Habitat and Ecology
In common with most of the other suids, babirusa are omnivorous and both wild and captive individuals consume a wide variety of leaf, root, fruit and animal matter (invertebrates and small vertebrates). They visit volcanic salt licks and drink the water and ingest the soil (Clayton, 1996; Leus et al., 2002). Although detailed studies of their diet in the wild still need to be carried out, a review of the available information from the wild combined with studies on the stomachs and digestive abilities of captive animals suggest that from an anatomical/digestive point of view, they are most likely non-ruminant forestomach fermenting frugivores/concentrate selectors (Leus et al., 2004). Their jaws and teeth are reported to be strong enough to crack very hard nuts with ease. However, babirusa do not exhibit the rooting behaviour typical of other suids because of the absence of a rostral bone in the nose. They will probe soft sand as well as wet, muddy places for food.
In northern Sulawesi groups or troops of up to 13 individuals have been observed in rainforest, especially around water, communal wallowing areas and salt licks (Patry et al., 1995; Clayton, 1996). Older adult males were often observed singly and most groups were composed of five or fewer animals, the majority of which were females with young animals.
IUCN Red List Assessment
Red List Category
Red List Criteria
The species is also increasingly threatened by commercial logging, and by the spread of other land-uses resulting in forest conversion and degradation (MacDonald 1993; Riley 2002). Total lowland forest loss on the island is estimated to be likely more than 75% (Riley 2002).
The species occurs in several protected areas of various levels on Sulawesi (e.g. Bogani Nani Wartabone National Park, Lore Lindu National Park, Rawa Aopa Watumohai National Park, the Nantu Wildlife Reserve, the Panua Nature Reserve, Morowali Nature Reserveand others (Macdonald, 1993; Alvard, 2000, Riley, 2002; Wiles et al., 2002, http://www.bbc.co.uk/nature/animals/features/274feature3.shtml - accessed 5 June 2008)) The species often remains under hunting pressure even in protected areas.
There is an international studbook for the world captive population of the Sulawesi babirusa and both the European Association of Zoos and Aquaria (EAZA) and the Association of Zoos and Aquariums (AZA) have cooperative breeding programmes for the species, cooperating with the South East Asian Zoos Association (SEAZA). The founders of this population likely originated from northern Sulawesi. Ongoing genetic studies will hopefully help to resolve this origin question.
North Sulawesi babirusa
The North Sulawesi babirusa, Babyrousa celebensis, is a pig-like animal native to northern Sulawesi and the nearby Lembeh Islands in Indonesia. It has two pairs of large tusks composed of enlarged canine teeth. The upper canines penetrate the top of the snout, curving back toward the forehead. The North Sulawesi Babirusa is threatened from hunting and deforestation.
The common and scientific names are various transcriptions of its local name, which literally translated means "pig-deer" (from Malay babi "pig" + rusa "deer" - see also Javan Rusa) in reference to the huge tusks of the male suggestive of a deer's antlers.
Together with the other members of the genus Babyrousa, the North Sulawesi Babirusa has usually been considered a subspecies of a widespread Babyrousa babyrussa, but recent work suggests that there may be several species, differentiable on the basis of geography, body size, amount of body hair, and the shape of the upper canine tooth of the male. Following the split, the "true" Babyrousa babyrussa is restricted to Buru and the Sula Islands.
Most experts agree that babirusas are part of the pig family, and are one of the oldest living members of the family, representing a subfamily, Babyrousinae, that branched off from the warthog branch of the pig family (Subfamily Phacochoerini) during the Oligocene or early Miocene.
The north Sulawesi babirusa has a head-and-body length of 85–110 cm (33–43 in) and weighs up to 100 kg (220 lb). It is virtually hairless (easily revealing its greyish skin), and the tail-tuft is also nearly hairless. In males, the relatively long and thick upper canines are strongly curved. They emerge through the roof of the snout, while the long lower canines emerge through the side of the mouth. The upper canines can grow backwards in a curve until they penetrate the skull of the male babirusa. 
In females, the canines are far shorter and typically do not protrude. In comparison, the Buru babirusa has relatively long, thick body hair, a well-developed tail-tuft, and relatively short and slender upper canines in males, while the Togian babirusa is larger, has a relatively well-developed tail-tuft, and the upper canines of the male are "short, slender, rotated forwards, and always converge".
Its habitat is the underbrush of tropical forests and canebrakes, and the shores of rivers and lakes. Its mostly-hairless, mottled-grey-and-brown hide provide it with a degree of camouflage. The North Sulawesi Babirusa is known for its two pairs of tusks; both its upper and its lower pairs of canine teeth are greatly enlarged, and curve up and back towards the head. The upper canines of the male are so curved and enlarged that they emerge through the flesh, by way of holes, to pass through the top of the snout.
This species is protected by Indonesian law but is threatened by illegal hunting.
Because it is split-hooved and has a three-chambered stomach (and was thus thought to be a ruminant for a long time), there was some dispute in Halakha (Jewish law) as to whether the babirusa is, in fact, kosher (permitted according to Jewish dietary laws). Eventually it was found that the animal is not a true ruminant, and thus remains trefe, like other pigs.
In captivity, the species is very inbred. The Bronx Zoo has an excellent breeding record for this animal. There are not many zoos that have bred the animal; some that have are St. Louis Zoo, Los Angeles Zoo, South Lakes Wild Animal Park, Marwell Wildlife, and Chester Zoo.
In 2006, a male North Sulawesi Babirusa and a female domestic pig were accidentally allowed to interbreed in the Copenhagen Zoo. The offspring were 5 hybrid piglets with teeth most resembling the North Sulawesi Babirusa, while their colour was highly variable.
- Leus, K. & Oliver, W. (2008). Babyrousa celebensis. In: IUCN 2008. IUCN Red List of Threatened Species. Retrieved 15 November 2008.
- Meijaard, E. and Groves, C. P. (2002). Upgrading three subspecies of Babirusa (Babyrousa sp.) to full species level. IUCN/SSC Pigs, Peccaries, and Hippos Specialist Group (PPHSG) Newsletter 2(2): 33-39.
- Meijaard, E., J. P. d'Huart, and W. L. R. Oliver (2011). Babirusa (Babyrousa). Pp. 274–276 in: Wilson, D. E., and R. A. Mittermeier, eds. (2011). Handbook of the Mammals of the World. Vol. 2, Hoofed Mammals. ISBN 978-84-96553-77-4
- Nash, D. (February 23, 2010). The many babirusa species (babirusas, part VI). Scienceblogs. Accessed May 1, 2012
- Clayton, L. M.. "Effects of a Proposed Ex situ Conservation Program on In situ Conservation of the Babirusa, an Endangered Suid" Conservation Biology 14. 2 (2000), 382-385.
- http://denmark.dk/portal/page?_pageid=374,610590&_dad=portal&_schema=PORTAL&ic_itemid=929035[dead link]