WEST AFRICAN POTTO

Perodicticus potto

Geographic Distribution and Habitat
Pottos inhabit a wide geographic range, spanning from the west African coast to Central Africa. These primates are prosimians–the oldest, most “primitive” group of primates—and are the only species in the genus Perodicticus. New potto species have been described within the last 50 years with much debate about which should be considered unique species and which should be considered subspecies. A careful consensus places pottos into three distinct geographic species:

  • The nominate West African potto, Perodicticus potto, lives throughout western Africa in Benin, Côte d’Ivoire, Ghana, Guinea, Liberia, Nigeria, Senegal, Sierra Leone, Togo, and possibly in Gambia and Guinea-Bissau.
  • The East African potto, P. ibeanus, crosses into eastern African territory and extends farther east than any other potto subspecies. This subspecies is found to the east and south of the Ubangi River, to the north of the Congo River, in the Democratic Republic of the Congo, to the east of the Lualaba River, to northwest Burundi, Rwanda, and Uganda, to the Kakamega and Nandi forests, and, lastly, extending into southwest Kenya.
  • The Milne-Edwards’s potto, P. edwardsi, occurs from the Niger River in Nigeria east through Cameroon, Equatorial Guinea (mainland), Republic of Congo, then south of the Congo River through the Democratic Republic of Congo (DRC) as far east as Irneti and as far south as Angola.

Pottos, in general, are extremely diverse and live in a plethora of habitats, from the coastal lowland forests of western Africa to the mid-to-high-altitude montane forests of Central Africa. They inhabit both primary and secondary forests, in areas of thick tropical rainforest vegetation; some are also found in swamp forest and other lowland forest along the coast.

Pottos are adaptable to different elevations and can survive from sea level to over 4,921 ft (1,500 m). In a few instances, pottos have even been spotted along vegetation on Mt. Kenya! They are typically found in trees that are 16-98 ft (5-30 m) tall.

West African potto range, IUCN 2020

Size, Weight, and Lifespan
An adult potto’s weight ranges from about 1.3 to 3.52 lbs (600-1,600 g). There is no noticeable size difference between males and females. Their lifespan in the wild has not been widely documented, but captive studies suggest that they can live up to 22-25 years.

Pottos vary regionally in size and body mass. Smaller pottos live in warmer, lower-elevation habitats and larger pottos live in cooler, higher-elevation forests. This is true of most species, with larger animals inhabiting cooler environments and smaller animals occupying warmer climates.

Appearance
Pottos have long, slender bodies which measure in size from 12-15 in (30-39 cm). The tail measures from about 1.5-4 in (3.7-10 cm). Their long and extendable limbs—which are key to their ability to cling to branches and trees—are nearly the same length as their body. Their dense coat varies in color from light to dark brown, and covers the entire body and forelimbs. The face is long and pointed and is most recognizable by large, dark eyes and hairless ears, which stick out to the sides. The bridge between the eyes and along the nose—called a scapular shield—is also hairless, and is an important feature when it comes to self defense. Covered by thick skin and tough bristles of sensory hair, the scapular shield is used to head-butt predators in battle.

Prosimians are the oldest species of primate, and have undergone thousands, even millions, of years of evolutionary and adaptational change. All prosimians have a grooming claw, sometimes called the toilet claw, which helps with arboreal grip and gives additional support when grasping trees with all four limbs. The location of this claw varies, but on the potto it is found on the second digit of their hind feet. Despite having vestigial index fingers, they have adapted to a have strong grip, due to highly flexible wrist and ankle joints. All in all, this small primate has one powerful grip!

What Does It Mean?

Gestation Period:
The time of pregnancy from conception until birth. 

Montane forest:
A forest that grows on the slope of a mountain, regardless of altitude or latitude, within a specific climate, just below the subalpine zone.

Subspecies:
A population usually restricted to a geographical area that differs from other populations of the same species, but not to the extent of being classified as a separate species.

