Philippine warty pig

Philippine warty pig
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Artiodactyla
Family: Suidae
Genus: Sus
Species:
S. philippensis
Binomial name
Sus philippensis
Nehring, 1886

The Philippine warty pig (Sus philippensis) is one of four known species in the pig genus (Sus) endemic to the Philippines. They have tufts of hair on the top of their head and on the lower sides of their jaws, as well as four warts on their faces. Their skulls are elongated; males have tusks and bigger skulls than females, an example of sexual dimorphism. They are considered Vulnerable by the IUCN, and their population is currently declining due to multiple threats. The pigs are probably nocturnal.

The species was scientifically described in 1886 by Alfred Nehring. There are three recognized subspecies; two of which were described in the nineteenth century, and the third in 2008 based on skeletal remains.

Description[edit]

Philippine warty pigs usually have black or dark brown fur, as well as recognizable white tufts on the side of their lower jaw (the gonion). Male pigs have four facial "warts", tusks, and gonial tufts which are larger and yellower than those of the females.[2][3]: 2  In general, Suid pig males are larger substantially larger and tuskier than females.[4] They also have tufts of hair on the tops of their heads, called crown tufts, and small "manes" on the back of their necks (but not further down their backs). Their heads of elongated and downward-sloping.[5]: 181 

As with many members of the genus Sus, the pigs' straight lower canines are triangular in cross-section. The canines curve upwards and compromise the male pigs' tusks. In fact, the lower surface of Philippine warty pigs' canines is typically 150% greater in diameter than the posterior surface.[6][7]: 25 [8]: 21 

An individual in a zoo in Cebu. Note the crown tuft.

Taxonomy[edit]

Sus philippensis was first scientifically described in 1886 by the German zoologist Alfred Nehring.[9]

Subspecies[edit]

There are three recognized subspecies of the Philippine warty pig:

  • S. p. philippensis, from Luzon and nearby islands. This subspecies has a grey forward-pointing crown tuft and large warts. It was described in 1886 by Nehring.[5]: 183 
  • S. p. mindanensis, from Samar, Leyte, and other islands near Mindanao. It has small warts, and black and red-brown crown tufts. Male's skulls are usually larger than females. It was described in 1897 by Charles Immanuel Forsyth Major, a Swiss zoologist-physician.[5]: 183 
  • S. p. oliveri, from Mindoro, was described more recently in 2008 by Colin Groves, a biologist-anthropologist. The description was done based on a collection of three skulls and part of a skin. They have "straw-coloured" gonial tufts, and their black crown tufts are equally mixed with straw-coloured hairs.[5]: 186 

Distribution and habitat[edit]

The Philippine warty pig is one of four species of pigs endemic to the Philippines. The other three endemic species are the Visayan warty pig (S. cebifrons), Mindoro warty pig (S. oliveri) and the Palawan bearded pig (S. ahoenobarbus), also being rare members of the family Suidae.[10]

In general, the original distribution of S. philippensis covered the western islands of the Philippines, while the original distribution of S. cebifrons covered the central and eastern islands. Specifically, the range of Philippine warty pigs included Luzon, Biliran, Samar, Leyte, Mindoro, Mindanao, Jolo, Polillo, Catanduanes, and possibly other islands.[2][11] They are known to be locally extinct from Marinduque.[1]

Wild pigs have been reported in Bohol and Sibuyan, although it is unclear whether these populations are S. cebifrons or S. philippensis. In April 2022, a Philippine warty pig was documented by a Department of Environment and Natural Resources (DENR) team while climbing Mount Apo.[12]

Ecology and behaviour[edit]

However, its present distribution is declining and subject to severe fragmentation.[2] Moreover, it was formerly found in most habitats (from sea level to up to 2800 m) but is now confined to remote forests due to habitat disruption and fragmentation, heavy hunting, and attacks of African swine fever, a potentially fatal viral fever.[2][11][13]: 1605  Wild pig meat in the Philippines can fetch more than twice the price of domestic pig meat.[2]

Usage of camera traps has suggested that the pigs prefer open, as opposed to canopied, habitat areas. Further evidence also suggested they do well in more open areas, near clearings or farms, and even inhabit banana plantations.[14]: 1609 

A 2022 paper noted that the pigs act as "ecosystem engineers" in that they reshape and influence their ecosystems. The pigs are known to help disperse seeds and influence plant growth and soil erosion.[14]: 1606  They are mostly nocturnal animals in areas where humans have disrupted the land.[2]

Little is known about the pigs' reproduction; however, in general, Suidae have between one and twelve babies in a den, which the piglets leave after about ten days. They reach sexual maturity after around 18 months.[2][4] One generation of pigs generally spans seven years.[1]

Hybridization[edit]

