Life span: >30 years
Total population: approx. 300,000
Regions: South Asia
Gestation: 200 days
Height: 61.1 to 68.9 cm (M & F)
Weight: 12.5 to 17.7 kg (M & F)
Species: S. ajax, S. dussumieri, S. entellus, S. hector, S. hypoleucos, S. priam, S. schistaceus
Other names: Hanuman langur, sacred langur, Indian langur; S. ajax:
dark-eyed Himalayan langur, Himalayan gray langur, Kashmir gray langur, western
Himalayan langur; S. dussumieri: Dussumier's Malabar langur, southern
plains gray langur; S. entellus: Bengal hanuman langur, common langur,
entellus langur, gray langur, Hanuman langur, northern plains gray langur, true
langur; Hanuman langur (Danish); hoelman (Dutch); hulmaani (Finnish); entelle;
houleman (French); hulman (German); langur, hanuman (Hindi); entello (Italian);
gooni (Kumaun Hindi); houlemán, langur común, langur hanuman
(Spanish); grå hulman, hanumanlangur, himalayahulman, hulman,
hulmanbladapa (Swedish); S. hector: gray langur, Hanuman langur, lesser
hill langur, Tarai gray langur; S. hypoleucos: black-footed gray
langur, dark-legged Malabar langur; S. priam: Madras gray langur,
tufted gray langur; S. schistaceus: central Himalayan langur, Nepal
The taxonomy of the gray langur is debated, and until recently, all gray langurs
were subsumed under one species, S. entellus, or included as subspecies
of S. entellus (Bennett & Davies 1994; Groves 2005). In some cases
the species is still considered monotypic with different populations separated
out subspecifically. Groves (2005) recognizes 7 species and his taxonomy is
The gray langur is sometimes referred to as the Hanuman langur, named after the
monkey-god Hanuman. As such, gray langurs are considered sacred in the Hindu
religion (Roonwal & Mohnot 1977).
Photo: Kamal Kumar Dua
In general, gray langurs are large monkeys but vary greatly in body size
between species and location (Roonwal & Mohnot 1977; Bennett & Davies
1994). A rough gradient of decreasing size and mass exists as one moves further
south in the gray langur distribution (Roonwal 1981; Napier 1985; Ray 2000). In
addition, there is variation in the degree of sexual dimorphism, with some
species showing profoundly larger males than females, while others show only
nominal differences (Groves 2001). The overall body color of all species is
grayish with a black face and ears, and a tail that is always longer than the
body (Roonwal & Mohnot 1977; Roonwal 1981; Groves 2001). Northern and
southern populations of gray langur differ in their method of carrying their
tail, with northern populations carrying their tail pointed forward, while
southern populations do so with the tail pointed backwards (Roonwal 1979;
Roonwal et al. 1984). The dividing line between the two populations is roughly
along a line across the Indian peninsula (Roonwal et al. 1984).
S. ajax is very large in body size. It has a yellowish-white
coloration, especially on the ventrum and some brown on the dorsum and limbs
with the forelimbs darkest (Groves 2001; Brandon-Jones 2004). S.
dussumieri is one of the smaller gray langurs and is gray-brown or mauve
with a yellowish ventrum and is one of the smaller gray langurs. The upper
hindquarters are whitish and the head is creamy colored. The fingers and toes
are black and sometimes the extremities and forearms are also. Overall, S.
entellus has a reddish or orangish tinge, with yellow sides and a brownish
or gray-brown back (Groves 2001; Brandon-Jones 2004). Body size is around
average for the gray langurs (Brandon-Jones 2004). The belly is red-gold
(Groves 2001). S. hector has a white head and is overall grayish
yellow, yellowish-white, or pale orange with brownish limbs, a grayish-brown
back and a whitish ventrum with pale paws (Groves 2001; Brandon-Jones 2004).
S. hypoleucos is a mid-sized gray langur and is purplish-brown with
black limbs and an orangish belly. In addition, the body hair is longer than
that on the limbs, and the tail is black (Groves 2001). S. priam is
pale brown-gray, with a whitish head and a creamy yellow ventrum (Groves 2001;
Brandon-Jones 2004). The body is mid-sized for a gray langur (Brandon-Jones
2004). The hands and feet are lighter than the body, the tail has a white end
and the feet are sometimes almost white (Groves 2001). S. schistaceus
are mid-sized gray langurs that dark brownish with a whitish head, ventrum,
upper hindquarters, and tip of the tail. Further, they have a larger body size
than others among the gray langurs (Groves 2001).
