Black crested gibbon

Last updated

Black crested gibbon [1]
Temporal range: Pleistocene to Recent [2]
CITES Appendix I (CITES) [4]
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Primates
Suborder: Haplorhini
Infraorder: Simiiformes
Family: Hylobatidae
Genus: Nomascus
Species:
N. concolor
Binomial name
Nomascus concolor
(Harlan, 1826)
Subspecies
  • Nomascus concolor concolor
  • Nomascus concolor lu
  • Nomascus concolor jingdongensis
  • Nomascus concolor furvogaster
Black Crested Gibbon area.png
Black crested gibbon range
Synonyms

Hylobates concolor

The black crested gibbon (Nomascus concolor) is a Critically Endangered species of gibbon found in China, Laos, and northern Vietnam, with four subspecies.

Contents

Taxonomy

The taxonomy of the species is confused. Previously grouped in the genus Hylobates , currently four subspecies are recognised. [3]

Description

The length from the head to the end of body is 43–54 cm (17–21 in) and it weighs from 6.9 to 10 kg (15 to 22 lb). [5] The species exhibits sexual dichromatism, the male is completely black, while the female is a golden or buff colour with variable black patches, including a black streak on the head. [5]

Behavior

Gibbons are forest dwellers and are well known for their habit of swinging between the branches of the rainforest on their long arms, a method of locomotion known as brachiation. Gibbons are also adept, however, at walking upright, both on the ground and in the trees. Black crested gibbons live in small family groups consisting of a monogamous male and female and their offspring; occasionally groups reportedly may contain additional mature females. These apes are predominantly arboreal and the group forages and sleeps amongst the trees. Led by the female, the breeding pair partakes in vigorous bouts of singing in the morning, which hauntingly echo through the forest. These 'duets' are believed to be essential in pair bond formation and reinforcement, and also serve to advertise the presence of the group within the territory. A single young is born every two to three years and the infant is usually weaned once it reaches two years old;

Black crested gibbons feed preferentially on ripe, sugar-rich fruit, such as figs, but occasionally consume vitamin-rich leaf buds, and rarely eat animals.

Group living

Black-crested gibbons live arboreally in small groups, most of which consist of a pair of adults, one male and one female, and their offspring. It has been observed that some groups consist of one adult male living with two to four females and their offspring. The group could potentially include one infant, one juvenile, one adolescent, and one sub adult. [6] Groups have been found to be territorial, like other species of gibbons. Territories are limited by the availability of the male for territory defense. Thus, group and territory size would be limited. With a large group, territory defense would not be favored by kin selection due to the group consisting of less-closely related individuals. [7] Though the research is not explicit, there can be some assumptions made about altruism within groups. Since the majority of groups are living in monogamous relationships with both males and females displaying aggression when another individual enters, [7] it is likely that kin selection plays a major role in determining behavior of the group. Kin recognition is thought to be favored for maternal-offspring relationships. This is largely due to primates' uncertainty over paternity, even in pair-bonding species due to female promiscuity. [8] Social behaviors within groups will evolve according to Hamilton's rule. [9]

Mating

Gibbons were previously reported to practice monogamous sexual relationships. [7] They are known to form pair bonds, as well documented in the majority of gibbon species. [8] Upon the discovery of single male, multi-female living groups, the question arose to determine if all females were mating. The observation that offspring of similar ages lived within a multi-female group confirmed that polygyny did in fact occur. The current hypothesis remains that both monogamous and polygamous relationships exist. [6] There may be various selection pressures for polygyny within previously monogamous groups. Parents tend to be hostile towards maturing offspring, with males leaving the group more quickly than females do. [6] Yet, upon tolerance by the mother, adult female offspring may remain in the group, as the group continues to forage and feed as family members. The mutual tolerance of females is likely to be caused by "weak territoriality of females". [6] Further selection occurs due to the birth interval for a single female averaging 2–2.5 years. Male fitness would benefit from inseminating other females during a birth interval. [6] This hypothesis is supported by the large scrotal size allowing for increased sperm production. [6] Other observations have been made that males will share child carrying to place less of a burden on the female, delaying her interbirth time. [7] The conflicting observations support the hypothesis that black-crested gibbons demonstrate both monogamous and polygamous sexual relationships.

