PYGMY SLOW LORISES

pygmy slow loris

Pygmy slow lorises (Nycticebus pygmaeus) are found in tropical areas in forests and rainforests at elevations up to 1500 meters (4920 (high) feet) in Vietnam, Laos, eastern Cambodia, and neighboring regions of southern China (southeast Yunnan province). It not known whether those in China are native or introduced. In Vietnamese folklore, pygmy slow lorises are called "khi gio", or "monkeys that move with the wind." They believe the animals portend bad fortune and are used for black magic. [Source: Margaret Gray, Animal Diversity Web (ADW) /=]

Pygmy slow lorises do well in degraded habitats, rainforests and bamboo thickets in Vietnam and evergreen forest in Laos. Locals in the Mondulkiri province of Cambodia suggest that pygmy slow lorises prefer thick, complex forested areas with bamboo to dry dipterocarp forest, and observations confirm their preference of mixed deciduous to semi-evergreen forests. Individuals of this species are usually seen at heights of three to 12 meters in the canopy.

Pygmy slow lorises are primarily insectivores (mainly eat insects) but can also be described as herbivores (eat plants or plants parts), frugivores (eat fruits) omnivores (eats a variety of things, including plants and animals). Animal foods include eggs, insects. Among the plant foods they eat are fruit nectar flowers sap or other plant fluids. They also eat fungus. Pygmy slow lorises develop fat stores by increasing their feeding and choosing more energy-rich foods in the last few weeks of autumn. These fat stores are useful during the food scarce winter months.

Margaret Gray wrote in Animal Diversity Web: Reports from local people of Cambodia suggest pygmy slow lorises eat mostly termites, tree parts, fruit, and bamboo. Though surveys confirm they do eat this variety of foods, the absolute preference for termites over the other foods is not clear. There is also great debate over the degree of insectivory in this species. Some suggest that insects make up approximately 33 percent of their diet, while others state that they are frugivorous. Although early accounts of the species indicate that members of this species eat insects, lizards, eggs, and "anything edible" in addition to fruit, recent studies do not corroborate these observations. /=\

At the Endangered Primate Rescue Center, captive pygmy slow lorises are offered fruit, vegetables, boiled eggs, milk powder, and insects, and the insects are the most readily accepted food item. Captive animals also gouge fresh tree branches, indicating a preference for exudates. They have been observed licking Saraca dives, Sapindus and Vernicia montana trees for periods between one and 20 minutes. Pygmy slow loris scratch and break the bark of other species of trees, feeding on the gum.

Pygmy Slow Loris Characteristics

Zoologist J.L. Harrison describes pygmy slow lorises as "rather like a child's teddy-bear." They range in weight from 120 to 500+ grams (4.2 to 16 ounces), with an average weight is 400 grams (14.10 ounces) and range in length from 15 to 25 centimeters (5.91 to 9.84 inches). Sexual Dimorphism (differences between males and females) is present: Males are larger than females. . Pygmy slow lorises can slow their growth if environmental conditions are not good. If their diet is restricted, they lose their juvenile fur and attain adult dentition before attaining adult size. Pygmy slow lorises and Bengal slow lorises evolved from a common ancestor and look similiar. The smaller body size in pygmy slow lorises is thought to be the result their geographic location. [Source: Margaret Gray, Animal Diversity Web (ADW) /=]

pygmy slow loris

Pygmy slow lorises have thick light brown to deep reddish brown fur with a white or gray underside. According to Animal Diversity Web: Individuals have a unique pattern of lighter and darker colored markings on their face, which commonly include circles around the eyes and dorsal stripes starting at their crown and continuing down their back. During the winter, these markings become more prominent, and they acquire silver tips or "frosting." This seasonal coloration is thought to camouflage and protect the animals, as, during the winter, they must sit in exposed areas such as dense scrub or in the upper branches of trees that lack foliage. /=\

Like other strepsirhine primates and members of the family Lorisidae, pygmy slow lorises have: forward-facing eyes with stereoscopic vision; a rhinarium, the moist naked surface around the nostrils; a tapetum lucidum, the reflective layer in the eye that improves night vision; a split upper lip; nails on all digits except for a grooming claw on the second digit of their feet; a dental formula of 2. 1. 3. 3/ 2. 1. 3. three with the lower incisors and canines forming a toothcomb (a group of teeth with fine spaces between them); no tail; and reduced second digits on their hands.