The combined head and body lengths of both sexes of S. schistaceous average
68.9 cm (27.1 in) but females are typically somewhat smaller than males. Males
average 17.7 kg (39.0 lb) and females average 15.8 kg (34.8 lb) (Roonwal 1979).
S. ajax with both sexes have a combined head and body length that
averages 67.1 cm (26.4 in) and weigh on average 17.7 kg (39.0 lb). S.
entellus average 63.9 cm (25.2 in) and weigh an average of 12.5 kg (27.6
lb). The head and body length of S. priam averages 61.1 cm (24.1 in)
and average 12.8 kg (28.2 lb) (Roonwal 1981).
Gray langurs move primarily in a quadrupedal fashion both terrestrially and
arboreally, about half of the time in each mode (Ripley 1967; Sugiyama 1976;
Vogel 1977). Running is preferred to walking, both on the ground and in the
trees, although both are seen. Other forms of locomotion include bipedal hops,
climbing and descending supports with the body upright, and leaping (Ripley
1967; Dunbar & Badam 1998). Horizontal leaps may be 3.7-4.6 m (12.0-15.0
ft), while descending leaps may be up to 10.7-12.2 m (35-40 ft) (Ripley 1967).
Further, when moving terrestrially at a medium speed, gray langurs will
sometimes intermittently walk then run several steps, each in an irregular
pattern (Grand 1976). Gray langurs have been seen swimming after accidentally
falling into water (Agoramoorthy 1986).
In captivity, gray langurs can live into their early thirties, and in the
wild males may live past 18 years old and females past 30 (Borries et al. 1991;
P. Dolhinow pers comm. cited in Sommer et al. 1992; Rajpurohit et al. 1995;
Weigl 2005). In captivity, females can be reproductively active well into their
late 20s (P. Dolhinow pers comm. cited in Sommer et al. 1992).
CURRENT RANGE MAPS (IUCN REDLIST):Semnopithecus ajax
| Semnopithecus dussumieri
| Semnopithecus entellus
| Semnopithecus hector
| Semnopithecus hypoleucos
| Semnopithecus priam
| Semnopithecus schistaceus
Among the colobines, gray langurs have the widest distribution, found in
Bangladesh, Bhutan, China, India, Nepal and Pakistan; ranging from north India
in Kashmir and the Himalayas in Nepal, Bhutan, and Tibet south to Sri Lanka,
east to Bangladesh and west to the Indus valley in Pakistan (literature reviewed
in Roonwal & Mohnot 1977; Rajpurohit 1992; Wang et al. 1999; literature
reviewed in Ray 2000; Groves 2001; Brandon-Jones et al. 2004; Choudhury 2008).
Gray langurs may exist in Afghanistan as well (Brandon-Jones 2004).
Among the species, S. ajax is found between the Himalayas in
northern India and Pakistan. S. dussumieri is found throughout
west-central and southwestern India. S. entellus ranges between
lowland Pakistan in the west and the Godavari and Krishna Rivers in central
India and north to the Ganges River. S. hector ranges from northern
India in Kumaun near the western border of Nepal to Katmandu in central Nepal,
restricted to the Himalayan foothills. S. hypoleucos is only found in
the Kerala coastal region of southwestern India. S. priam is found on
the island of Sri Lanka as well as on the mainland of southeastern India.
