Genus: Trachypithecus (formerly Presbytis)
Trachypithecus francoisi, better known as the Francois Langur can be found in Southeatern Asia: from Southeastern China to Central Laos and Vietnam. They tend to be both arboreal and terrestrial. Most of their habitats lay deep in the rainforests or mangroves, but some can be found among rocky cave areas.
The francois Langurs are easily identified due to their all black fur and white side burns. They are small monkeys that usually weigh approximately 13 pounds. Their bodies measure to be around two feet long with an additional three feet of tail. Francois Langurs are extremely athletic, using brachiation as their method to get from one food source to another. Their tails are not prehensile, but they do assist in helping with the langurs balance. The Francois Langur’s diet consists mostly of leaves with a small percentage of fruits, nuts, and insects. Due to their intensive-leaf diet, they have a multichambered sacculated stomach that helps digest the tough leaves! Since digesting leaves is such a complicated and tiring process, the langurs spend most of their free time resting (when not eating,) and a small percentage of the time in between grooming one another.
The Francois Langur was first noted by M. Francois of the French Consul in Lung Chow, China. He first noticed the langurs on the rocky shores between Nanning and Kuohua. The San Fransisco’s Zoo’s Francois Langurs was originally a gift from the People’s Republic of China.
Francois Langurs are not born with their notable black fur. Newborn langurs have bright red/orange fur, and they do not fully change until they are about one year old. The Francois Langurs travel together in a troop that consists of one alpha male, a “harlem” of females, and several infants. All females partake in raising the infants. Around three weeks old, the newborns are handed over to an “aunt” while the mother forages for food. At times female langurs can be seen carrying three infants, and not one will be her own. The troop engages in mutual grooming periods throughout the day when they are not resting and foraging for food.
“The morning of August 20 started out like any other morning at the Memphis Zoo for myself and another China Exhibit Keeper, arriving early, unlocking buildings, checking on animals and morning training sessions for Ya Y and Le Le. However, when we went to do our morning check on our Francois Langurs, we soon discovered that instead of the usual seven in our collection, we now had eight! Tanah, mother of three of our juveniles, had given birth to another little girl. Tanah is an experienced mother and knew exactly what to do. Our last two langurs born here in China were both given names that refer back to some super heroes of our time: “Bruce Wayne” and ” Vicki Vale.” With that in mind, we thought our new little girl was pretty super as well and deserved a name that reflected that. We named her “Jean Gray” from the X-Men series. She is super and doing great. She is currently on display with the rest of her family in China. When you come out to see her, she won’t be hard to miss. Francios Langur babies are bright orange. All the females in the group take turns caring for her and carrying her around.” – Quote from the Memphis Zoo.
The group communicates with a loud “ka” call that is emitted by the male as a type of alarm to signal danger. At the Honolulu Zoo in Hawaii, their alpha male produces a Geiger counter-type click in response to his reflection in the mirror; they suspect this to be a response to a territorial threat.
The Francois Langurs are an endangered species. They face many threats but the biggest one is hunting. Especially in Vietnam, the langurs are hunted for the use of traditional “medicines,” and also for food in Chinese restaurants. In the Guangxi Province of China, hunting has become extremely severe because of the production of “Black Ape Wine.” The wine is made specifically from the Francois Langur species, and the langurs are even imported illegally from Vietnam for this very reason.