Babirusa

Babirusas are known for their unique, curving tusks that are in fact teeth and give them a more prehistoric appearance than many modern animals. They are referred to as deer-pigs due to their resemblance to large pigs and tusks like a deer‘s antlers. These omnivores eat plants, fruits, berries, insects, and carrion. The babirusa is found on the Sulawesi, Sula, Buru, and Togian islands in Indonesia.

4 Incredible Babirusa Facts!

• The tusks on the upper snout of this animal are actually canine teeth that have grown up and broken through the skin.
• These mammals communicate with one another by grunting, growling, and chattering their teeth.
• Scientists are not certain about the true purpose of a male babirusa’s tusks.
• Cave paintings of babirusas thought to be 35,400 years old were found on the island of Sulawesi.

Scientific Name

The babirusa belongs to the genus Babyrousa. Previously, all the members of the genus were thought to be the one species, Babyrousa babyrussa, but when morphological and genetic differences were discovered in 2002, the genus split into separate species.

They belong to the Suidae family. The Malaysian word “babirusa” translates to deer-pig.

Types of Babirusa

There are three widely recognized species of babirusas that differ in the size of their bodies, teeth, and skull, as well as the amount of hair on their body and tail tuft. They are:

• North Sulawesi babirusa (Babyrousa celebensis): Also known as the Sulawesi babirusa due to their presence in the Sulawesi island and its neighboring islands Buton, Muna, and Lembeh, this species is probably the best-known of the babirusas. It has gray skin, and unlike the Buru babirusa it does not have hair on its body or tail tuft. Measuring around 85-110 cm (2.7-3.6 ft) in length and about 100 kg (220 lbs) in weight, it is smaller than the Togian babirusa. There is a sizable population in captivity.
• Buru babirusa (Babyrousa babyrussa): Called the hairy or golden babirusa, this species has golden-brown fur that is long and thick and a notable tail tuft. Its habitats are in the Indonesian islands of Buru, Taliabu, and Mangole.
• Togian babirusa (Babyrousa togeanensis): Located only on the Togian Islands, this species has shorter and thinner upper teeth than the North Sulawesi Babirusa. Their tusks always converge and they have a larger tail tuft.

There is another possible species under consideration: the Bola batu babirusa (Babyrousa bolabatuensis). This proposed species is found in Sulawesi and is currently classed as a North Sulawesi babirusa. The IUCN does not recognize it and more research is needed to determine whether it should be a distinct species.

Evolution and Origins

The babirusa’s evolutionary history has been a subject of fascination for years for scientists since 1854, when explorer and naturalist Alfred Russel Wallace first began documenting the area in southeast Asia that was named after him and described this pig-like animal.

While much is still unknown about the babirusa’s history, based on fossil evidence there were thought to be two extinct subspecies prior to the 2002 taxonomic division. One extinct subspecies from southwestern Sulawesi, B. babyrussa beruensis, was traced back to the Pleistocene epoch of 2.58 million years ago to 11,700 years ago and was larger than the modern babirusa. The other extinct subspecies, B. babyrussa bolabatuensis, from the south-eastern region of Sulawesi was present in the Holocene period, 11,700 years to the present.

Other early evidence of babirusas are prehistoric paintings of the animals discovered in Sulawesi caves that are believed to have been created at least 35,400 years ago, sometime in the Pleistocene.

Appearance and Behavior

Babirusas have brown or grayish-colored skin with little body hair. Due to the length and rounded shape of their bodies, they have been likened to torpedos. Their legs are thin like those of a deer.

These animals can grow to reach 2-3 feet, 3-3.5 feet long, and weigh around 132-220 pounds, with the North Sulawesi babirusa the heaviest. A babirusa that is 3 feet tall would be about as high as 2.5 bowling pins stacked. One that is 220 pounds would weigh around the same as an adult panda bear.

The most well-known feature of this mammal is its tusks. It has two tusks on the lower half of its snout and two on the upper half. Though they are called tusks, they are actually canine teeth. On its upper snout, the babirusa’s canine teeth grow, break through the skin, and curve upward and back toward the babirusa’s eyes. In fact, these curving teeth can grow so long, there is evidence that they can actually penetrate the skull of this animal and cause death.

Their lower canine teeth grow sideways and upward out of the babirusa’s mouth. Only male Sulawesi babirusas have full-sized tusks on the upper half of their snout. Females may have very small, short upper tusks or none at all. However, both males and females have tusks on the lower half of their snouts.