Finally, S. schistaceus ranges in the Himalayas from central Nepal to
Tibet near Mount Everest to areas of China near northwest Bhutan (Groves
Gray langurs are flexible in their habitat choice and, correspondingly, are
found in a large range of habitat types and environments (Sugiyama 1976;
Oppenheimer 1977; Bennett & Davies 1994). They range from arid habitats to
tropical evergreen rainforests, including all forest types excepting dense rain
forest and range higher than 4000 m (13123.4 ft) above sea level including areas
that receive winter snows. Other habitats include evergreen forest, moist
deciduous forest, broadleaf forest, subtropical pine forest, riverine forest,
dry open scrub, open park woods, desert areas, mountain foothills, mountain
forests, Himalayan oak-coniferous forests, dry deciduous habitats, subtropical
evergreen forest, temperate coniferous forest, sub-alpine forest, grasslands,
meadows, scrub, scrub forests, mixed grasslands and forest, moist deciduous
habitats and even villages, towns, residential areas, tourist areas, temple
grounds orchards and areas under cultivation (Sugiyama 1976; reviewed in Vogel
1977; Bishop 1979; Roonwal 1981; Curtin 1982; Mathur & Manohar 1990; Newton
1992; reviewed in Bennett & Davies 1994; Mathur & Manohar 1994; Pirta et
al. 1997; Chaudhuri et al. 2004; Rajpurohit et al. 2004). They are rarely found
in evergreen forests (Bennett & Davies 1994). They adapt well to habitats
in close proximity to humans, living even in built-up areas including markets
(Bennett & Davies 1994). In fact, gray langurs inhabit the city of Jodhpur,
India, a city of over a million inhabitants (Waite et al. 2007). The rainfall
in their habitats also varies greatly; from under 10 cm (3.9 in) annual
precipitation to over 200 cm (78.7 in) (Oppenheimer 1977). Among the species,
S. dussumieri is found in moist deciduous forest, dry scrub forest, dry
scrub desert, dry deciduous forest and tropical broadleaf forests. S.
schistaceus is found in temperate coniferous and broad leaf forests
(reviewed in Kirkpatrick 2007). S. ajax is found in temperate
oak-coniferous forests which encounter snowfalls during the winter (Oppenheimer
Photo: John Oates
Himalayan populations experience strong seasonality in their habitat between
cold winters (temperatures can fall as low as 19.4 °F (-7 °C)) and
rainy summer monsoons (Bishop 1979; Curtin 1982). In contrast, at a different
long-term study site at the Kumbhalgarh Wildlife Sanctuary in Rajasthan, India,
summer temperatures usually range between 30 and 35 °C (86 and 95 °F)
and as high as 46 °C (114.8 °F) while during the winter average
temperatures are around 5 °C (41 °F) and can get as cold as 2 °C
(35.6 °F). Average rainfall is 72.5 cm (28.5 in) at this study site
Gray langurs are mostly vegetarian but are not exclusively leaf-eating like
some colobines (Vogel 1977). Over their distribution, gray langurs have
variable diets by location, habitat type, as well as season and receive
differing levels of provisioning by humans. In natural, non-provisioned
populations, the diet is composed of leaves (52-61%), fruits (15-25%), flowers
(4-13%), insects (0.4-3%), and other foods such as bark, gums, and soils (9-16%)
(reviewed in Koenig & Borries 2001). A variety of plant foods and species
are eaten across species (over 200), including deciduous and evergreen leaves,
as well as leaf buds, herb leaves, coniferous needles, fruits, fruit buds and
evergreen petioles (reviewed in Roonwal & Mohnot 1977; reviewed in Vogel
1977; Khan 1984; Chalise 1994-1995; Sayers & Norconk 2008). Trees and
shrubs predominate, followed by herbs and grasses and finally other plant types
(reviewed in Vogel 1977). Other foods which are consumed include shoots, seeds,
mosses and lichens, coniferous cones, underground plant parts, spider webs,
termite mounds, cremated human remains and bones, fern rhizomes, grass, bamboo,
plants under cultivation, such as potatoes, spinach, cauliflower, cotton,
eggplant and radishes, and provisioned foods given by humans, such as wheat
cakes, millet, and other human foods (reviewed in Oppenheimer 1977; reviewed in
Roonwal & Mohnot 1977; Khan 1984; Sayers & Norconk 2008). Gray langurs
sometimes drink water, but not from leaves in trees or muddy water (Oppenheimer
1977; reviewed in Roonwal & Mohnot 1977; Starin 1978; Newton 1992).
However, most water is attained from the food they ingest (Starin 1978).
Rarely, resins are eaten (Newton 1992). In general, gray langurs are not picky
and if a food is available and suitable, a gray langur will eat it (Koenig &
Borries 2001). Usually, more mature leaves are eaten than young leaves (Koenig
& Borries 2001). Bark is eaten mostly in times of food scarcity and rarely
at other times (Sharma 2001).
Gray langur diets change seasonally as well with shifts in food abundance.