Due to loss of its natural habitat from human disruption, the Philippine warty pigs come into close contact with domestic pigs – the domesticated variety of the foreign Eurasian wild boar. Genetic pollution of the Philippine warty pig populations is a major problem, as is hybridization between the two species.[2][1][15]

See also[edit]

References[edit]

  1. ^ a b c d Heaney, L.; Meijaard, E. (2017). "Sus philippensis". IUCN Red List of Threatened Species. 2017: e.T21176A44139795. doi:10.2305/IUCN.UK.2017-3.RLTS.T21176A44139795.en. Retrieved November 12, 2021.
  2. ^ a b c d e f g h "Philippine Warty Pig (Detailed Profile)". WPSG. Archived from the original on January 12, 2024. Retrieved January 12, 2024.
  3. ^ Villegas, Jhonnel P.; Ibañez, Jayson C.; Rosales, Jireh R. "Conservation and population status of the Philippine warty pig (Sus philippensis) within the Obu Manuvu Ancestral Domain in Davao City, Mindanao Island, Philippines". The Technical Journal of Philippine Ecosystems and Natural Resources. 32 (1): 1–14 – via ResearchGate.
  4. ^ a b Whyte Macdonald, David (1984). Whyte Macdonald, David (ed.). The Encyclopedia of Mammals. New York: Facts on File. pp. 500–503. ISBN 0-87196-871-1. Archived from the original on February 16, 2024.
  5. ^ a b c d Groves, Colin P. (2008). "Taxonomy of wild pigs (Sus) of the Philippines". Zoological Journal of the Linnean Society. 120 (2): 163–191. doi:10.1111/j.1096-3642.1997.tb01277.x. S2CID 201961105.
  6. ^ Wehr, Nathaniel H.; Hess, Steven C.; Litton, Creighton M. (2018). "Biology and Impacts of Pacific Islands Invasive Species. 14.Sus scrofa,the Feral Pig (Artiodactyla: Suidae)". Pacific Science. 72 (2): 177–198. doi:10.2984/72.2.1. ISSN 0030-8870. S2CID 89846152.
  7. ^ Lucchini, Vittorio; Meijaard, Erik; Diong, Cheong H.; Groves, Colin P.; Randi, Ettore (2005). "New phylogenetic perspectives among species of South-east Asian wild pig ( Sus sp.) based on mtDNA sequences and morphometric data". Journal of Zoology. 266 (1): 25–35. doi:10.1017/S0952836905006588. ISSN 0952-8369.
  8. ^ Albarella, Umberto (December 6, 2007). Pigs and Humans: 10,000 Years of Interaction. OUP Oxford. ISBN 978-0-19-920704-6.
  9. ^ "Sus philippensis Nehring, 1886 | COL". www.catalogueoflife.org. Retrieved February 16, 2024.
  10. ^ Layos, John King N; Geromo, Ronel B; Espina, Dinah M; Nishibori, Masahide (March 28, 2022). "Insights on the historical biogeography of Philippine domestic pigs and its relationship with continental domestic pigs and wild boars". PLOS ONE. 17 (3): e0254299. Bibcode:2022PLoSO..1754299L. doi:10.1371/journal.pone.0254299. ISSN 1932-6203. PMC 8959178. PMID 35344556.
  11. ^ a b "Sus philippensis of Philippine Mamillian Fauna". The Field Museum. September 23, 2006. Archived from the original on September 23, 2006. Retrieved January 13, 2024.
  12. ^ "Rare sighting of near-endangered warty pig at Mount Apo a sign nature is healing: DENR". Coconuts Manila. April 19, 2022. Archived from the original on June 30, 2022. Retrieved April 21, 2022.
  13. ^ Cabanas, Al John C.; de Guia, Anna Pauline O.; Vega, Renato S. A.; Dimalibot, Judeline C. (2022). "Occurrence and Distribution of Philippine Warty Pig (Sus philippensis Nehring, 1886) in Mt. Banahaw de Tayabas, Luzon Island, Philippines". Philippine Journal of Science. 151 (5): 1605–1621. doi:10.56899/151.05.06. ISSN 0031-7683.
  14. ^ a b C. Cabanas, Al John; De Guia, Anna Pauline O.; Vega, Renato S.A.; Dimalibot, Judeline C. (October 2022). "Occurrence and Distribution of Philippine Warty Pig (Sus philippensis Nehring, 1886) in Mt. Banahaw de Tayabas, Luzon Island, Philippines". Philippine Journal of Science. 151 (5): 1605–1621. doi:10.56899/151.05.06. ISSN 0031-7683.
  15. ^ "Visayan Warty Pig Conservation Programme". Philippines Biodiversity Conservation Foundation. 2014. Archived from the original on April 19, 2019. Retrieved August 18, 2018.

External links[edit]