An Interesting Primate

White-faced saki monkeys live in the northeastern region of South America. The male is a handsome animal. He has a primarily white face, which forms a striking contrast with the black hair on the rest of his body. The female has greyish hair that is often decorated with reddish-brown areas. The animals are kept in captivity, which is not a good situation, especially for primates. The monkeys are an educational sight for visitors, though.

Some caretakers try to make the lives of the captive animals as interesting as possible. Finnish scientists have recently found that a tunnel that emits various sounds appears to be interesting for the animals. The researchers were surprised by the sound that seemed to be the animals’ favourite. The research has scientific value as well as being enjoyable for the monkeys.

Physical Features

The white-faced saki monkey’s scientific name is Pithecia pithecia. It’s also known as the pale-headed saki. The difference in appearance between the male and the female is referred to as sexual dimorphism. The male’s white face may have faint yellow or pale orange areas, but this doesn’t spoil its distinctiveness. The female has less rich colours, and there is less hair on her face. There is a light stripe extending from the inner corner of each of her eyes to the outer corner of her mouth.

Both genders have a nose that is noticeably flat and has bristly hairs underneath. Their fingers and toes are long and narrow. Unlike the tail of some monkeys, the saki monkey’s tail is not prehensile, so it can’t curl around objects and hold them. The tail is often as long as the body.

Diet and Behaviour

The monkey lives in the rainforest and spends almost all of its time in the trees. The animals are diurnal, which means that they are active during the day. They are very agile and are able to walk and leap through the tree canopy with ease. They walk quadrupedally along the branches. They are generally found in the middle or low canopy instead of the upper area. The primates are sometimes known as “flying monkeys” because of their impressive leaps between branches. The leaps may be as long as thirty-three feet.

The animals live in small groups and maintain a territory. Vocalizations within the group help to maintain social cohesion and may include duets. Different groups may threaten each other when they meet by producing sounds, shaking branches, and chasing the members of the other group. This is apparently done without serious harm appearing in either group.

The monkeys are omnivorous animals but eat mostly fruit. They also eat leaves, flowers, insects, and other small animals. They are important distributors of seeds in the forest. The primates sometimes become prey themselves. Snakes, birds such as the harpy eagle, and mammals such as jaguars may attack them. The harpy eagle (Harpia harpyja) is one of the largest eagles in the world. It’s black and white in colour and lives in both South and Central America. The monkeys retreat and hide from potential predators that they discover or intimidate or attack them as a group.

Reproduction and Lifespan

It’s unknown whether there’s a particular breeding season for the monkey in the wild. Gestation lasts for five months. Only one baby is born. The species appears to be monogamous, although some biologists question whether this is the case for the wild animals. There’s still a lot to learn about the wild primates as opposed to the captive ones.

Lifespan in the wild is said to be around fifteen years. In captivity, the monkeys have lived up to thirty-five years. Lifespan is quite often longer for an animal in captivity than in the wild if it’s given suitable food and treated by a veterinarian when necessary. It’s important that the animal is reasonably content during its longer lifetime.

Sound Enrichment for Captive Animals

The research exploring how white-faced saki monkeys respond to sound was performed by scientists from Aalto University in Finland in cooperation with a Finnish zoo. The scientists built prototypes of their sound-emitting device to discover which one the monkeys preferred. The tunnel-shaped one seemed to be their favourite version. It had a wooden floor and a transparent acrylic covering.

The device was interactive. The monkeys were able to trigger the production of sounds or sit in the tunnel without sounds if they preferred. The device recorded their choices so that the researchers could analyze the results. The sounds included rain, traffic, electronic music, and calm music that the researchers refer to as Zen. Interestingly, the animals listened to the traffic sound more than the other ones. As the researchers say, it’s important to avoid preconceived ideas in animal research.

The monkeys used the tunnel throughout the study, which lasted for several months. Sometimes they listened to music in the tunnel, but at others times they groomed each other or even slept there. The tunnel seems to have become a valued part of their lives.

Important Research

I think the research related to sound appreciation is important for more than one reason. If we keep intelligent animals such as primates in captivity, we owe them an interesting life. A large enclosure with at least a semi-natural habitat is important. The addition of enrichment activities, such as listening to different sounds, could be another way to provide interest in their life. Hopefully, devices with more sounds and perhaps with new ones added on a regular basis will be created, depending on how the monkeys react. The research could tell us more about white-faced sakis and make the lives of captive animals better at the same time.

References

• Information about white-faced saki monkeys from the New England Primate Conservatory
• Pithecia pithecia facts from the Smithsonian’s National Zoo and Conservation Biology Institute
• Sound enrichment in the animals from the phys.org news service (which includes a link to the research paper)