This is the case with the population (probably S. schistaceus) in the
Langtang National Park, Nepal (Sayers & Norconk 2008). At this highly
seasonal location, low-abundance winter (December-March) foods include leaf
buds, ripe fruit, and the fallback food of evergreen mature leaves. During
spring (April-May) food includes largely deciduous young leaves and bark.
Summer monsoon foods (June-September) include deciduous mature leaves and
fruits. Fall (October-November) foods include deciduous mature leaves, unripe
fruit, and herbs, and underground plant parts (Sayers & Norconk 2008). With
seasonal changes in availability otherwise less-important foods can also become
more important, as is the case with insects during the monsoon (Srivastava
1991). In one study, the consumption of insects approached almost a quarter of
feeding time at the beginning of the yearly monsoon at a study site in central
India (Newton 1992).
Photo: Kamal Kumar Dua
Gray langurs are diurnal, spending their nights in sleeping trees (usually
more than two near to one another) in one study averaging around 12 m (39.4 ft)
tall, usually selecting the highest branches (Ramakrishnan & Coss 2001;
Chhangani 2002b). In less natural habitats, gray langurs have used old hunting
towers or high-tension electric poles for sleeping (Sharma 2002).
On an annual basis in undisturbed forest in the central Indian highlands,
gray langurs spend their time feeding (25.7%), idle (41.8%), moving (13.1%),
clinging (7.9%), and allogrooming (6.0%) (Newton 1992). In Bangladesh, near the
eastern limits of their distribution, gray langurs spend their days sitting
(44.3%), moving (16%), feeding,(14%), playing (11.2%), social grooming (7.1%)
and the rest of the day in other activities (Ahsan & Khan 2006). Himalayan
gray langurs in Nepal spent their time feeding (39.8%), resting (29.2%),
traveling (17.5%), grooming (9.5%), and huddling (3.2%) with the rest of their
time spent in other activities (Sayers & Norconk 2008). However, there are
seasonal shifts in activities, as is the case at Ambagarh Reserve Forest,
Jaipur, India, where summer activities are concentrated in the morning and
afternoon while in the winter most activity is at midday (Mathur & Bhatnagar
1993). Gray langurs do not follow a consistent daily regimen (Rajpurohit &
Rajpurohit 2002). In addition, under provisioning, gray langurs become less
active (Rajpurohit & Rajpurohit 2002).
Home ranges, like other aspects of gray langur ecology are also quite
variable; from 0.07 to 22 km² (0.03 to 8.5 mi²) with the home ranges of all male
groups typically larger than those of other types (Mathur & Manohar 1993;
literature compiled by Chhangani & Mohnot 2006). Long-term data indicate
that groups usually do not alter or move their home ranges (Newton 1994).
Himalayan gray langurs (probably S. schistaceus) travel an average of
1.5 km (0.9 mi) each day annually with the longest traveled days during the
winter (Sayers & Norconk 2008).
In some areas, wild cattle and deer wait under arboreally feeding gray
langurs and eat foods dropped by the primates (Punekar 2002). Further, nymphs
of the insect Leptocoris augur may rely on langurs to crack the hard outer
casings of preferred fruits and congregate below langur feeding locations to
feed (Newton 1984).
Gray langurs live sympatrically with a number of other primates across their
distribution, including Macaca sp.
and Trachypithecus johnii (Singh et al. 2000;
Ramakrishnan & Coss 2001; Choudhury 2008; Vasudev et al. 2008). Close
associations between Himalayan populations of gray langurs and rhesus macaques
(Macaca mulatta) have been seen, and a female langur has even been seen suckling
an infant rhesus macaque (Das & Sharma 1980).
Predators of gray langurs include leopards (Panthera pardus), dholes (Cuon
alpinus) and tigers (P. tigris) (Boggess 1976; Ross 1993; Andheria et al. 2007).
Wolves (Canis lupus) may be a predator, as may be golden jackals (Canis aureus)
(Boggess 1976; Newton 1985). Upon sighting snakes, gray langurs have been seen
to mob the reptiles (Srivastava 1991).
Content last modified: October 28, 2008
Written by Kurt Gron.
Cite this page as:
Gron KJ. 2008 October 28. Primate Factsheets: Gray langur (Semnopithecus) Taxonomy, Morphology, & Ecology . <http://pin.primate.wisc.edu/factsheets/entry/gray_langur/taxon>. Accessed 2014 September 17.