Global Invasive Species Database 100 of the worst Donations home
Standard Search Standard Search Taxonomic Search   Index Search

   Macaca fascicularis (mammal)    
Ecology Distribution Management
and Links

         General Impact

    Crab-eating macaques (Macaca fascicularis) may negatively impact biodiversity by eating the eggs and chicks of endangered forest birds. They compete with native birds for resources such as native fruits. They may aggravate the negative effects of exotic plant species by consuming their fruits and aiding dispersal of their seeds. Macaques feed on sugar cane and other crops, affecting agriculture and livelihoods, and can be aggressive towards humans. Macaques may carry potentially fatal human diseases, including B-virus.

         Location Specific Impacts:
    Hong Kong English 
    Human nuisance: Crab-eating macaques (Macaca fascicularis) are disturbing visitors to local parks in Hong Kong, such as Kam Shan, Lion Rock, Shing Mun Country Parks and Tai Po Kau Nature Reserve.

    Hybridisation: Crab-eating macaques (Macaca fascicularis) may hybridise with M. mulatta in Hong Kong.
    Papua (Irian Jaya) (Indonesia) English 
    Agricultural: Crab-eating macaques (Macaca fascicularis) raid crops in Papua – cassava, maize, beans, peanut, papaya, banana, sweet potato, mango, young coconut, pineapple, breadfruit and jackfruit. Some of these crops are no longer planted by farmers, due to the significant loss of yield caused by macaques.

    Competition: Possibly as a result of the competitive pressures exerted by crab-eating macaques (Macaca fascicularis) for food resources, many species appear to have lower numbers and diversity in areas inhabited by macaques. These include birds from the families Columbidae (pigeons), Psittacidae (parrots), Paradisaeidae (birds of paradise) and Podarigidae (frogmouths), as well as small reptiles and large mammals (especially Phalangeridae)

    Economic/Livelihoods: The impact on rural economies is significant in the already poor region. For a plot of farmland of less than 100 hectares in size, annual losses of US$3500 can be incurred due to the activity and feeding habits of crab-eating macaques (Macaca fascicularis) .

    Interaction with other invasive species: Crab-eating macaques (Macaca fascicularis) have the potential to aid the spread of alien plant species including Passiflora spp.
    Mauritius English 
    Agricultural: Crab-eating macaques (Macaca fascicularis) dig up and eat new shoots of sugar cane as well as ripe cane. They also cause damage to crops of cabbage, watermelon, maize, potatoes, pumpkins, pepper, tomatoes and pineapples. They cause US$1.5 to 3 million in damage per year.

    Competition: Crab-eating macaques (Macaca fascicularis) consume and damage unripe native fruits thus competing for food with native birds.

    Herbivory: Crab-eating macaques (Macaca fascicularis) destroy the fruit of native plant species.

    Interaction with other invasive species: Crab-eating macaques (Macaca fascicularis) are one of the main dispersers of introduced plants in Mauritius, contributing to degradation of Mauritian ecosystems. Macaques have helped spread the strawberry guava (Psidium cattleianum) and the large fruit production of the guava helps sustain macaque populations. Outside of the guava fruiting season, macaques rely on native plants for food.

    Threat to endangered species: Crab-eating macaques (Macaca fascicularis) is known to prey on the eggs and chicks of endangered forest birds such as the pink pigeon (see Columba mayeri in IUCN Red List of Threatened Species) and Mauritius fody (see Foudia rubra in IUCN Red List of Threatened Species). They may also prey on nesting female birds and may have contributed to the extinction of a large parrot (see Lophopsittacus mauritianus in IUCN Red List of Threatened Species) and scops owl (Scops commersoni).
    Rats and M. fascicularis were found to be the main nest predators of Mauritian fody during the non-breeding and breeding seasons in the Black River Gorges National Park, according to a study which used photographs and field signs for identification purposes. Rats were found to be responsible for 54% of all predation events and macaques for 37% (9% remaining unidentified). During the breeding season predation by macaques increased, with macaque predation accounting for 41% of all predation events and rat predation accounting for 49% (10% remaining unidentified) (Carter and Bright, 2002).
    Angaur Is. (Palau) English 
    Agricultural: Crab-eating macaques (Macaca fascicularis) destroy cultivated crops.

    Interaction with other invasive species: Palau is home to over 106 alien plant species, and it is probable that crab-eating macaques (Macaca fascicularis) help to disperse these.

ISSG Landcare Research NBII IUCN University of Auckland