Gibbons are apes that look like monkeys, but have no tails. There are various species of gibbon around the world. However, there are only two species of gibbon in Karen State: the Eastern Hoolock Gibbon and White-Handed Gibbon (Hylobates lar). In Karen State, the Eastern Hoolock Gibbon can be found in the area west of the Salween River and east of the Koh Loh River. The White-Handed Gibbon can be found in the area to the south-east of the Salween River.
Differences between the Eastern Hoolock Gibbon and the White-Handed Gibbon
There are some differences between these two gibbon species. The Eastern Hoolock Gibbon is smaller in size; the males are black and the females are yellow. Both male and female White-Handed Gibbons can be either black or white in color.
Population
The Eastern Hoolock Gibbon population in Karen State is small: only around one hundred gibbons remain. For the White-handed Gibbon, the population level is unknown, because no research has been done on this species in Karen State. However, it is estimated that their population is not more than 200.
Both of these gibbon species are protected by the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) against over-exploitation through international trade, and are listed as endangered species in the International Union for Conservation of Nature’s (ICUN) Red List.
Habitat, behavior and reproduction
Gibbons usually inhabit mountains with forest cover, especially those with a lot of plant species, many plants with new leaves emerging, and many pine trees. The Eastern Hoolock Gibbon usually lives on mountains between 800 and 2700 meters high. The White-Handed Gibbon usually lives on evergreen mountains not higher than 1200 meters.
Gibbons eat various kinds of leaves, flowers, seeds, tree bark, and tender plant shoots.
Gibbons love each other very much. Mated pairs live together like human wives and husbands, and do not separate. They live with their children as a family. A group of gibbons lives within defined boundaries, and they do not usually cross these boundaries and into other group’s territory. In the morning, gibbons usually call out in a loud voice, which is one of their communication methods.
Female gibbons are usually pregnant for seven months before they deliver their babies. The interim period between pregnancies is usually two to three years. Gibbons mostly have only one baby at a time. They take care of the baby until it is five or six years old. Young gibbons fully grow and mature when they reach eight or nine years old.
Eastern Hoolock Gibbons can live up to 25 or 30 years. However, some that have been captured and raised as domestic pets have lived up to 40 years. The average life expectancy of the White-Handed Gibbon is 30 to 40 years in the wild, and 45 years for those raised by people as domestic pets.
Threats to Gibbons in Karen State
Nowadays, the habitats of these gibbons are disappearing due to mining, logging and large-scale plantation projects. These projects have invaded their habitats. Moreover, the gibbons have been hunted for their meat and for medical purposes. Therefore, with their habitats being destroyed and the gibbons under threat from hunters, we can say for sure that these gibbon species will be gone in the near future. If people do not respect and value the forest habitats of the gibbons, and if the government does not develop and pass policies and laws that will protect these wild animals, we will not have a chance to see them in the future, not only in Karen State, but also in the whole of Burma/Myanmar.
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