BORNEAN YELLOW MUNTJACS
Bornean yellow muntjacs (Muntiacus atherodes) as their name suggests are found throughout the island of Borneo, which is shared by Malaysia and Indonesia. They live in variety of habitats, including moist forests, low hills, rainforests, scrub forests, coastal regions, and areas of dense vegetation. They tend to live near a reliable water source at elevations from zero to 1200 meters (3937 feet). [Source: Ashley Jetzer, Animal Diversity Web (ADW) /=]
Morphology suggests that muntjacs likely evolved from tufted deer (the only extant species of Elaphodus) and that the most primitive muntjacs were most similar to the extant Bornean yellow muntjac, which were not recognized as a distinct species until 1982. They were previously considered a subspecies of Southern red muntjac (Indian muntjacs), and were known by the name Muntiacus pleiharicus. Besides difference in physical appearance, Bornean yellow muntjacs and Southern red muntjacs can be distinguished from each other by their skulls. Bornean yellow muntjacs have smaller skulls, a relatively deep preorbital pit, and reduced frontal ridges. Bornean yellow muntjacs are the only muntjac species that lack an orange occipital patch. /=\
The International Union for Conservation of Nature (IUCN) Red List classifies Bornean yellow muntjacs as a species of “Least Concern”. In CITES (Convention on International Trade in Endangered Species of Wild) they have no special status. However that doesn’t mean there are np threats. Bornean yellow muntjacs are hunted for their skins and meat and regarded as crop pests and are sometimes killed for that reason. They are attracted to grazing areas near roads and in forest cuts, where they are easier targets for hunting than in the deep forest. Their primary known natural predators are clouded leopards.
See Separate Articles: MUNTJACS (BARKING DEER): CHARACTERISTICS, BEHAVIOR, SUBSPECIES factsanddetails.com ; MUNTJAC SPECIES factsanddetails.com
Bornean Yellow Muntjac Characteristics and Diet
Bornean yellow muntjacs They range in weight from 13 to 18 kilograms (28.6 to 39.6 pounds) and range in length from 90 to 100 centimeters (35.4 to 39.4 inches). Sexual Dimorphism (differences between males and females) is present: Ornamentation is different. Males have slender, simple horns of 1.6 to 4.2 centimeters (0.6 to 1.6 inches) in length. Males lack both frontal tufts of hair and antler burrs. Females have small, bony knobs and tufts of hair in place of horns. Males also have modified upper canines that curve strongly outward from the lips, forming small tusks.
Bornean yellow muntjacs have yellowish-orange fur. They have a darker stripe on the nuchal region which becomes yellowish-orange on the sides and then whitish on the belly. The tail has a dark nuchal stripe and the pale ventral color and is 14 to 20 centimeters (5.5 to 7.8 inches) in length. The under part of the throat retains the ventral paleness. The ears are sparsely haired with coloration ranging from deep brown to yellowish or grayish brown with creamy or whitish markings. At birth, fawns possess lines of white spots on the upper parts of their bodies. These spots remain until they are half their adult size. /=\
Bornean yellow muntjacs are primarily herbivores (eat plants or plants parts) but are also considered folivores (eat leaves) and frugivores (eat fruit). Among the plant foods they eat are leaves, wood, bark, stems, seeds, grains, nuts, fruit, shoots, grasses and herbs. They feed throughout the day. /=\
Bornean Yellow Muntjac Behavior and Communication
Little is known about the behavior of Bornean yellow muntjacs. They are terricolous (live on the ground), diurnal (active during the daytime), motile (move around as opposed to being stationary), sedentary (remain in the same area) and solitary. They lift their feet high when walking and are often seen in pairs consisting of an adult male and an adult female, they are occasionally seen alone . /=\
Bornean yellow muntjacs sense and communicate with vision, sound and chemicals usually detected by smelling. According to Animal Diversity Web: Muntjacs, in general, are known as ‘barking deer’ due to the short, sharp, loud, and deep bark-like call they produce. When alarmed, the barking of Bornean yellow muntjacs can last for more than an hour. The frequency of barking increases in circumstances of reduced visibility. A short, high-pitched mewing sound is emitted by females with young . Muntjacs also use the secretions from their pre-orbital glands to communicate reproductive state, territorial boundaries, and to cement social bonds. /=\
Bornean Yellow Muntjac Mating, Reproduction and Offspring
Little is known about mating in Bornean yellow muntjacs. Their mating systems and behavior is largely inferred the behavior of similar, better studied, species of muntjacs. Based on this it is surmised that Bornean yellow muntjacs are polyestrous and breed throughout the year, with males competing for access to females in estrous. /=\
The estrus cycle of Bornean yellow muntjacs lasts between 14 and 21 days. The gestation period is between 210 and 215 days. Typically a single fawn is born, very rarely twins. Female Bornean yellow muntjacs can have several offspring each year, depending on the availability of high quality nutrition. They lactate and protect their young.
Like other muntjacs, Bornean yellow muntjac young are relatively well-developed when born and develop rapidly. During the pre-weaning stage provisioning and protecting are done by females. Fawns stay hidden in thick vegetation until they are able to move about with its mother . The average weaning age is two months, about halfway into the next pregnancy, which is conceived just a few days after a fawn is born. . Females and males reach sexual or reproductive maturity at six to 12 months.
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 January 2025