Singing

All gibbon species are known to produce loud and long song bouts, lasting for 10–30 minutes. The black-crested gibbon sings in the morning, sometimes in duets initiated by the male. The males choose the highest tree branches, often near ridges. The songs are thought to be used for resource defense, mate defense, pairbonding, group cohesion and mate attraction. [10]

Distribution and habitat

The black crested gibbon has a discontinuous distribution across southwestern China, northwestern Laos, and northern Vietnam. One thousand years ago, gibbons which may have been crested gibbons (Nomascus) were found over a large part of southern and central China up to the Yellow River. [3]

The four subspecies are geographically separated. The Tonkin black crested gibbon (Nomascus concolor concolor) occurs in southern China (southwestern Yunnan) and northern Vietnam (Lào Cai, Yên Bái, Sơn La, and Lai Châu provinces), between the Black and Red Rivers. The West Yunnan black crested gibbon (N. c. furvogaster) occurs in a small area near the Burma border, west of the Mekong, in southwestern Yunnan, southern China. The Central Yunnan black crested gibbon (N. c. jingdongensis) occurs in a small region around the Wuliang Mountains, between the Mekong and Chuanhe rivers in west-central Yunnan. The Laotian black crested gibbon (N. c. lu) occurs in northwestern Laos in an isolated population on the east bank of the Mekong in Laos. [3]

The black crested gibbon inhabits tropical evergreen, semievergreen, deciduous forests in subtropical and mountainous areas. It generally lives in high altitudes, from 2100 to 2400 m above sea level, where most of their food resources are concentrated. In Vietnam and Laos, the species is found at lower altitudes, while in China, it has been observed as high as 2689 meters. [5]

Conservation

The black crested gibbon is listed as critically endangered on the IUCN Red List. An estimated 1300 to 2000 individuals are left in the wild. [3] The western black crested gibbons were included on the State Forestry Bureau of China's list of 12 flagship and keystone species for biodiversity protection in 2021. [11] While under protection, there was still a noticeable decline in population size at Wuliangshan National Nature Reserve. [12] It was discovered that the gray langurs are suppressing the black crested gibbon's potential recovery. [12] The gray langurs and black crested gibbons have similar diets and ranges; however, gray langurs have an advantage by having a more comprehensive dietary list, a larger group, and faster life history. [12] The black crested gibbon inhabits the evergreen broad-leaved forests that take a long time to regenerate, making it challenging for the gibbons to connect with other groups. [13] Ecological corridors were put in place in the Hengduan Mountain in China to help restore connections between different groups, increase overall well-being, and decrease the risk of extinction. [13]

Related Research Articles

<span class="mw-page-title-main">Gibbon</span> Family of apes

Gibbons are apes in the family Hylobatidae. The family historically contained one genus, but now is split into four extant genera and 20 species. Gibbons live in subtropical and tropical rainforests from eastern Bangladesh to Northeast India to southern China and Indonesia.

<span class="mw-page-title-main">Red-shanked douc</span> Species of Old World monkey

The red-shanked douc is an arboreal and diurnal Old World monkey belonging to the Colobinae subfamily. They are endemic to Laos, Vietnam and Cambodia. They are known for their bright colors and exhibit sexual dimorphism through their body size. The species has been declared critically endangered by the International Union for Conservation of Nature, with the main threats being from hunting, habitat loss and pet trade. They are one of three species in the genus Pygathrix, the other two being the black-shanked and gray-shanked doucs.

<span class="mw-page-title-main">Lar gibbon</span> Species of ape

The lar gibbon, also known as the white-handed gibbon, is an endangered primate in the gibbon family, Hylobatidae. It is one of the better-known gibbons and is often kept in captivity.

<span class="mw-page-title-main">Pig-tailed langur</span> Species of Old World monkey

The pig-tailed langur, monotypic in genus Simias, is a large Old World monkey, endemic to several small islands off the coast of Sumatra in Indonesia. Its face is black, its fur is black-brown and it has a relatively short tail. It is a diurnal species, feeding in the rainforest canopy on leaves, and to a lesser extent, fruit and berries. Little is known of its natural history, but it is heavily hunted, its populations have been declining rapidly and the International Union for Conservation of Nature has assessed its conservation status as being "critically endangered". It has been included on a list of the World's 25 Most Endangered Primates.

<i>Hylobates</i> Genus of apes

The genus Hylobates is one of the four genera of gibbons. Its name means "forest walker", from the Greek hūlē and bates.

<i>Nomascus</i> Genus of apes

Nomascus is the second-most speciose genus of the gibbon family, Hylobatidae. Originally, this genus was a subgenus of Hylobates, with all individuals considered to be one species, H. concolor.

<span class="mw-page-title-main">Pygmy slow loris</span> Species of primate

The pygmy slow loris is a species of slow loris found east of the Mekong River in Vietnam, Laos, eastern Cambodia, and China. It occurs in a variety of forest habitats, including tropical dry forests, semi-evergreen, and evergreen forests. It was originally classified within Nycticebus until it was transferred to the genus Xanthonycticebus in 2022. Two species are recognised, the northern pygmy loris X. intermedius from northern Vietnam, Laos and China and the southern pygmy loris X. pygmaeus from southern Vietnam, Laos and Cambodia. The animal is nocturnal and arboreal, crawling along branches using slow movements in search of prey. Unlike other primates, it does not leap. It lives together in small groups usually with one or two offspring. An adult can grow to around 19 to 23 cm long and has a very short tail. It weighs about 450 g (1.0 lb). Its diet consists of fruits, insects, small fauna, tree sap, and floral nectar. The animal has a toxic bite, which it gets by licking a toxic secretion from glands on the inside of its elbows. The teeth in its lower jaw form a comb-like structure called a toothcomb that is used for scraping resin from tree bark.