Pygmy slow lorises produce a toxin from modified sweat glands located near their elbows. They have been observed licking theses glands when alarmed. Their bite can be dangerous to humans; the only account of a pygmy slow loris biting a human resulted in an adult woman entering anaphylactic shock. They also hibernate. Hibernation is the state that some animals enter during winter in which normal physiological processes are significantly reduced, thus lowering the animal's energy requirements. The home ranges of pygmy slow lorises are not known. /=\

Pygmy Slow Loris Behavior

Pygmy slow lorises are arboreal (live mainly in trees), nocturnal (active at night), motile (move around as opposed to being stationary), solitary, territorial (defend an area within the home range). In Sunda slow lorises, type of habitat affects the size of a home range, which is highly variable. There is broad overlap between ranges of Sunda slow lorises. [Source:Margaret Gray, Animal Diversity Web (ADW) /=]

Pygmy slow lorises are quadrupedal (use all four limbs for getting around), with grasping hands and feet. Margaret Gray wrote in Animal Diversity Web: They walk along branches hand over foot, stretching from one branch to the next. Their strong grip allows them to hang by their feet and gather food with both hands or to stand bipedally then throw their upper body forward to pounce on prey. Pygmy slow lorises almost exclusively remain in trees, except on rare occasions in response to potential predators. /=\

Pygmy slow lorises are thought to move almost constantly during the night hours of warmer months. Members of this species are commonly referred to as "slow lorises" due to the speed of their movement, but observations made at the Duke Lemur Center indicate that their movement is actually faster than other species of slow loris. During cold winter months, pygmy slow lorises are capable of entering a state of torpor and living off their fat reserves. They reduce their activity, lower their metabolic rate and body temperature, and do not forage. This hibernation-like behavior is observed both in the wild and in captivity. /=\

Because pygmy slow lorises have only rarely been studied in the wild, many aspects of their behavior are still unknown. While they are generally considered solitary, pygmy slow lorises are occasionally characterized as "gregarious" due to their mating behavior. A species that spends over 50 percent of its time with members of their own species is classified as gregarious. However, currently no scientific study has confirmed this potentially gregarious nature. The territory of one male often overlaps with the territory of several females, leading to polygynous mating behavior and more frequent social behavior in males. /=\

Pygmy slow lorises sense using vision, touch, sound and chemicals usually detected with smell. They communicate with sound and chemicals usually detected by smelling and scent marks produced by special glands and placed so others can smel. They utilize a variety of verbal communications. When disturbed, they growl and hiss. They issue a rising tone during general contact and may whistle to the opposite sex during estrus. Mothers softly chirp to their infants, who respond with rapid clicks and squeaks when they are in distress. Males mark their territory with urine, which also affects mating behavior.

Pygmy Slow Loris Reproduction and Parenting

Pygmy slow lorises are polygynous (males have more than one female as a mate at one time). They engage in seasonal breeding and breed once every 12 to 18 months. Pygmy slow lorises generally breed from end of July to the beginning of October. The number of offspring ranges from one to two, with the average number being two. Although a single offspring is usually born, twins are common with this species. [Source: Margaret Gray, Animal Diversity Web (ADW) /=]

Although mating has been observed in captivity, little to nothing is known about mating of pygmy slow lorises in the wild. According to Animal Diversity Web: Female pygmy slow lorises enter estrus between July and October. During this period, the female vagina and male testes become enlarged. Behavior also differs during this period; females are more likely to approach others and engage in lunging, while males are more likely to sniff and lick a female's genitals and mount them. /=\

A male's territory typically includes several females with whom he mates. Males and females communicate with one another through whistles. Olfactory cues are also used to find mates. Males spread their scent through urination, and males thus produce more urine than females. Males that spread their scent over a large area have a competitive advantage, because marking territory is an indication of health, persistence, and energy. Females prefer males with a familiar odor to males they have not previously encountered, which may be related to infrequent contact between the sexes. /=\

The average gestation period is six months and births generally take place during the winter months.. The weaning age ranges from four to eight months. The average weaning age is 4.5 months. On average females reach sexual or reproductive maturity at age nine months; and males do so at 18 to 20 months. . Birthing occurs in the open, and infants are born fully formed with fur and open eyes. Offspring are nursed for an average of 4.5 months, though in some cases weaning may take as long as eight months. Females reach sexual maturity at about nine months of age, while males reach sexual maturity at 18 to 20 months of age.

Immediately after birth, pygmy slow lorises cling to their mother's underside. Later, mothers exhibit "parking" behavior, leaving their infants in a safe location while they leave to forage for food. Without the burden of a dependent, mothers can more efficiently gather food for themselves and their offspring. Individuals in the San Diego Zoo have a similiar parenting style to that of other species of slow lorises. However, pygmy slow lorises spend more time in close proximity to their young, tending to huddle, sit or stand within 0.3 meters of their offspring more than other species. Mothers and infants primarily establish closeness through passive ventral contact. Although mothers do not appear to directly defend their young, they tolerate the following behavior of their young as they get older. As infants age, they engage more often in adult social behaviors such as grooming and play, and less often in huddling and ventral contact.

