Francois' Langur
Encyclopedia
Francois' langur or Francois' leaf monkey (Trachypithecus francoisi) is a species of lutung
and the type species
of its species group
. Francois' langur belongs to the Colobinae
subfamily, Cercopithecidae family, in the Primates order. Of all of the colobine species, Francois' langur is the least studied of all of the species.
The species is distributed from Southwestern China to northeastern Vietnam
. Before 1990, Francois' Langur could be found in 23 different countries with a total population size of 2,000-2,500 individuals. There has been a dramatic decline in the population size by approximately 85% since then, making this species that of very high priority to potential extinction. The total number of wild individuals is unknown, but there are believed to be less than 500 left in Vietnam and 1,400-1,650 in China. There are only about 60 langurs in captivity in North American zoos.
The Mesker Park Zoo
in Evansville, Indiana
, has made headlines for its success in breeding the rare monkey
. The zoo received two females, Liang and Sai, in November 2003 from the San Diego Zoo
. Each gave birth to a son in August 2006. The father came from the Cincinnati Zoo in December 2005. In February 2008 Liang gave birth to a female.
In March 2009 an orange female was born at Australia's Taronga Zoo
. She is being cared for by zoo staff after being rejected by her mother.
http://www.cutebreak.com/?s=elke&submit.x=0&submit.y=0&submit=Submit+now
In September 2009 a female (GinLu) was born in the Lied Jungle at Omaha's Henry Doorly Zoo. After being rejected by her mother, Lied Jungle keepers worked for several weeks to teach the mother to feed and care for her properly. It was important to have a special holding area for mother and infant for safety, ensuring the family was within sight and smell at all times. Mother and infant needed to be strongly bonded before placing the group together. By October 13, 2009, the entire group was reunited into one holding area.
. It will also consume fruit
s (17.2%), seed
s, flowers, stem
s, root
s, bark
and occasionally mineral
s and insect
s off of rock surfaces and cliffs. This langur consumes its favorite food, young leaves, at the highest rate during the dry season, April through September, also known as the young leaf-lean period. The consumption of other dietary options for the langur is typically consumed in the highest amounts during the months of October through March.
Langurs not only prefer young leaves, but also have been found to prefer plants of only 10 different species: Pithecellobium clypearia, Ficus nervosa, Garcinia pauncinervis, Sinosideroxylon pedunculatum, F. microcarpa
, Miliusa chunni, Securidaca inappendiculata, Bauhinia
sp., and Canthium dicoccum
. Though these are the preferred plant species of the langur, it will still consume other plant species opportunistically.
Behavioral daily activities vary in the Francois' Langur. Most of its time is spent relaxing or sleeping and foraging
year around. Traveling, playing, grooming
and huddling are more dependent on the season. Interestingly it has been found that grooming happens in all of the seasons except the spring where it has been seen to not happen at all. Traveling is at its highest peak in the winter season, consuming 20.12% of its daily time budget. Lastly huddling is most prominent in the spring; it is most common to observe this langur spending approximately 14.62% of its time huddling.
Its preferred habitat is a karst topography
; limestone
cliffs and caves of tropical and subtropical zones. By living on these limestone cliffs, langurs are at an advantage when it comes to sleeping arrangements. Langurs sleep either on a ledge or in a cave, with its preference being in the cave. By living and sleeping in these limestone caves and cliffs, far from flat land, the langurs have greatly reduced their rate of predation. They exhibit cryptic behavior and become very vigilant upon entrance of the cave for final resting as a tactic to warn off any predators. In addition to this they also demonstrate a loud call to declare their territorial spacing. Francois' langurs will also choose their sleeping habitat depending upon foraging availability. They will choose sleeping sites that are close to potential foraging sites, to maximize energy and reduce travel costs. When they do go to forage they tend to travel along the same route and return to the same sleeping site for many consecutive nights to avoid predation.
Another threat to Francois' langur is the destruction of its habitat. The langurs live on limestone cliffs and when farmers look to cultivate their land they will light fires on the lower slopes. Limestone is particularly susceptible to fire; therefore this practice not only destroys their habitats but also causes major food shortages for the langurs because their diet is primarily folivorous. The primary predators of Francois' langur are both terrestrial and aerial. The Clouded Leopard
is a potential predator to the langur but the Clouded Leopard's numbers are so low that they are not their greatest threat. Aerial predators such as the Crested Serpent Eagle
and the Mountain Hawk-eagle are a greater threat to the Francois' langurs of Nonggang, especially to their young.
