Hylobates moloch
Creators: name: Russell A. Mittermeier
name: Anthony B. Rylands
name: Don E. Wilson
Publisher: name: Lynx Edicions
Year: 2013
Subjects: Biodiversity
Taxonomy
Animalia
Chordata
Mammalia
Primates
Hylobatidae
Hylobates
Hylobates moloch

description: 7.
Moloch Gibbon
Hylobates moloch
French: Gibbon cendré / German: Silbergibbon / Spanish: Gibon plateado
Other common names: Javan Gibbon, Silvery Javan Gibbon
Taxonomy. Simia moloch Audebert, 1798,
Indonesia, Java. Restricted by H. Sody in 1949 to WJava, Mt. Salak.
Although it has been suggested that there is evidence for two genetically distinct populations leading to the subsequent recognition of two subspecies by some authors, a review of the molecular evidence and a comparison of morphological and vocal data casts doubt on this claim. The central Javan form, pongoalsoni, said to be characterized by a black cap, may be a distinct subspecies, or it may simply be a morph, because black caps may also occur in western Java. Monotypic.
Distribution. Java, mainly in W provinces (Banten and West Java), with an additional population in a small area in the C as far E as the Dieng Mts.
Descriptive notes. There are no specific body measurements available; weight 6-6 kg (males) and 6-2 kg (females). Fur of the Moloch Gibbon is very long and uniformlysilvery-gray. It has a blackish face and at least a trace of black on the cap and chest. There is a poorly expressed light face-ring and a short white beard on the chin, and eyebrows are pronounced. The crown hairis directed fanwise from the front of the scalp and is somewhat elongated over the ears. The teeth are notably larger than in other species, with large cingula, unreduced third molars and, frequently, supernumerary cusps. The silvery gray color, the relatively large teeth, and its calls (non-duetting with simple note repetition) are consistent differences that distinguish it from other gibbons.
Habitat. Primary lowland and lower montane rainforest up to 2400 m above sea level (but normally below 1600 m). Moloch Gibbons prefer floristically rich patches of relatively undisturbed forest, but they can tolerate moderate disturbance.
Food and Feeding. Diets of Moloch Gibbons consist mainly offruits (61%) and leaves (38%), and they eat some flowers and insects.
Breeding. Interbirth intervals of Moloch Gibbons are typically 3-3-5 years, and sexual maturity of males and females occurs at 8-10 years of age. Age at first reproduction may be 10-12 years. Infants are creamy with a slight hint of a facial ring and a pink face, and the natal coat darkens rapidly to adult coloration. A female Moloch Gibbon lived to 50 years of age at the Winnipeg Zoo, Canada.
Activity patterns. There is no specific information available for this species, but it is diurnal and arboreal.
Movements, Home range and Social organization. Home ranges of Moloch Gibbons are 17-60 ha, most of which is defended. In general, males are aggressive toward other males and also defend their territory from external threats. Females lead the group’s daily progressions and keep away other females. It is believed that Moloch Gibbons, like Kloss’s Gibbons (H. klossii), do not duet, but more detailed studies are needed to confirm this. Median densities are 2-7 groups/km? or 9 ind/km? in lowland forest (below 500 m above sea level), 2:6 groups/km?* or 8:6 ind/km? in hill forest (500— 1000 m), and 0-6 groups/km? or 1-5 ind/km? in low montane forest (1000-1750 m).
Status and Conservation. CITES Appendix I. Classified as Endangered on The IUCN Red List. Moloch Gibbons live on one of the world’s most densely populated islands, and they have been severely affected by loss of habitat. Despite protection by law since 1924, numbers of Moloch Gibbons have continued to slide to perilously low levels. Historical deforestation that affected Java in colonial times still maintains an overriding presence on the landscape, effectively restricting the arboreal Moloch Gibbon to continuous tracts of forest around mountain and volcano tops. Habitat disturbance today is relatively low, and populations, while isolated, appear to have stabilized. Wildlife trade exerts an as yet unknown effect on the Moloch Gibbon. It occurs in more than 15 locations, of which nine are protected: Gunung Gede Pangrango, Gunung Halimun, and Ujung Kulon national parks, Gunung Papandayan, Gunung Kedeng, and Gunung Slamet protection forests, and Gunung Tilu, Gunung Simpang, and Telaga Warna protected areas. These gibbons are also found in the Situ Gunung Tourist Park, which offers some degree of protection. The second largest population in the Dieng Mountains is unprotected. More than 95% of the Moloch Gibbons are in populations of more than 100 individuals, and the four largest areas support more than 500 each. In 2002, the wild population was estimated at 4000-4500, and in 2008 at less than 2500 mature individuals.
Bibliography. Andayani, Brockelman et al. (2008), Andayani, Morales et al. (2001), Asquith (1995), Asquith et al. (1995), Brockelman et al. (1998), Chivers (2001), Dallmann & Geissmann (2001a, 2001b), Gates (1992, 1996, 1998, 2002), Geissmann (1991a, 1993), Geissmann & Nijman (1999, 2006), Geissmann, Bohlen-Eyring & Heuck (2005), Geissmann, Dallmann & Pastorini (2002), Groves (2001), Indrawan et al. (1995/1996), Kappeler (1981, 1984), Leighton (1987), Nijman (1995, 2004a, 2004b, 2006), Nijman & Sézer (1995), Rinaldi (1999), Supriatna (2006), Supriatna et al. (2010).
description: Published as part of Russell A. Mittermeier, Anthony B. Rylands & Don E. Wilson, 2013, Hylobatidae, pp. 778-791 in Handbook of the Mammals of the World – Volume 3 Primates, Barcelona :Lynx Edicions on page 783, DOI: 10.5281/zenodo.6727957