Visit the Glossary for more definitions

Diet
The potto is mostly frugivorous. Their diet includes seasonal fruits, certain types of vegetation, and small arthropods. They prey upon slower insects that other animals of the forest find unpleasant—such as slugs, snails, ants, beetles, poisonous millipedes, and insect larva—and occasionally kill small vertebrate prey, such as bats or birds. Because certain fruits are only available in certain seasons, their diet and foraging behavior depend on the season. When fruits are sparse or out of season, they eat plant gums. Their relatively strong jaw enables them to eat the tough plant gums that few other animals of the forest can consume. They hunt insects by scent and quickly grab them with their hands and mouths. Their smaller index fingers help them grasp and consume their prey.

Pottos have a large stomach that expands and allow them to consume large amounts of food at one time. They can eat up to eight times their body weight! Consuming large quantities at once means that they do not have to spend as much time foraging, which can dangerous expose them to predators in sparsely protected fruit trees. After having their fill, they can quickly retreat to safety and take time to rest and digest.

Behavior and Lifestyle
Pottos are nocturnal, spending their days resting and nursing young, and are most active at night, searching their home ranges for food and potential mates. Some food sources, such as bats, and slower prey, like slugs, are easier to hunt at night when the potto is camouflaged by darkness.

Since most of the pottos’ natural predators sleep at night, this is a safer time for these slow-moving primates to venture out to forage. Pottos are masters of crypsis, the ability to avoid detection by predators. Their slow calculated movements are uniquely adapted to allow the potto to avoid predators that use sight and hearing to detect prey. The potto moves extremely slowly through the canopy with hardly a sound or vibration from movement. When pottos detect predators, they do not raise alarm calls, but rather remain completely still.

Fun Facts

Pottos have a special arrangement of blood vessels in their hands that allow for a super-strength grip.

Prosimian literally means “earlier than monkeys.”

The potto is also called the Bosman’s potto, referring to a 16th century Dutch merchant who allegedly described the species. 

Daily Life and Group Dynamics 
Pottos are relatively solitary primates, aside from when they are with their young or with a mate. Social behaviors, such as grooming, have been observed during courtship. Because of their slow, secretive moments, they rarely engage in play.

At night, mothers leave their young in a camouflaged and secure spot in the canopy and return to them at various points throughout the night. This is referred to as “parking” them. Female pottos require a home range large enough to provide food for their offspring; she will typically travel and forage an area of about 14-22 acres (6-9 ha). Males have substantially larger home ranges in order to cross paths with future mates. Depending on the area, their range can vary from as little as 22 to as much as 98 acres (9-40 ha).

Communication
Pottos lack strong verbal communication. As stated above, they remain under the radar and act very cautiously to avoid predators. Verbal communications and vocalizations might give away their location to predators who hunt by sound. Since pottos are not very social animals, they have less need to communicate with each other. After all, they spend much of their active time alone.

Though used infrequently, they have several calls that they use to determine location, to fight off predators when confronted, and during copulation. Most commonly, they will emit a low level “pisc” to communicate with their offspring at night.

For the most part, pottos communicate by scent, using glandular secretion to mark areas. They create urine trails and scent-mark paths that lure potential mates. This also provides clues to their reproductive state and fertility. The pottos’ unique scent has been described as “curry-like.”

Reproduction and Family
Male pottos have territory ranges that overlap with several females. This indicates that pottos have a polygynous family structure; one male mates with multiple females. This also implies that males can be involved in several social groups and fluctuate between them. Males do not remain with any one group or specific female after impregnating her. Thus, females are the primary caregivers for young, although males are not entirely absent during the first six months of an infant’s life.

Pottos perform a “love dance” prior to mating. When suitable partners meet, they mutually court each other. These seduction ceremonies involve licking, grooming with claws and teeth, and scent marking each other. To make it even more challenging, these rituals are typically performed while hanging upside down from a branch.

Breeding systems vary regionally within potto communities. Birth rates tend to be higher during the fruiting seasons, when there is abundant food available for weaning the young. Fruiting seasons vary from region to region in Africa, so different areas will see a higher number of potto births than others during certain times of the year. The average gestation period is about 197 days.