The actions being taken towards the conservation of these animals and their habitat is still minimal. Their current population size is less than 2,500 individuals. A plan to protect the forest and ban hunting, called the Conservation Action Plan, was drafted in 1996 but has still yet to be implemented. In order to protect the langurs, not only does protection from hunting need to be implemented but their habitats must be protected as well. In 2003, the National Forestry Bureau acknowledged the rapid decline in Francois' Langur and agreed to increase law enforcement in this area to help protect the langurs from hunters. In addition, the Asia Developmental Bank has begun helping the residents that live in close proximity to the habitats of the langurs build biogas facilities to reduce the fuel wood collection and thus possibly reduce the number of fires. And finally, a current project is underway by the Global Environmental facility to protect the Nonggang National and Dmingshan Natural Reserves and the langurs living within.
Lutung
The lutungs are a group of Old World monkeys and make up the entirety of the genus Trachypithecus. Their range is split into two parts; one part is much of southeast Asia , the other part is extreme southern India and Sri Lanka. The greater part of India has lutungs...
and the type species
Type species
In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
of its species group
Species group
A species group is an informal taxonomic rank into which an assemblage of closely related species within a genus are grouped because of their morphological similarities and their identity as a biological unit with a single monophyletic origin.-Use:...
. Francois' langur belongs to the Colobinae
Colobinae
Colobinae is a subfamily of the Old World monkey family that includes 59 species in 10 genera, including the skunk-like black-and-white colobus, the large-nosed proboscis monkey, and the gray langurs. Some classifications split the colobine monkeys into two tribes, while others split them into...
subfamily, Cercopithecidae family, in the Primates order. Of all of the colobine species, Francois' langur is the least studied of all of the species.
The species is distributed from Southwestern China to northeastern Vietnam
Vietnam
Vietnam – sometimes spelled Viet Nam , officially the Socialist Republic of Vietnam – is the easternmost country on the Indochina Peninsula in Southeast Asia. It is bordered by China to the north, Laos to the northwest, Cambodia to the southwest, and the South China Sea –...
. Before 1990, Francois' Langur could be found in 23 different countries with a total population size of 2,000-2,500 individuals. There has been a dramatic decline in the population size by approximately 85% since then, making this species that of very high priority to potential extinction. The total number of wild individuals is unknown, but there are believed to be less than 500 left in Vietnam and 1,400-1,650 in China. There are only about 60 langurs in captivity in North American zoos.
The Mesker Park Zoo
Mesker Park Zoo
The Mesker Park Zoo and Botanic Garden is a zoo that opened in 1928 in Evansville, Indiana. It is one of the oldest and largest zoos in the state...
in Evansville, Indiana
Evansville, Indiana
Evansville is the third-largest city in the U.S. state of Indiana and the largest city in Southern Indiana. As of the 2010 census, the city had a total population of 117,429. It is the county seat of Vanderburgh County and the regional hub for both Southwestern Indiana and the...
, has made headlines for its success in breeding the rare monkey
Monkey
A monkey is a primate, either an Old World monkey or a New World monkey. There are about 260 known living species of monkey. Many are arboreal, although there are species that live primarily on the ground, such as baboons. Monkeys are generally considered to be intelligent. Unlike apes, monkeys...
. The zoo received two females, Liang and Sai, in November 2003 from the San Diego Zoo
San Diego Zoo
The San Diego Zoo in Balboa Park, San Diego, California, is one of the most progressive zoos in the world, with over 4,000 animals of more than 800 species...
. Each gave birth to a son in August 2006. The father came from the Cincinnati Zoo in December 2005. In February 2008 Liang gave birth to a female.
In March 2009 an orange female was born at Australia's Taronga Zoo
Taronga Zoo
Taronga Zoo is the city zoo of Sydney, New South Wales, Australia. Officially opened on 7 October 1916, it is located on the shores of Sydney Harbour in the suburb of Mosman...
. She is being cared for by zoo staff after being rejected by her mother.
http://www.cutebreak.com/?s=elke&submit.x=0&submit.y=0&submit=Submit+now
In September 2009 a female (GinLu) was born in the Lied Jungle at Omaha's Henry Doorly Zoo. After being rejected by her mother, Lied Jungle keepers worked for several weeks to teach the mother to feed and care for her properly. It was important to have a special holding area for mother and infant for safety, ensuring the family was within sight and smell at all times. Mother and infant needed to be strongly bonded before placing the group together. By October 13, 2009, the entire group was reunited into one holding area.