Pygmy Slow Lorises, Humans and Conservation

On the International Union for Conservation of Nature (IUCN) Red List pygmy slow lorises are listed as Vulnerable; US Federal List: classifies them as Threatened. In CITES (Convention on International Trade in Endangered Species of Wild) they are in Appendix I, which lists species that are the most endangered among CITES-listed animals and plants. Pygmy slow lorises were listed in Appendix II in February 1977 but promoted to Appendix I in September 2007, which indicates trade of this species has not been properly controlled in the last few decades. Populations decreased by 30 percent between 1984 and 2008, and they continue to decline. [Source:Margaret Gray, Animal Diversity Web (ADW) /=]

Margaret Gray wrote in Animal Diversity Web Humans are the primary predators of pygmy slow lorises. Their prevalence in Cambodian and Vietnamese markets testifies to the intense hunting pressure on this species. Camobodian locals report hunting pygmy slow loris as a "non-target species," suggesting that the rate of hunting is not affected by abundance and will continue even as these animals become more scarce. Pygmy slow lorises are easy prey because of their tapetum lucidum, the reflective layer in the eye that improves night vision, which glows when a spotlight is shone in their direction and by some accounts incapacitates them. This makes this species an easy target for night hunters.

Pygmy slow lorises are commonly used in medicines in Cambodia. In Phnom Penh, they are found in local markets roasted, dried, and made into pre-mixed medicines with rice-wine, alcohol, honey, or charcoal. Doctors of traditional medicine reported in questionnaires that these medicines are primarily used to treat "women after childbirth, stomach problems, wounds, broken bones, and sexually transmitted diseases". In the 1950s from Myanmar (Burma) to Borneo, the fur of slow lorises was used to dress wounds and cuts because of its blood clotting properties, and it may still be used as such in some localities. Some researchers attribute the popularity of loris medicine to the lack of access to or education about biomedical alternatives and high levels of poverty. /=\

Due to increased protection of this species, market price is increasing. Veteran hunters able to distinguish different species of loris and know species distributions in local forests yield high profits. Trade is driven by wealthy city dwellers who are able and willing to pay rural hunters for their illegal product. /=\

Live trade of slow lorises occurs in high levels in the Mondulkiri, Ratanakiri, and Phnom Penh provinces of Cambodia. As many as 204 lorises were found in a single store in Phnom Penh. Slow lorises are the most popular pets that are listed on CITES Appendix I. They are primarily traded in Borneo, Java, Sumatra, and the surrounding islands. Live trade of slow lorises most commonly affects Sunda slow lorises, Bornean slow lorises, and Javan slow lorises, but traders do not distinguish among species, and other slow lorises such as pygmy slow lorises are sometimes traded as well. This lack of differentiation among species leads to hybridization, improper care and health problems, as well as reintroduction of confiscated animals into improper habitat.

Lorises are frequently killed by logging and slash and burn agriculture. If they are not killed in the fire, they face habitat destruction, which may lead to their eventual disappearance from the area. The resulting fragmentation of forests further threatens the species. Populations of pygmy slow lorises drastically declined during the Vietnam War, as bombing, land clearing by Rome plows, and use of Agent Orange (2,4,5-T), other defoliants, and napalm destroyed the majority of their native habitat in Vietnam, Laos, and Cambodia. Bombing is estimated to have damaged 40 percent of Vietnamese forests, and herbicides affected 43 percent of the cultivated area. Prior to the Vietnam War, broad-leafed tropical forests with stands of bamboo and mangroves covered approximately one-half of the land area in these countries.

Although trade is restricted and capture and transport of pygmy slow lorises are illegal in all countries in their range, their small size makes slow lorises easy to traffic in boxes, baskets, and sacks from country to country. This process is physically stressful for the animals and also threatens their health. Rescue centers have been developed for confiscated slow lorises, but mortality rates remain high. These deaths are attributed to trauma, disease, and atypically close proximity to members of their own species. /=\

Image Sources: Wikimedia Commons

Text Sources: Animal Diversity Web animaldiversity.org ; National Geographic, Live Science, Natural History magazine, David Attenborough books, New York Times, Washington Post, Los Angeles Times, Smithsonian magazine, Discover magazine, The New Yorker, Time, Reuters, Associated Press, AFP, Lonely Planet Guides, Wikipedia, The Guardian, Top Secret Animal Attack Files website and various books and other publications.

Last updated December 2024