Western tarsier
The Western tarsier, also known as Horsefield's tarsier, is a small primate native to the islands of Indonesia, particularly in Borneo, Bangka, and southern Sumatra. These nocturnal creatures are characterized by their distinctive features, including large, saucer-shaped eyes and thin, elongated ears. Despite their impressive eye size, which outweighs their small brain, Western tarsiers rely on acute hearing for hunting at night. They are primarily insectivorous but also consume small vertebrates such as lizards, bats, snakes, and birds, demonstrating a capacity to prey on animals larger than themselves.
Measuring between 4.5 to 6 inches in body length and weighing around 4 to 5 ounces, these agile animals live in pairs or small family groups and are known for their remarkable ability to leap from branch to branch. The species has a gestation period of about 178 days, typically resulting in the birth of one young, which is weaned after 80 days. However, the Western tarsier faces threats from habitat loss due to human activities, leading to its classification as a vulnerable species. With an average lifespan ranging from eight to 17 years, they play a unique role in their ecosystem, warranting interest and conservation efforts.
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Western tarsier
Western tarsiers are primates found on islands throughout Indonesia. Although most tarsiers eat only insects, Western tarsiers also eat lizards, bats, snakes, and birds. They have been known also to kill and eat animals that are much larger than themselves. Western tarsiers are also known as Horsefield's tarsiers.
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Family: Tarsiidae
Genus: Cephalopachus
Species: Bancanus
Western tarsiers are small and monkey-like, with short brownish gray fur, large, saucer-shaped eyes and thin cylinder-like ears. The eyes of the western tarsier are so large compared to the rest of its body that each eye weighs more than its whole brain (which weighs about three grams). Although they have very large eyes, they are not able to move them from side to side the way people can move their eyes. Western tarsiers rely mainly on their excellent hearing ability to hunt prey during the night. Western tarsiers have thin legs and bony skeletal feet and hands. Their feet have very sharp nails for digging and catching prey. Western tarsiers, like all tarsiers, have the ability to twist their heads half way around to see whatever is behind them.
Western tarsiers grow to a head and body length of between 4 1/2 and six inches (11 1/2 to 15 centimeters) and have eight- to nine-inch (20 to 23 centimeter) tails. They weigh between four and five ounces (122 to 134 grams).
Western tarsiers usually live in pairs or in small family groups in the forests of Borneo, Bangka, and southern Sumatra. They are nocturnal, which means they sleep during the day and are active during the night. Western tarsiers, like other tarsiers, are good at leaping from branch to branch.
Western tarsiers are carnivores, or meat-eating animals. Western tarsiers eat both insects and small animals, and drink water from pools and streams. Their diet includes gnats, mosquitos, dragonflies, moths, termites, locusts, and grasshoppers. They also eat lizards, bats, snakes, and birds. Western tarsiers will even kill birds and snakes that are larger than themselves. It is possible that snakes would prey upon tarsiers as well, but this rarely happens. Scientists believe that tarsiers are able to lower their body temperature when they are asleep. Since snakes find their prey by sensing body heat, the western tarsiers are safe.
Mating season for western tarsiers takes place throughout the year but western tarsiers only breed once a year. During mating season western tarsiers chase one another through the trees and then mate in the trees. The gestation period (duration of pregnancy) is about 178 days. The female western tarsier then gives birth to one young tarsier. The young are weaned after 80 days.
Cats, lizards, snakes, owls, and large birds may prey on the western tarsier. Western tarsiers have an average life span of at least eight years but sometimes up to 17 years. Due to the loss of their habitat from human activities, the western tarsier is a vulnerable species.
Bibliography
“Horsfield's Tarsier - Facts, Diet, Habitat, & Pictures on Animalia.bio.” Animalia, 2024, animalia.bio/horsfields-tarsier/1000. Accessed 6 May 2024.
McKeighan, Paul. “ADW: Tarsius Bancanus: Information.” Animal Diversity Web, 2011, animaldiversity.org/accounts/Tarsius‗bancanus. Accessed 6 May 2024.