<span class="mw-page-title-main">Eastern black crested gibbon</span> Species of Old World monkey

The eastern black-crested gibbon, also known as the Cao-vit black crested gibbon or the Cao-vit crested gibbon, is a species of gibbon from southeast China and northern Vietnam. The term "Cao-vit" originated from the sounds of their calls or songs that villagers of Ngoc Khe, Phong Nam and Ngoc Con communes of Trung Khanh District, Cao Bang Province of Vietnam use to name for them. This name was officially used by gibbon experts since the rediscovery.

<span class="mw-page-title-main">Gray-shanked douc</span> Species of Old World monkey

The grey-shanked douc langur is a douc species native to the Vietnamese provinces of Quảng Nam, Quảng Ngãi, Bình Định, Kon Tum, and Gia Lai. The total population was estimated at 550 to 700 individuals in 2004. In 2016, Dr. Benjamin Rawson, Country Director of Fauna & Flora International's Vietnam Programme, announced a discovery of an additional population including more than 500 individuals found in Central Vietnam, bringing the total population up to approximately 1000 individuals.

<span class="mw-page-title-main">Delacour's langur</span> Species of Old World monkey

Delacour's langur or Delacour's lutung is a critically endangered species of Old World monkey endemic to northern Vietnam. It is named for French-American ornithologist Jean Théodore Delacour.

<span class="mw-page-title-main">Yellow-cheeked gibbon</span> Species of Old World monkey

The yellow-cheeked gibbon, also called the golden-cheeked gibbon, the yellow-cheeked crested gibbon, the golden-cheeked crested gibbon, the red-cheeked gibbon, or the buffed-cheeked gibbon, is a species of gibbon native to Vietnam, Laos, and Cambodia. The species was discovered and named after the British naturalist Gabrielle Maud Vassal.

<span class="mw-page-title-main">Northern white-cheeked gibbon</span> Species of Old World monkey

The northern white-cheeked gibbon is a Critically Endangered species of gibbon native to South East Asia. It is closely related to the southern white-cheeked gibbon, with which it was previously considered conspecific. The females of the two species are virtually indistinguishable in appearance.

<span class="mw-page-title-main">Wildlife of Laos</span>

The wildlife of Laos encompasses the animals and plants found in the Lao People's Democratic Republic, a landlocked country in southeastern Asia. Part of the country is mountainous and much of it is still clad in tropical broadleaf forest. It has a great variety of animal and plant species.

<span class="mw-page-title-main">Hainan black crested gibbon</span> Species of Old World monkey

The Hainan black-crested gibbon or Hainan gibbon, is a Critically Endangered species of gibbon found only on Hainan Island, China. It was formerly considered a subspecies of the eastern black crested gibbon from Hòa Bình and Cao Bằng provinces of Vietnam and Jingxi County in Guangxi Zhuang Autonomous Region, China. Molecular data, together with morphology and call differences, suggest it is a separate species. Its habitat consists of broad-leaved forests and semi-deciduous monsoon forests. It feeds on ripe, sugar-rich fruit, such as figs and, at times, leaves, and insects.

<i>Ficus neriifolia</i> Species of fig tree from Asia

Ficus neriifolia is a species of fig (Ficus). It is native to Asia, including Bhutan, Burma, China, India, and Nepal.

<span class="mw-page-title-main">Southern white-cheeked gibbon</span> Species of Old World monkey

The southern white-cheeked gibbon is a species of gibbon native to Vietnam and Laos. It is closely related to the northern white-cheeked gibbon and the yellow-cheeked gibbon ; it has previously been identified as a subspecies of each of these.

<span class="mw-page-title-main">Myanmar snub-nosed monkey</span> Species of Old World monkey

The Myanmar snub-nosed monkey or Burmese snub-nosed monkey or black snub-nosed monkey is a critically endangered species of colobine monkey discovered in 2010 in northern Burma (Myanmar). It was formally described as a novel species of primate in 2011 based on its fur, beard and tail. Two groups of the species were discovered in China in 2011 and 2015, respectively.

<span class="mw-page-title-main">Northern buffed-cheeked gibbon</span> Species of primate

The northern buffed-cheeked gibbon is a newly discovered species of crested gibbon which is found in Vietnam, Cambodia, and Laos. Its habitat is in the humid subtropical and seasonal tropical forests of these countries.

