Action

Regularly provide supplementary food to primates during resource scarce periods only

How is the evidence assessed?
  • Effectiveness
    40%
  • Certainty
    10%
  • Harms
    10%

Study locations

Key messages

  • One before-and-after study in the Republic of Congo found that the majority of chimpanzees survived for at least five years after supplementary feeding in resource scarce periods, alongside other interventions.
  • One before-and-after study in Kenya found that wild olive baboons survived for at least 17 years after supplementary feeding in drought periods soon after translocation, alongside other interventions.
  • One controlled study in Madagascar found that the diet of black-and-white ruffed lemurs was similar to that of wild individuals after supplementary feeding in resource scarce periods, alongside other interventions.

About key messages

Key messages provide a descriptive index to studies we have found that test this intervention.

Studies are not directly comparable or of equal value. When making decisions based on this evidence, you should consider factors such as study size, study design, reported metrics and relevance of the study to your situation, rather than simply counting the number of studies that support a particular interpretation.

Supporting evidence from individual studies

  1. A before-and-after trial in 1994-1999 in tropical forest in Conkouati-Douli National Park, Republic of Congo found that the majority of reintroduced chimpanzees Pan troglodytes troglodytes that were supplemented with food during resource-scarce periods along with 16 other interventions, survived for at least five years. Out of 20 reintroduced chimpanzees that were provided with supplementary food, fourteen survived (70%). No statistical tests were carried out to determine whether the population decrease was significant. Individuals were radio-collared and followed at distances of 5-100 m. Rehabilitated orphaned chimpanzees underwent vaccination, treatment for parasites and veterinary screens before being translocated in four subgroups from the sanctuary to the release site with resident wild chimpanzees. Staff members were present to monitor primate health and examine any mortality. The reserve status was upgraded to national park in 1999. Local people were relocated from the release site to a nearby village. Some individuals were treated when sick or injured. TV and radio advertisements were used to raise chimpanzee conservation awareness and local people were provided monetary and non-monetary benefits in exchange for their conservation support. The study does not distinguish between the effects of the different interventions mentioned above.

    Study and other actions tested
  2. A controlled study in 2001 in tropical forest in Betampona Reserve, Madagascar found that captive-bred, reintroduced black-and-white ruffed lemurs Varecia variegata variegata that had limited free-ranging experience before release and that were occasionally provided with supplementary food alongside other interventions, had diets that partly overlapped with that of the resident wild group. Reintroduced lemurs (three males and one female) fed on 54 species during a single year, compared to the wild group (ten individuals) that fed on 109 species over four years. Reintroduced lemurs consumed less foliage than the wild group, although no statistical tests were carried out to determine whether this difference was significant. Supplementary food was provided for three months after release and for four months during the wet/cool season during which time their body mass decreased by 300–500g (10–16%). Lemurs were introduced in groups into habitat already occupied by the species. The study does not distinguish between the effects of the different interventions mentioned above.

    Study and other actions tested
  3. A controlled study in 1997-2001 in tropical forest in Betampona Reserve, Madagascar found that diets of captive-bred, reintroduced black-and-white ruffed lemurs Varecia variegata variegata that were born and raised in a free-ranging environment and provided with food during resource-scarce periods along with other interventions, overlapped with that of the resident wild group. No statistical tests were carried out to determine whether this overlap was significant. Reintroduced lemurs (three males and two females) fed on 92 species over three years, as compared to the wild group (ten individuals) that fed on 109 species over four years. Reintroduced lemurs consumed less foliage throughout the study and less nectar in 1998 than the wild group, although no statistical tests were carried out to determine whether this difference was significant. Two of five reintroduced individuals (both males) died of malnutrition in 1998. Supplementary food provisioning ceased two months after release, but was reinstated for four months following the death of the two males. Lemurs were introduced in groups into habitat already occupied by the species. The study does not distinguish between the effects of the different interventions mentioned above.

    Study and other actions tested
  4. A controlled, before-and-after trial in 1973-2001 in savannah at Chololo ranch, Laikipia Plateau, Kenya found that translocated crop-raiding wild olive baboons Papio anubis that were temporarily provided with food during resource scarce periods along with other interventions, survived over 17 years post-translocation. The size of the translocated population consisting of two troops totalling 94 baboons in 1984, decreased to 62 individuals in 2001 but this decrease was not statistically significant and survival rates did not differ between control and study groups. One wild troop at the capture site and another resident troop at the release site served as control groups. Immediately after translocation and in 1986, baboons were provided with cattle feed, once for three weeks and once for 13 weeks during drought. No supplementary feeding was provided after 1986. Both troops were released into habitat with resident baboons and predators. Prior to translocation of these ‘problem’-animals, individuals underwent veterinary screens and some sick baboons were treated. A long-term research study was launched after translocation. The study does not distinguish between the effects of the different interventions mentioned above.

    Study and other actions tested
Please cite as:

Junker, J., Kühl, H.S., Orth, L., Smith, R.K., Petrovan, S.O. & Sutherland, W.J. (2020) Primate Conservation. Pages 431-482 in: W.J. Sutherland, L.V. Dicks, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2020. Open Book Publishers, Cambridge, UK.

Where has this evidence come from?

List of journals searched by synopsis

All the journals searched for all synopses

Primate Conservation

This Action forms part of the Action Synopsis:

Primate Conservation
Primate Conservation

Primate Conservation - Published 2017

Primate Synopsis

What Works 2021 cover

What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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