuweung Sancang Nature Reserve and Meru Betiri National Park in southern Java, Nusakambangan Nature Reserve on the Nusa Kambangan island and in a protected area on the Bawean island. It lives at elevations below 800 m (2,600 ft) in grassland and secondary forest.[3]

Ecology and behaviour

The Javan warty pig is mainly a solitary creature, but groups of three or four individuals have been sighted. It is nocturnal and crepuscular. When the warty pig is startled, its mane stands erect. If the animal is fleeing from a predator, its tail is erect and curved towards its body. When a group of individuals is frightened, the recorded alarm call sounds like a shrill whistle.[3]

Reproduction

September to December is thought to be the mating season of the Javan warty pig. Gestation lasts four months. The piglets are born in a nest and nursed for the following three to four months. On average, the species lives to be eight years of age, with a few captive individuals living to 14 years of age.[4]

The specific mating structure of the Javan warty pig has not been observed in the wild. A historic source from the 1940s indicated a litter size of three to nine piglets born between January and March.[3] Between 2003 and 2005, captive Javan warty pig in Surabaya Zoo had litters of two to four piglets, born between March and August.[5]

Conservation

According to the IUCN Red List, S. verrucosus was first declared vulnerable in 1988 and listed as endangered in 1996. A drastic 53% drop in the population occurred from 1982 through 2006. The species is believed to be still declining.[1] A recent study estimated a population of 172–377 individuals, making the Javan warty pig one of the rarest pig species.[6] The main threat to this species is habitat encroachment by humans. Agriculture is a large influence in the decline of the Javan warty pig. These pigs are also killed by farmers who spot the pigs raiding their crops at night. Since this is a large animal, sports hunters also consider killing the animal a challenge and see it as a trophy. An interesting threat to this species is actually occurring naturally. The closest relative to Sus verrucosus is the banded pig (Sus scrofa vittatus). This species shares similar habitat ranges as the Javan pig. This species threatens the Javan pig not only through resource competition, but also by cross-mating and creating hybrids of S. verrucosus and S. scrofa.[7]

The most recent conservation project, through the World Association of Zoos and Aquariums, aims to capture healthy Javan warty pigs and breed them in captivity. The offspring of this program are then supposed to be released into protected habitats.[7] This method of reintroduction of the offspring will ensure the long-term survival of the species. One of the problems with this project is finding true S. verrucosus, not hybrids, which brings up another goal of the program, molecular mapping. Scientists will extract DNA from the wild pigs and record their genetic code to separate hybrids from true S. verrucosus. Along with this project are plans to educate the locals about the importance and endangerment of this species. The locals sometimes comment that they cannot distinguish the banded pig from the Javan pig, and with education, this confusion can be reduced.[8]

References

  1. ^ a b c Semiadi, G.; Rademaker, M. & Meijaard, E. (2016). "Sus verrucosus". IUCN Red List of Threatened Species. 2016: e.T21174A44139369. doi:10.2305/IUCN.UK.2016-1.RLTS.T21174A44139369.en. Retrieved 16 November 2021.
  2. ^ Lydekker, R. (1915). ""Sus Verrucosus"". Catalogue of the Ungulate Mammals in the British Museum of Natural History, Volume IV. London: Trustees of the British Museum. pp. 336−338.
  3. ^ a b c d Blouch, R. (1993). "The Javan Warty Pig (Sus verrucosus)". In Oliver, W. L. R. (ed.). Pigs, Peccaries, and Hippos. Status Survey and Conservation Action Plan. Gland: IUCN/SSC Pigs and Peccaries Specialist Group, IUCN/SSC Hippo Specialist Group. pp. 129−136. ISBN 2-8317-0141-4.
  4. ^ Grzimek, B. (1972). Grzimek's Animal Life Encyclopedia. New York: Litton World Trade Corporation.
  5. ^ Semiadi, G.; Nugraha, R. T. P. (2009). "Some Notes on Biological Aspects of Captive Javan Warty Pig (Sus verrucosus)". Biodiversitas. 10 (3): 124−128. doi:10.13057/biodiv/d100304.
  6. ^ Rademaker, M.; Meijaard, E.; Semiadi, G.; Blokland, S.; Neilson, E.W.; Rode-Margono, E.J. (2016). "First ecological study of the Bawean Warty Pig (Sus blouchi), one of the rarest pigs on Earth". PLOS ONE. 11 (4): e0151732. Bibcode:2016PLoSO..1151732R. doi:10.1371/journal.pone.0151732. PMC 4822801. PMID 27049756.
  7. ^ a b "ZGAP – Projects – Conservation of the Javan Warty Pig in Indonesia". ZGAP – Zoologische Gesellschaft Für Arten- Und Populationsschutz E.V. The World Association of Zoos and Aquariums. 15 November 2011. Archived from the original on 2 October 2011.
  8. ^ "Cikananga Wildlife Center – Javan Warty Pig". Cikananga Wildlife Center. Archived from the original on 14 December 2014. Retrieved 9 December 2011.

External links

Extant Artiodactyla species
Taxon identifiers
Categories