Proboscis Monkey

Nasalis larvatus larvatus

Easy (Polygynous)

The **Proboscis Monkey** (*Nasalis larvatus larvatus*) is a mid-sized primate featured in the *Planet Zoo* Southeast Asia Animal Pack.

## Zoopedia Description

### General

**Population In The Wild:** 7,000

The proboscis monkey is a species of primate that lives in the rainforests, mangroves and swamp forests of the Isle of Borneo (Indonesia, Malaysia and Brunei). The monkeys have dark orange fur on their backs and the top of their heads, paler orange fur on their backs and the top of their heads, paler orange fur on their chests, stomachs and upper arms and grey fur on their lower bodies, legs and forearms. Males have a distinctive elongated nose that hangs down over their lip. Females do not have this pronounced feature, although their noses are still quite prominent for primates. Males and females differ in size, with males being an average height of 66-76cm (26.4in-30.4in) and weighing between 16 and 22.5kg (35.2lb and 49.5lb), and females measuring between 53-62cm (21.2in-24.8in) in height and weighing between 7 and 12kg (15.4lb and 26.4lb).

The proboscis monkey is endangered, mainly due to the amount of deforestation that occurs to create oil palm plantations on the Island of Borneo. They are also hunted as a local delicacy in some areas and their body parts are sought after for traditional medicine. Proboscis monkeys are protected throughout Borneo; it is illegal to hunt or capture them. Their habitat is protected in some areas, but deforestation is still occurring at a rapid rate, often illegally.

### Social

Proboscis monkeys are social animals and live in 'bands' in the wild. This 'band' is often divided into smaller sub-groups made up of related females and their offspring and one alpha male. Males live together in groups until they become mature enough to become the alpha male of a group of females.

### Reproduction

The alpha male is usually the only one who mates with the females in his group, although subordinate males from bachelor groups may attempt to court females. During courtship, the male may vocalize at the female and the female may present her hind quarters to the male. Both may initiate courtship by pouting at each other. Copulation lasts around 30 seconds.

After a gestation of 166 to 200 days, the female will give birth to a single offspring. Female proboscis monkeys are extremely protective of their newborn and are unlikely to let any other monkey in the group help care for the infant. The female will carry the newborn on her body for the first few weeks of its life until it can walk on its own. Weaning occurs between 6 weeks and 7 months old. At around 1 year old the juvenile will begin distancing itself from its mother and gain more independence. Females reach sexual maturity at around 4 years old and are likely to remain with their natal group, although some do leave to join other groups. Male proboscis monkeys will leave their natal group at around 5 years old and join a group of other young males. They will reach full maturity at around 7 years old. At this time, they may acquire their own harem of females by ousting an older mature male or gathering a group of females without an alpha male. Alpha males will only remain with a group of females for 6 to 8 years before leaving or being ousted by a rival male. This is to prevent inbreeding.

## Animal Care

 FEEDING STATIONS
 FOOD ENRICHMENT
Small Barrel Feeder · Tree Forager · Fruit Spike Tree · Block of Frozen Fruit
Climbing Frame · Small ball · Small Ice Ball · Small Ball Colourful · Rubber Duck · Cardboard Box · Gift Box · Sprinkler · Block of Ice · Herb Scent Marker · Bobbin · Bobbin Drum · Mirror Mobile

## Trivia

### Zoopedia Fun Facts

* Proboscis monkeys have webbed toes and are good swimmers.
* The proboscis monkey is a very vocal species, with group members often calling to each other to bond, relay information or initiate mating.
* Alpha male proboscis monkeys make alarm calls to warn their group members of nearby danger.
* The large nose of the male proboscis monkey allows it to make bigger vocalizations, which in turn increases the likelihood of attracting females.
* The proboscis monkey has a ‘pot belly’ due to their stomach acting like that of a ruminant and breaking down tough-to-digest plant matter.

### Other Trivia

* The **Proboscis Monkey** was the first old world monkey added post-launch.
* It is also the first primate with the aquatic biome.