The Delacour’s Langur

The Delacour’s langur, aka Delacour’s lutung, hails only from Vietnam in the Van Long Nature Reserve in Ninh Bình. They prefer open forest habitats with a predominant amount of limestone karst. Sadly, due to habitat destruction at the hands of mining and quarrying; hunting; trapping; and human-based recreational activities, these primates are listed as Critically Endangered by the IUCN. Their populations are also decreasing.

First the Stats…

Scientific name: Trachypithecus delacouri

Weight: Up to 23 lbs.

Length: Up to 24 inches, plus up to a 3.5 inch tail

Lifespan: Up to 20 years

Now on to the Facts!

1.) As of 2015, there were only an estimated 250 wild individuals remaining.

2.) Although they look similar, these langurs are slightly larger than their 2 closest relatives, the François’ langur and the Laotian langur.

3.) They can be found at about 1,076 foot elevations.

4.) Delacour’s langurs are diurnal (active during the day).

5.) Being folivores (eat leaves) and frugivores (eat fruit) their diet consists of various leaves, seeds, fruit, and flowers.

But wait, there’s more on the Delacour’s langur!

6.) They take refuge in limestone caves. However, if there are no caves available, they will sleep on bare rocky surfaces.

7.) Before their populations were so decimated, these primates would gather into troops of up to 30+ individuals. Nowadays they can sometimes be seen in troops of just up to 16 members.

Did you know…?

There are approximately 19 known individuals in captivity. Conservation efforts are under way to try and repopulate the species. The Van Long Nature Reserve populations may still be large enough to remain viable. But that is uncertain.

8.) When faced with rivals, the dominant male will utilize intimidation tactics such as physical displays and loud hoots. If these don’t work, they will chase down and even fight their rivals.

9.) Within the troop, social bonding is maintained via play and social grooming.

10.) These critters are mostly terrestrial (spend their lives on the ground), even though they live in forested areas.

But wait, there’s still more on the Delacour’s langur!

11.) Females undergo up to a 200 day gestation (pregnancy) that yields a single infant.

12.) Infants are born precocial (self sufficient) and with orange fur that turns black as they age.

13.) The infants are weaned at around 21 months old.

Now a Short Delacour’s Langur Video!

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Some source material acquired from: Wikipedia & IUCN

Photo credit: Nguyen Van Truong.