Infanticide in non-human primates occurs when an individual kills its own or another individual's dependent young. Five hypotheses have been proposed to explain infanticide in non-human primates: exploitation, resource competition, parental manipulation, sexual selection, and social pathology.

<span class="mw-page-title-main">Primate sociality</span>

Primate sociality is an area of primatology that aims to study the interactions between three main elements of a primate social network: the social organisation, the social structure and the mating system. The intersection of these three structures describe the socially complex behaviours and relationships occurring among adult males and females of a particular species. Cohesion and stability of groups are maintained through a confluence of factors, including: kinship, willingness to cooperate, frequency of agonistic behaviour, or varying intensities of dominance structures.

References

  1. Groves, C. P. (2005). "Order Primates". In Wilson, D. E.; Reeder, D. M (eds.). Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Johns Hopkins University Press. p. 180. ISBN   978-0-8018-8221-0. OCLC   62265494.
  2. "Fossilworks: Nomascus concolor". www.fossilworks.org.
  3. 1 2 3 4 5 Pengfei, F.; Nguyen, M.H.; Phiaphalath, P.; Roos, C.; Coudrat, C.N.Z.; Rawson, B.M. (2020). "Nomascus concolor". IUCN Red List of Threatened Species . 2020: e.T39775A17968556. doi: 10.2305/IUCN.UK.2020-2.RLTS.T39775A17968556.en . Retrieved 19 November 2021.
  4. "Appendices | CITES". cites.org. Retrieved 14 January 2022.
  5. 1 2 3 Cheng, Clarence (2011). Sargis, Eric; McCormick, Gale (eds.). "Nomascus concolor". Animal Diversity Web . Retrieved 29 December 2011.
  6. 1 2 3 4 5 6 Jiang, Xuelong; Wang, Yingxiang; Wang, Qiang (1999). "Coexistence of Monogamy and Polygyny in Black-crested Gibbon (Hylobates concolor)". Primates. 40 (4): 607–611. doi:10.1007/BF02574835. S2CID   40358103.
  7. 1 2 3 4 Brockelman, Warren Y. (2009). "Ecology and the Social Systems of Gibbons". In Lappan, Susan; Whittaker, Danielle J. (eds.). The Gibbons: New Perspectives on Small Ape Socioecology and Population Biology. Developments in Primatology: Progress and Prospects. pp. 211–239. ISBN   978-0387886039.
  8. 1 2 Silk, Joan B. (August 2002). "Kin Selection in Primate Groups". International Journal of Primatology. 23 (4): 849–875. doi:10.1023/A:1015581016205. S2CID   16441513.
  9. Silk, Joan B. (2006). "Practicing Hamilton's rule: kin selection in primate groups". In Kappeler, P.M.; van Schaik, C.P. (eds.). Cooperation in Primates and Humans: Mechanisms and Evolution. pp. 25–46. doi:10.1007/3-540-28277-7_2. ISBN   978-3-540-28269-3.
  10. Fan, Peng-Fei; Xiao, Wen; Huo, Sheng; Jiang, Xue-Long (2009). "Singing behavior and singing functions of black-crested gibbons (Nomascus concolor jingdongensis) at Mt. Wuliang, central Yunnan, China". American Journal of Primatology. 71 (7): 539–547. doi:10.1002/ajp.20686. PMID   19434673. S2CID   45664166.
  11. Fan, Peng-Fei; Zhang, Lu; Yang, Li; Huang, Xia; Shi, Kai-Chong; Liu, Guo-Qing; Wang, Chun-Hua (18 March 2022). "Population recovery of the critically endangered western black crested gibbon (Nomascus concolor) in Mt. Wuliang, Yunnan, China". Zoological Research. 43 (2): 180–183. doi:10.24272/j.issn.2095-8137.2021.390. ISSN   2095-8137. PMC   8920850 . PMID   35008133.
  12. 1 2 3 Chen, Yuan; Ma, Chi; Yang, Li; Guan, Zhenhua; Jiang, Xuelong; Fan, Pengfei (1 August 2020). "Asymmetric competition between sympatric endangered primates affects their population recovery". Biological Conservation. 248: 108558. doi:10.1016/j.biocon.2020.108558. ISSN   0006-3207. S2CID   225472295.
  13. 1 2 Wu, Jiacheng; Delang, Claudio O.; Li, Yijie; Ye, Quan; Zhou, Jie; Liu, Huan; He, Hongming; He, Wenming (1 September 2021). "Application of a combined model simulation to determine ecological corridors for western black-crested gibbons in the Hengduan Mountains, China". Ecological Indicators. 128: 107826. doi: 10.1016/j.ecolind.2021.107826 . ISSN   1470-160X.