Pygmy hog (Porcula salvania)

Synonyms: Sus salvanius
  
French: Sanglier Nain, Sanglier Pygmée
Spanish: Jabalí Enano, Jabalí Pigmeo
KingdomAnimalia
PhylumChordata
ClassMammalia
OrderCetartiodactyla
FamilySuidae
GenusPorcula (1)
SizeMale head-body length: 61 - 71 cm (2)
Female head-body length: 55 - 62 cm (2)
Male weight: 8 - 10 kg (2)
Female weight: 6 - 8 kg (2)

Classified as Critically Endangered (CR) on the IUCN Red List 2007 (1), and listed on Appendix I of CITES (3).

As its common name suggests, the pygmy hog is the smallest of all the pig family; it is also the most endangered. These small hogs have relatively short limbs, the back is short and rounded and the tail is extremely short (2). The coat is grey brown along the back and pale on the underparts, it is longest behind the shoulders (2). Newborns are greyish pink in colour, later developing a brown coat with faint ochre stripes before attaining adult colouring (4). Adult males are larger and more robust than females; they have visible tushes (canine teeth) and a band of dark hair along the ridge of the nose (2). Soft grunting calls are used to maintain contact between individuals within their dense habitat (2). Recently, genetic evidence has shown that the pygmy hog is the sole member of the genus Porcula, and is not a member of the genus Sus, which contains the domestic pig (5).

Thought to previously be found in a range south of the Himalayan foothills in Nepal, Bhutan and India (6), the pygmy hog was feared to be extinct by the 1960s but was 'rediscovered' in 1971. Since then however, numbers have fallen dramatically and the only viable population is today found within Manas National Park in north-western Assam, India (2).

Pygmy hogs occupy typical floodplain habitats, such as secondary successional forests, dense tall grasslands and mixed scrub associations (2).

Female pygmy hogs are found in small groups, known as 'sounders', composed of one or two adults and their young (4). Males are solitary except for during the mating season, which begins towards the end of November (2). Rival males compete for access to females during this time and will use threatening displays that are also typical of other members of this genus; adopting a broadside stance, their hair bristles and they turn their heads yawning and curling the lips to show their canine teeth (2). Pregnant females will move away from their group to give birth, usually to a litter of four to six piglets after a gestation period of around 120 days (2). Pygmy hogs are unusual in that both sexes use nests year round. The whole family makes use of the nest constructed in a depression on the ground and lined with grasses (4).

Pygmy hogs forage for a wide variety of foods, eating roots, grasses, fruits, insects and earthworms amongst others (2). Groups occupy small home ranges of about 25 hectares (7) and regularly used paths can be seen amongst the tall elephant grasses. Travelling single file, the adults of the group take up the front and the rear of the procession (4).

The tall grassland habitat of the pygmy hog has been extensively destroyed by development, agriculture, domestic grazing and deliberate fires (2). The only viable population of pygmy hogs is today restricted to Manas National Park, and it is thought that possibly as few as 100 to 150 pygmy hogs remain (4). Even within the park boundaries there are threats from livestock grazing, poaching and fire; whilst continued political unrest in the area severely hampers effective conservation efforts (2).

The pygmy hog is protected under Schedule I of the Wildlife (Protection) Act 1972 in India and international trade is banned by its listing on Appendix I of the Convention on International Trade in Endangered Species (CITES) (2). Manas National Park was declared a UNESCO World Heritage Site in 1986 (2). The Pygmy Hog Conservation Programme (PHCP) was established in 1995, under the aegis of a formal 'International Conservation Management and Reseach Agreement (ICMRA)' between the Pigs, Peccaries and Hippo Specialist Group (8) of the IUCN, the Durrell Wildlife Conservation Trust (9) and relevant local and national governmental authorities (2). The PHCP has carried out a multi-faceted strategy, including field status surveys, behavioural studies, captive breeding, personnel training and local community awareness and assistance programmes (2). The Pygmy Hog Research and Breeding Centre near Guwahati in Assam was established in 1996, and by the year 2000 the only captive population of this species had grown from the original six individuals to a total of 77 (2). In 2008, 16 of these pygmy hogs were released into the Sonai Rupai Wildlife Reserve, where they will be carefully monitored (10). The captive population is a potentially crucial insurance for keeping this small pig from extinction (2).

For more information on the pygmy hog see:

Authenticated (10/01/03) by William Oliver. Chair, Pig, Peccary and Hippos Specialist Group.
http://www.iucn.org/themes/ssc/sgs/pphsg/home.htm

  1. IUCN Red List (November, 2007)
    http://www.iucnredlist.org
  2. Narayan, G. and Oliver, W.L.R. (1/1/0001 12:00:00 AM) Pygmy Hog. In Mammals of South Asia,.
  3. CITES (December, 2002)
    http://www.cites.org
  4. Ultimate Ungulate (December, 2002)
    http://www.ultimateungulate.com/Artiodactyla/Sus_salvanius.html
  5. Funk, S.M., Verma, S.K., Larson, G., Prasad, K., Singh, L., Narayan, G. and Fa, J.E. (2007) The pygmy hog is a unique genus: 19th century taxonomists got it right first time round. Molecular Phylogenetics and Evolution, 45(2): 427 - 436.
  6. UNEP-WCMC Species Fact Sheet (November, 2007)
    http://www.unep-wcmc.org/species/data/species_sheets/pyghog.htm
  7. Macdonald, D. (2001) The New Encyclopedia of Mammals. Oxford University Press, Oxford.
  8. IUCN/SSC Pigs, Peccaries and Hippos Specialist Group (December, 2002)
    http://www.iucn.org/themes/ssc/sgs/pphsg/home.htm
  9. Durrell Wildlife Conservation Trust (December, 2002)
    http://www.durrell.org
  10. BBC News: Rare pygmy hogs head for the wild (May, 2008)
    http://news.bbc.co.uk/1/hi/world/south_asia/7408152.stm