Babirusas have four-pointed, strong hooves that they use to dig. They dig up insects, insect larvae, plants, and roots. Also, when two males are fighting in competition for a female, the males use their hooves to strike each other. They rear up on their back feet, smashing into each other, kicking their hooves. It is a fierce and noisy competition!

Humans and feral, or wild, dogs are the only predators of adults. These mammals can run at speeds of up to 30mph. So, when they encounter a human or a feral dog, these shy mammals run and hide in a swampy area or rainforest. Their dark skin allows them to blend in with their muddy, swamp habitat.

Most males are solitary. Alternatively, females are social creatures living in groups of 80 or more babirusas. This large group includes only females and young babirusas.

Habitat

Babirusas live on islands in Indonesia including Togian, Sula, Buru, and Sulawesi. Wild babirusas don’t live anywhere else in the world except on these islands. These mammals live in a moist, tropical climate in swamps and in rainforests, near rivers. They take shelter in the underbrush and in canebrakes.

These swine roll around in the mud in order to cool themselves in this humid climate. This is also an effective way to get rid of any parasites on their skin. Another interesting behavior of these animals is called plowing. A male babirusa lowers itself to its knees and pushes its nose through the sandy ground. The babirusa has its mouth open and takes in the sand while releasing foaming saliva. This is strange behavior that scientists haven’t fully figured out. But they think plowing may be a way for a babirusa to mark its territory with its scent.

In addition, these animals are great swimmers so they tend to live near rivers. They’ve been known to swim a long distance from one island to another.

Diet

These animals are omnivores. Oftentimes, they use their hooves to dig in the ground in search of insects or larvae. They can stand on their back hooves supporting their body in order to eat leaves off the lower branches of a tree.

These animals eat a diet of plants, leaves, fruit, berries, insects, tree bark, and sometimes carrion. They eat fruit and berries off the ground. They dig for insects and pull bark off trees. If they find a dead animal (carrion) on the ground, they may eat it. It all depends on what food source is most plentiful in their swampy habitat at the time.

Predators and Threats

The animal’s only predators are humans and sometimes feral dogs. Some Indonesians hunt for babirusas in order to eat them.

The future of this mammal is at risk due to habitat loss as a result of logging activity. Poaching is another threat to these animals despite the existence of laws protecting them. Some locals even capture young babirusas and tame them to keep them as pets!

Reproduction, Babies, and Lifespan

The mating season of the babirusa is from January to August. Males fight one another in competition for females. It would seem logical that the males would use their upper and lower tusks as weapons when fighting for a female. But, in reality, their tusks are easily cracked and broken. Some scientists believe that the curved tusks on the upper part of the snout serve to protect the animal’s eyes during this competition for females. In fact, they will purposely move their heads to the side while they are fighting so their tusks won’t smack together. So, males use their pointed hooves and the overall strength of their bodies to fight in order to determine the strongest male. The most powerful male mates with several females.

The gestation period is 155 to 158 days. A wild boar, another member of the Suidae family, has a shorter gestation period of 115 days. Females give live birth to one to two babies in a litter. Each newborn baby, aka a piglet, weighs from 10 to 15 pounds. Some babies as young as three to ten days old start to eat solid foods. However, they will likely continue to nurse until they are completely weaned at six to eight months of age. Once they are weaned, they become independent.

A babirusa’s tusks continue to grow throughout its life. This is similar to the way a person’s fingernails grow throughout life. Sometimes the tusks on a male babirusa’s upper snout continue to grow and curve until one or both break through the top of the animal’s skull! This can eventually lead to death depending on how deeply the tusk goes into the animal’s skull.

Though these animals can live up to 10 years in the wild, they have been known to live up to 24 years in captivity.

Population and Conservation

According to the IUCN Redlist, the population of the Sulawesi babirusa is 9,999 mature individuals. Their population is decreasing, and they are listed with a conservation status of Vulnerable.

The population of the Togian Islands babirusa includes 1,000 mature individuals. They have a decreasing population as well and are listed as Endangered.

The population of the hairy babirusa (scientific name Babyrousa babyrussa) is unknown. This species of babirusa is listed as Vulnerable with a decreasing population.

1. Wikipedia, Available here: https://en.wikipedia.org/wiki/Babirusa
2. Saint Louis Zoo, Available here: https://www.stlzoo.org/animals/abouttheanimals/mammals/hoofedmammals/babirusa
3. Cool Green Science, Available here: https://blog.nature.org/science/2014/02/11/babirusa-conserving-the-bizarre-pig-of-the-sulawesi-forest/
4. Houston Zoo, Available here: https://www.houstonzoo.org/blog/national-pig-day1/