Range and Distribution
Francois' langur has a restricted range of areas in which it can inhabit. It is primarily found in South West China and Northern Vietnam. A majority of the observations made on Francois' Langur take place in the Nonggang nature Reserve and the Fusui Nature Reserve in Guangxi Province, China. The average home range size of this species is 19ha and its day range size is 341-577m2. In general, the low quality of its folivorous diet leads to nutritional stress, a smaller home range size and reduced daily travel time. The largest group of langurs reported numbered 500-600 individuals, and was found in the Mayanghe National Nature Reserve. The Fusui nature Reserve reported in 2009 that Francois' langur population had declined 73% in the previous 5 years, thus lessening their distribution even more.Physical description
Francois' langur is a medium sized primate with black silky hair. It grows to be approximately 24 inches tall with a tail length of approximately 33 inches. The average weight for an adult Francois' langur is 13-15 lbs. It has very distinct white sideburns that grow down from its ears to the corners of its cheeks. A morphological specialization of Francois' langur is its complex stomach, made up of four separate chambers. This is a necessary adaptation for the digestion of its folivorous diet.Social structure
Francois' langur tends to live in groups of four to seven langurs, the mean being seven. "In [Francois] Langur society, females rule the roost and take the lead when the family is on the move" (BBC-Wild China, Episode 1). It lives in harem societies with a group consisting of one male, three females, and three offspring. Within the society, the females will share parenting responsibilities with one another and are philopatric to the group. Males within the group take no part in the raising of the young, the young males will leave the group before reaching sexual maturity.Behavior
Francois' langur is one of several species of leaf monkeys. Over 50% of its diet is made up of young leavesLeaves
-History:Vocalist Arnar Gudjonsson was formerly the guitarist with Mower, and he was joined by Hallur Hallsson , Arnar Ólafsson , Bjarni Grímsson , and Andri Ásgrímsson . Late in 2001 they played with Emiliana Torrini and drew early praise from the New York Times...
. It will also consume fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
s (17.2%), seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s, flowers, stem
Plant stem
A stem is one of two main structural axes of a vascular plant. The stem is normally divided into nodes and internodes, the nodes hold buds which grow into one or more leaves, inflorescence , conifer cones, roots, other stems etc. The internodes distance one node from another...
s, root
Root
In vascular plants, the root is the organ of a plant that typically lies below the surface of the soil. This is not always the case, however, since a root can also be aerial or aerating . Furthermore, a stem normally occurring below ground is not exceptional either...
s, bark
Bark
Bark is the outermost layers of stems and roots of woody plants. Plants with bark include trees, woody vines and shrubs. Bark refers to all the tissues outside of the vascular cambium and is a nontechnical term. It overlays the wood and consists of the inner bark and the outer bark. The inner...
and occasionally mineral
Mineral
A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...
s and insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...
s off of rock surfaces and cliffs. This langur consumes its favorite food, young leaves, at the highest rate during the dry season, April through September, also known as the young leaf-lean period. The consumption of other dietary options for the langur is typically consumed in the highest amounts during the months of October through March.
Langurs not only prefer young leaves, but also have been found to prefer plants of only 10 different species: Pithecellobium clypearia, Ficus nervosa, Garcinia pauncinervis, Sinosideroxylon pedunculatum, F. microcarpa
Ficus microcarpa
Ficus microcarpa, also known as Chinese Banyan, Malayan Banyan, Indian Laurel or Curtain fig, is a banyan native in the range from Sri Lanka to India, southern China, the Malay Archipelago, the Ryukyu Islands, Australia, and New Caledonia.-Taxonomy:Hill's Weeping Fig is a form of Ficus microcarpa...
, Miliusa chunni, Securidaca inappendiculata, Bauhinia
Bauhinia
Bauhinia is a genus of more than 200 species of flowering plants in the subfamily Caesalpinioideae of the large flowering plant family Fabaceae, with a pantropical distribution. The genus was named after the Bauhin brothers, Swiss-French botanists....
sp., and Canthium dicoccum
Canthium dicoccum
Psydrax dicoccos is a species of flowering plant in the Rubiaceae family. It is found from southeast China to tropical Asia.-External links:** World Conservation Monitoring Centre 1998. . Downloaded on 21 August 2007....
. Though these are the preferred plant species of the langur, it will still consume other plant species opportunistically.
