Vietnamese orangutan

The **Vietnamese orangutan** (*Pongo hooijeri*), also known as the **mainland orangutan**, is a species of orangutan that originally lived in mainland Southeast Asia during the Pleistocene and was once extinct, but has since been brought back from extinction by SciiFii and reintroduced throughout the modern tropical rainforests, wetlands, forests, and open woodlands across Southeast Asia to help boost biodiversity. The Vietnamese orangutan resembles the orangutans of Borneo and Sumatra in appearance, habitat preference and behavior with a physical resemblance to the Tapanuli orangutans of northern Sumatra. Vietnamese orangutans display significant sexual dimorphism; females typically stand 115 centimeters (3 feet 9 inches) tall and weigh around 37 kg (82 lb), while flanged adult males stand 137 centimeters (4 feet 6 inches) tall and weigh 75 kg (165 lb). Compared to humans, they have proportionally long arms, a male orangutan having an arm span of about 2 m (6.6 ft), and short legs. Most of their bodies are covered in coarse hair that is generally red but ranges from bright orange to maroon or dark chocolate, while the skin is grey-black. Though largely hairless, males' faces can develop some hair, giving them a beard. Vietnamese orangutans favor lowland dipterocarp forests and old secondary forests with population densities at their greatest near sources of freshwater. Despite being adapted to an arboreal existence, Vietnamese orangutans, like some island orangutan populations, show tolerance of grasslands and forest clearings to a small degree. Vietnamese orangutans are primarily frugivores (fruit-eaters) and 57–80% of their feeding time is spent foraging for fruits. Even during times of scarcity, fruit can still take up 16% of feeding. Vietnamese orangutans prefer fruits with soft pulp, arils or seed-walls surrounding their seeds, as well as trees with large crops. Figs fit both preferences and are thus highly favoured, but they also consume drupes and berries. Vietnamese orangutans are thought to be the sole fruit disperser for some plant species including the vine species *Strychnos ignatii* which contains the toxic alkaloid strychnine. Vietnamese orangutans also supplement their diet with leaves, which take up 25% of their foraging time on average. Leaf eating increases when fruit gets scarcer, but even during times of fruit abundance, Vietnamese orangutans will eat leaves 11–20% of the time. The leaf and stem material of *Borassodendron* plants appears to be an important food source during low fruit abundance. Other food items consumed by the apes include bark, honey, bird eggs, insects and small vertebrates including the slow loris. Most of the day is spent feeding, resting, and travelling. They start the day feeding for two to three hours in the morning. They rest during midday, then travel in the late afternoon. When evening arrives, they prepare their nests for the night. The social structure of the Vietnamese orangutan can be best described as solitary but social; they live a more solitary lifestyle than the other great apes. Vietnamese orangutans are generally more solitary than Sumatran orangutans. Most social bonds occur between adult females and their dependent and weaned offspring. Resident females live with their offspring in defined home ranges that overlap with those of other adult females, which may be their immediate relatives. One to several resident female home ranges are encompassed within the home range of a resident male, who is their main mating partner. Interactions between adult females range from friendly to avoidance to antagonistic. The home ranges of resident males can overlap greatly, though encounters are relatively rare and hostile. Adult males are dominant over sub-adult males, the latter of which keep their distance. Vietnamese orangutans are invulnerable to most arboreal predators due to their large size and strength. However, if Vietnamese orangutans travel across the forest floor similar to Bornean orangutans, they could become possible prey for the Indochinese leopards, tigers and packs of dholes. Both the sun bear and Asiatic black bear are potential threats to young, infirm or weakened individuals. Vietnamese orangutans near large, continuous bodies of water are vulnerable to saltwater and Siamese crocodiles as well as reticulated pythons. The conservation status of the Vietnamese orangutans is **Vulnerable** due to some habitat loss and historic poaching, however, thanks to the conservationists, the Vietnamese orangutans are a protected species.