Binturong

Classification and Evolution

The Binturong (Arctictis Binturong) is a medium sized carnivore that is found inhabiting the dense forests of South-East Asia. It belongs to the same family as other small carnivores including Civets, Genets, Mongooses, and Fossa and shares a number of characteristics with them including a long snout and having more teeth than most other carnivorous mammals. The Binturong is thought to be most closely related to the Palm Civet and is the largest member of this family.

Also known as the Bearcat, the Asian Bearcat and the Asian Civet, the Binturong is an animal that was once commonly found throughout much of its historical range, but sadly, today they are a rare find in the thick jungles and very little is actually known about their behaviour in the wild. There are possibly nine different subspecies of Binturong which vary little in appearance but tend to be most easily distinguished by their size and geographic location.

Anatomy and Appearance

The Binturong is a large, heavy animal that can grow to more than a meter long from its snout to the tip of its tail, with females being up to 20% bigger and heavier than their male counterparts. They have very long, coarse and shaggy fur which varies from dark brown to black in colour and is tipped with grey, along with tufts of long and dark straight hair which protrude beyond the tops of their ears.

The Binturong (along with the Kinkajou of South America) is also unique among carnivorous mammals as they possess a prehensile tip to their tails, which acts almost like another leg helping both with climbing, and gripping onto branches to give the Binturong more stability.

The Binturong also has long, white whiskers that are thick and sensitive and are found both on their checks and above their brown eyes. These whiskers make it look like a cat, but its body is like that of a bear, which is why its nickname is “bearcat.”

Distribution and Habitat

The Binturong is an animal that was once natively found throughout China, India, Thailand, Cambodia, Laos, Malaysia, Indonesia, the Philippines and on the island of Borneo, and although there are populations still found in a number of these countries, their numbers have been declining and the Binturong can now be extraordinarily hard to spot.

Found in dense, moist jungles and in areas that are close to a slow-moving water source, the Binturong has been most affected by habitat loss particularly in the more southern parts of its natural range. Towards the north however where the rate of deforestation is not quite as ferocious, they have been more affected by hunting and capture as well as generally expanding human populations. The Binturong relies heavily on dense, thick forest where there is plenty of cover both in the trees and on the ground and with a big decline in its native jungles, this mammal simply has fewer places to go.

Behaviour and Lifestyle

The Binturong is a generally solitary and nocturnal animal that spends the majority of its time moving about slowly and cautiously amongst the trees. Due to their large size the Binturong cannot leap between one tree and another and so must climb down to the ground to go from tree to tree. They are excellent climbers and are well aided by their strong feet, agile bodies, semi-retractable claws and their prehensile tail. The Binturong is also known to both swim and dive well and often spends time in the water to simply cool down in the heat of the sun.

Although they do tend to be mainly solitary, small groups of Binturong are not uncommon and usually consist of an adult pair and their young. As with the hierarchy in Mongoose society, however, it is the female Binturong who remains the dominant adult. The Binturong is known to be a very vocal animal and makes a number of sounds to both communicate with other Binturongs and to warn off species that it sees to be a threat. They are known to make chuckling sounds when they seem to be happy and appear to utter a high-pitched wail if they become aggravated.

Binturong Reproduction and Life Cycles

Although there is not thought to be a mating season as such, there are thought to be higher instances between February and April and then later in July and November. After a gestation period that lasts for around three months, the female Binturong climbs down to the ground to nest in thick vegetation that is sheltered both from the elements but is also out of sight of passing predators.

Between one and three small cubs are born that measure about the size of a human fist. Like a number of other mammalian young, Binturongs are born blind and cannot hear and rely solely on their mother to provide them with milk. They are usually weaned by the time they are 2 months old and reach their adult size after a year. The Binturong is thought to live for between 10 and 15 years in the wild but can happily reach older ages in captivity with one individual having died at the age of 26.