Behavioral daily activities vary in the Francois' Langur. Most of its time is spent relaxing or sleeping and foraging
Foraging
- Definitions and significance of foraging behavior :Foraging is the act of searching for and exploiting food resources. It affects an animal's fitness because it plays an important role in an animal's ability to survive and reproduce...
year around. Traveling, playing, grooming
Social grooming
In social animals, including humans, social grooming or allogrooming is an activity in which individuals in a group clean or maintain one another's body or appearance. It is a major social activity, and a means by which animals who live in proximity can bond and reinforce social structures, family...
and huddling are more dependent on the season. Interestingly it has been found that grooming happens in all of the seasons except the spring where it has been seen to not happen at all. Traveling is at its highest peak in the winter season, consuming 20.12% of its daily time budget. Lastly huddling is most prominent in the spring; it is most common to observe this langur spending approximately 14.62% of its time huddling.
Its preferred habitat is a karst topography
Karst topography
Karst topography is a geologic formation shaped by the dissolution of a layer or layers of soluble bedrock, usually carbonate rock such as limestone or dolomite, but has also been documented for weathering resistant rocks like quartzite given the right conditions.Due to subterranean drainage, there...
; limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
cliffs and caves of tropical and subtropical zones. By living on these limestone cliffs, langurs are at an advantage when it comes to sleeping arrangements. Langurs sleep either on a ledge or in a cave, with its preference being in the cave. By living and sleeping in these limestone caves and cliffs, far from flat land, the langurs have greatly reduced their rate of predation. They exhibit cryptic behavior and become very vigilant upon entrance of the cave for final resting as a tactic to warn off any predators. In addition to this they also demonstrate a loud call to declare their territorial spacing. Francois' langurs will also choose their sleeping habitat depending upon foraging availability. They will choose sleeping sites that are close to potential foraging sites, to maximize energy and reduce travel costs. When they do go to forage they tend to travel along the same route and return to the same sleeping site for many consecutive nights to avoid predation.
Threats and Conservation
The population of Francois' langur has been on a steady decline for the past 30 years. Of the many factors threatening the survival of the Francois' langur today, hunting has had one of the largest impacts. In Nonggang, where Francois' Langur is most prevalent, the natives believe that the langur had medicinal values, and have hunted them to make wine out of their bones, which they believed could cure fatigue and rheumatism. In 1983, the estimated population of Francois' langur was 4,000-5,000. In the 1970s, hunting records recorded more than 1,400 langurs killed and in the 1980s more than 1,500 langurs were killed. Comparing these numbers it is evident how hunting had an enormous impact on Francois' Langur population.Another threat to Francois' langur is the destruction of its habitat. The langurs live on limestone cliffs and when farmers look to cultivate their land they will light fires on the lower slopes. Limestone is particularly susceptible to fire; therefore this practice not only destroys their habitats but also causes major food shortages for the langurs because their diet is primarily folivorous. The primary predators of Francois' langur are both terrestrial and aerial. The Clouded Leopard
Clouded Leopard
The clouded leopard is a felid found from the Himalayan foothills through mainland Southeast Asia into China, and has been classified as vulnerable in 2008 by IUCN...
is a potential predator to the langur but the Clouded Leopard's numbers are so low that they are not their greatest threat. Aerial predators such as the Crested Serpent Eagle
Crested Serpent Eagle
The Crested Serpent Eagle is a medium-sized bird of prey that is found in forested habitats across tropical Asia. Within its widespread range, there are considerable variations and some authorities prefer to treat several of its subspecies as completely separate species. In the past, several...
and the Mountain Hawk-eagle are a greater threat to the Francois' langurs of Nonggang, especially to their young.
The actions being taken towards the conservation of these animals and their habitat is still minimal. Their current population size is less than 2,500 individuals. A plan to protect the forest and ban hunting, called the Conservation Action Plan, was drafted in 1996 but has still yet to be implemented. In order to protect the langurs, not only does protection from hunting need to be implemented but their habitats must be protected as well. In 2003, the National Forestry Bureau acknowledged the rapid decline in Francois' Langur and agreed to increase law enforcement in this area to help protect the langurs from hunters. In addition, the Asia Developmental Bank has begun helping the residents that live in close proximity to the habitats of the langurs build biogas facilities to reduce the fuel wood collection and thus possibly reduce the number of fires. And finally, a current project is underway by the Global Environmental facility to protect the Nonggang National and Dmingshan Natural Reserves and the langurs living within.