One of the rarest monkeys in the world, the Hainan black-crested gibbon, or Hainan gibbon, is a unique and beautiful creature. The world’s last group of Hainan gibbons live in the tropical forests in China’s southern island province of Hainan.
The Duets
A male Hainan gibbon is eating fruits from the tree. /CGTN Photo
Every early morning, the harmonious duets of the Hainan gibbons echo in the lush rainforest of the Bawangling National Nature Reserve. The male leads the call, and its howling sound lingers in the forest up to several kilometers away. Then the females and youngsters join in with their low chattering.
A mother Hainan gibbon is carrying her child while swinging on the trees. /CGTN Photo
Listening to the calls of these gibbons is the main method for researchers to identify and quantify the gibbon population here. These gibbons are timid and vigilant animals, so it is extremely hard to observe them up close.
A male Hainan gibbon sitting on a branch. /CGTN Photo
The Hainan gibbon usually practices polygamy and forms a small family that consists of one male, two females and their offspring. The unique call of the male gibbon is considered to be both a way to bond with its family, and a demonstration of its rightful territory.
Lover’s look
The Hainan gibbon exhibits a sexual dimorphism, which is a condition where the two sexes of the same species exhibit different characteristics beyond the differences in their sexual organs.
The female Hainan gibbon has golden hair. /CGTN Photo
The male is completely black, and the female has bright golden hair with a black crest on the head to match with its male counterpart.
This lovely match is a result of up to two times of changing its hair color. A newborn is typically golden, with a thin black line on the center of its head. At six months old, the golden hair turns black starting from the shoulder and back.
Close up of a male Hainan gibbon. /CGTN Photo
When it reaches sexual maturity around six years old, a male would stop changing color and remain black, while the female would gradually change back to gold. It takes about a year for the female to change back to this color.
Current protection status
A young Hainan gibbon hidding among the leaves. /CGTN Photo
The population of the Hainan black-crested gibbon has largely decreased in the 1970s due to habitat loss. The government then established the Bawangling National Nature Reserve to connect the fragmented habitats of the species. Since 1989, the Hainan black-crested gibbon has been under first-class state protection in China.
(Cover photo designed by CGTN's Li Yueyun. Photos and videos courtesy of CGTN Nature film crew.)
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