Diet and Prey

Despite belonging to the carnivorous mammal group, the Binturong is mainly frugivorous meaning that it survives primarily on a diet that is comprised of fruit. Although they are also known to hunt insects, birds and rodents which they stalk in a cat-like manner amongst the branches, the Binturong has evolved well to eating in the trees with front feet that are not only designed to climb and dig, but they can also hold onto fruit and even open it with their agile toes.

The Binturong primarily hunts for food under the cover of night but is also known to feed while resting in the trees in the heat of the day. Due to their ability to swim and dive well, the Binturong also hunts fish in the water when cooling down in the heat of the day.

Predators and Threats

The Binturong is a relatively large and slow-moving animal, yet it is not really a main source of prey to the predators that also inhabit the dense, surrounding jungle. Larger animals such as Tigers and Snakes would pose the biggest threat to the Binturong adults, along with birds of prey and small carnivores that could easily target one of the young cubs. The biggest threat to the world’s Binturong population, though, is people and in a number of ways. The Binturong has been caught for their meat, captured and sold into the pet trade, subjected to vast habitat loss (mainly in the form of deforestation), and is also trapped and caught to be sold into the Chinese medicine market, where a number of their body parts are used in traditional remedies.

Interesting Facts and Features

Like other members of the Civet family, the Binturong has scent glands which are located just under its tail. These glands are used to mark trees and foliage to outline an individual’s territory and is distributed whilst the Binturong is moving about. Oddly enough, the odour of this scent is said to smell like buttered popcorn as do Binturong cubs when they are newborn. Until they became stronger and are more aware of their surroundings, young Binturong are incredibly vulnerable and are able to spray foul smelling liquid (like a Skunk) when they are really frightened. This is not a behaviour however that has been observed in individuals who are more than a couple of months old because as they get bigger they are able to defend themselves more easily.

When climbing, the Binturong is actually able to rotate its hind legs backwards so that their claws still have a good grip when climbing down a tree head first.

Relationship with Humans

This tree-dwelling mammal is actually known to be startlingly passive towards people and has been easily domesticated and kept as an exotic pet all over the world. However, it is this industry that along with other factors, has aided in the rapid decline of Binturong population numbers throughout Southeast Asia. Not only having been over-exploited as pets, zoo attractions, in medicines and for food, the Binturong is also subjected to devastating loss of vast areas of its natural habitat which has pushed the remaining populations into smaller and smaller pockets of their once large historical range. Both growing human settlements and forest clearance for agriculture are the main culprits, and since the Binturong needs dense jungle to successfully survive, plantations provide no sanctuary in their dwindling homelands.

Conservation Status and Life Today

Today, the Binturong is rarely seen in the wild with just a handful of sightings having been reported over the past decade. The Binturong is listed by the IUCN as a species that is Vulnerable from extinction in its natural environment in the near future. Human encroachment on their historical habitats has meant that their numbers have declined drastically and, along with their capture in many places, has led to a 30% decline in Binturong population numbers in the last 30 years.

Types

The Binturong is in the family Viverridae. There are supposedly nine subspecies of Binturong, but our research found only seven. They are separated into two clades (a group of organisms believed to have evolved from a common ancestor): the northern clade in mainland Asia is separated from the Sundaic clade (i.e., from the Sunda Islands in the Malay archipelago) by the Isthmus of Kra. Each subspecies is practically identical in appearance, but their genomes may contain key differences between individuals from different populations.

• Palowan binturong (Arctictis binturong whiteii) or bearcat is endemic to the island of Palawan in the Phillipines.
• The Cambodian Binturong (Arctictis binturong albifrons) may be the largest and most robust binturong. It has shaggier, longer, and darker fur with a more distinct margin between the pale silver-flecked face and the body fur.
• Malayan Binturong (Arctictis binturong binturong) lives on the Malay Peninsula.
• Bornean Binturong (Arctictis binturong pageli), endemic to northern Borneo and darker than other subspecies.
• Javan Binturong (Arctictis binturong penicillatus) lives on Java and possibly south Borneo.
• East-Sumatran Binturong (Arctictis binturong kerkhoveni) lives in East Sumatra.
• Chinese Binturong (Arctictis binturong menglaensis) relies on running to move around.