Heck’s macaque (Macaca hecki)

Synonyms: Macaca tonkeana hecki
GenusMacaca (1)

Classified as Vulnerable (VU) on the IUCN Red List (1) and listed on Appendix II of CITES (2).

Stout-bodied and strong-limbed, Heck’s macaque is one of several closely related macaque species endemic to Sulawesi in Indonesia (3) (4). Heck’s macaque has a varied pelage comprising a black back, a brownish chest and stomach, dark-brown forearms, and pale brownish-grey hind-limbs (5). The tail is relatively short, and the bare, hardened patches of skin on the rump, termed the ischial callosities, are grey to yellow in colour (5) (6). Where ranges overlap, Heck’s macaque is known to occasionally hybridise with the Tonkean macaque (M. tonkeana), and possibly also the Gorontalo macaque (M. nigrescens), with the hybrids sharing external characteristics of both parent species (1) (5) (6) (7).

Heck’s macaque is restricted to the western part of the northern peninsula of Sulawesi, Indonesia (1) (3).

Occupies primary and secondary tropical rainforest (1).

As one of the least studied of the Sulawesi macaques, very little is known about the ecology of Heck’s macaque (1). However, all Sulawesi macaques appear to be diurnal and primarily frugivorous, while also supplementing their diet with leaves, flowers, insects and other small invertebrates (1) (3) (6). Many of the Sulawesi macaque species are also known to commonly raid cultivated crops for fruit, maize and vegetables (1). 

With a burgeoning human population putting increasing pressure on the local environment, habitat loss and fragmentation present the greatest threat to Heck’s macaque. In addition, this species is also directly persecuted by farmers who consider it to be an agricultural pest (1).

In addition to being listed on CITES Appendix II, which prohibits trade in this species without a permit, Heck’s macaque occurs within at least six protected areas across its range (1) (2). In order to tackle wildlife crime in North Sulawesi, a Wildlife Crimes Unit was established in 2001 by the Indonesian Department of Forestry and the Wildlife Conservation Society. The unit has been highly effective at reducing trade in some protected mammals and is working with local communities to strengthen conservation awareness (8) (9).

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  1. IUCN Red List (November, 2009)
  2. CITES (November, 2009)
  3. Nowak, R.M. (1991) Walker's Mammals of the World. The Johns Hopkins University Press, Baltimore and London.
  4. Macdonald, D.W. (2006) The Encyclopedia of Mammals. Oxford University Press, Oxford.
  5. Watanabe, K. and Matsumura, S. (1991) The borderlands and possible hybrids between three species of macaques, M. nigra, M. nigrescens, and M. hecki, in the northern peninsula of Sulawesi. Primates, 32: 365-369.
  6. Bynum, E. L., Bynum, D.Z. and Supriatna, J. (1997) Confirmation and location of the hybrid zone between wild populations of Macaca tonkeana and Macaca hecki in Central Sulawesi, Indonesia. American Journal of Primatology, 43: 181-209.
  7. Bynum, N. (2002) Morphological variation within a macaque hybrid zone. American Journal of Physical Anthropology, 118: 45-49.
  8. Lee, R.J., Gorog, A.J., Dwiyahreni, A., Siwu, S., Riley, J., Alexander, H., Paoli, G.D. and Ramono, W. (2005) Wildlife trade and implications for law enforcement in Indonesia: A case study from North Sulawesi. Biological Conservation, 123: 477-488.
  9. Wildlife Conservation Society (November, 2009)