A female gives birth once a year. At birth, an infant potto weighs from 0.07-0.11 lbs (30-52 g). For the first 3-8 days after birth they cling to their mothers. Because they are not often carried, and must do the clinging themselves, baby pottos are significantly more developed than other primates during infancy.

The offspring are cared for by their mothers for roughly the first three months and are weaned starting at about 150 days after birth. They nurse during the day while she rests. They learn how to forage and feed themselves by observing their mothers. Self-feeding is, therefore, a culturally and socially learned behavior. Fathers sleep with the mothers until the infant is matured and independent, however they do not play an active role in care giving. Offspring become independent in about six to eight months, and become sexually mature at about 18 months old.

Bosman's potto, Perodicticus potto potto, a subspecies of the West African potto, Perodicticus potto

Ecological Role
Like any frugivore, pottos are important seed dispersers in the forest, which keeps plant reproduction stable. They have very few predators because not many land animals can climb to their level in the canopy and most African birds are diurnal (active during the day). However, they are a food source for the few species that are able to prey upon them. 

Conservation Status and Threats
Pottos are currently categorized by the International Union for Conservation of Nature as Near Threatened their annual Red List of Threatened Species (IUCN, 2020). There is generally not much research that has recorded the population patterns of wild pottos. 

Although the West Africa potto is still relatively widespread, its forest habitat is rapidly being destroyed and converted across a large part of its range. In the nine West African countries where the species is known to occur, forest cover over the last three generations (27 years, given a generation length of 9 years) has declined by more than 20%, while the human population has more than doubled.

The West African potto is increasingly hunted for food and is traded for traditional practices. Although data on declines in their populations are not available, due to an absence of systematic surveys, it is likely that the population has declined by at least 20% over the last three generations (27 years). This species is likely to qualify for the threatened category of Vulnerable in the near future.

Pottos and other nocturnal prosimians are impacted more harshly than diurnal creatures by deforestation. This is because they are usually asleep or resting when forests are cut down and burned, and they have little warning or time to escape. This, combined with their relatively slow locomotion and tendency to freeze when threatened, makes them susceptible to being burned or chopped down with trees. Unlike other members of the prosimian family, they are not hunted by human predators for the illegal pet trade.

Conservation Efforts
Pottos are listed under the Convention on International Trade in Endangered Species (CITES), which is an internationally recognized agreement between governments that aims to ensure that international trade between species does not threaten or endanger their survival. Pottos are carefully monitored under this convention to assure their population does not decline.

The potto is also protected under the African convention, which ensures its protection and only authorizes hunting and poaching of the species for specific reasons. Given their vast distribution, it is believed that there are several populations residing within protected national parks.

A large part of potto research is aimed towards studying newly found or debated species of pottos. Researchers believe there very well might be subspecies not yet found, or even subspecies that were never found that have gone extinct. More research will paint a clearer picture for the future of the potto and help classify the species as a whole.

References:

  • http://animaldiversity.org/accounts/Perodicticus_potto/
  • Oates, J.F., Butynski, T.M., Kingdon, J., Bearder, S., Pimley, E. & De Jong, Y. 2016. Perodicticus potto. The IUCN Red List of Threatened Species 2016: e.T91995408A91995190. http://dx.doi.org/10.2305/IUCN.UK.2016-
  • http://www.damisela.com/zoo/mam/primates/loridae/potto/index.htm
  • http://pin.primate.wisc.edu/factsheets/links/perodicticus_potto
  • Nekaris K.AI., Pimley E.R., Ablard K.M. (2007) Predator Defense by Slender Lorises and Pottos. In: Gursky S.L., Nekaris K.A.I. (eds) Primate Anti-Predator Strategies. Developments in Primatology: Progress and Prospects. Springer, Boston, MA
  • ​African Convention on the Conservation of Nature and Natural Resources (January, 2009) 
  • https://www.arkive.org/potto/perodicticus-potto/

Written by John DeVreese, April 2018