Crab-Eating Macaque: Characteristics, Behavior, and Habitat

Written and verified by the vet Eugenio Fernández Suárez

Last update: 21 December, 2022

The crab-eating Macaque (Macaca Fascicularis) is one of the most popular primate species for tourists visiting countries like Indonesia or Thailand. However, some of their behavior is unfamiliar to visitors to these exotic places.

Characteristics of the crab-eating macaque

The crab-eating macaque has had a close relationship with humans. To some people, they were a plague and invasive species. However, some cultures consider them to be sacred animals.

Unfortunately, the biomedical industry has also used them. In fact, they are one of the primates that has participated in most experiments. Recently, an experiment cloned the first primate, and it was this exact species.

This primate belongs to a group of macaques. All of them are Asian monkeys, like the crab-eating macaque, with the exception of the Gibraltar macaque. They are medium-sized monkeys that don’t weigh more than 22 pounds. They also have brown fur and an elongated tail. In fact, some people call them the long-tailed macaques. Their tails can be more than 1.5 feet – in fact, they’re longer than their actual bodies!

The behavior of the crab-eating macaque

Crab-eating macaques live in groups made up of two females with one or more males. However, the males leave the group at puberty while the females remain with the group.

One of their most curious behavior patterns is that they use hair and fiber as dental floss to clean their teeth. This behavior has a cultural transmission. Some populations of the crab-eating macaque use fibers from different trees while others use human hair.

While this monkey’s name comes from their taste for crabs, the truth is that they have a varied diet that includes numerous species of plants, fruits, and roots. Sometimes, the nuts, crabs, and clams they eat are difficult to open. As a result, they use tools like rocks to open them.

Another interesting behavior pattern is how these monkeys eat. They clean potatoes with water and even sometimes peel them before eating them.

Like other primates, these animals are very sociable creatures. They bond through grooming. They also have strong ties to their mothers and other members of their group.

In some studies, researchers have found that mothers give food to their young even though the mother may be starving. Although this may sound like reasonable behavior, this is not common in the animal kingdom.

While this monkey’s name comes from their taste for crabs, the truth is that these animals have a varied diet that includes numerous species of plants, fruits, and roots. Sometimes, the nuts, crabs, and clams they eat are difficult to open. As a result, they use tools like rocks to open them.

Habitat

The crab-eating macaque lives in various habitats in southeast Asia. They live mainly in tropical forests, but also in coastal mangroves that give them mollusks and crustaceans to eat as well.

This monkey’s habitat is in regions such as Bangladesh or Malaysia, as well as islands such as Sumatra, Java, or Borneo. In tourist areas, it’s important not to disturb these primates. If disturbed, they can become aggressive and dangerous. This behavior can also be aggravated by diseases.

Crab-eating macaques are not endangered. In fact, there are many healthy populations and they have even become an invasive species in some countries. Experts consider these monkeys as one of the 100 most harmful invasive species, primarily because they eat eggs of threatened birds.

One of their most curious behaviors is that these animals use hair and fiber as dental floss to clean their teeth. This behavior has a cultural transmission. Some populations of the crab-eating macaque use fibers from different trees while others use human hair.