Primates: Change the number of feeds per day

How is the evidence assessed?
  • Effectiveness
  • Certainty
  • Harms

Study locations

Key messages

  • Two before-and-after studies in Japan and the USA found that when the number of feeds per day were increased the amount of time spent feeding increased in chimpanzees, but hair eating also increased in baboons.


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 study in 1999 in Japan (Morimura & Ueno 1999) found that when food was given twice a day instead of once a day to a group of chimpanzees Pan troglodytes the amount of time spent feeding increased. On average, feeding time contributed to 7% of the behaviours expressed when one feed was offered per day and 24% when two feeds were offered per day. A group of five chimpanzees was observed for 15 days over five one hour time periods when all food was provided in the afternoon at 15:00 h and when one feed was given between 10:00 h and 11:00 h and a second feed at 15:00 h.    (CJ)

    Study and other actions tested
  2. A before-and-after study in 2012 in the USA (Nevill & Lutz 2015) found that increasing feeds from one to two per day increased hair-eating in baboons Papio hamadryas sp. When one feed was provided, hair eating was seen during 1% of the observations, increasing to 3% with two feeds. Eleven baboons, housed as a social group, were offered their standard feed of 5 kg of monkey diet in the afternoon, which was then split into two, 2 kg feeds, given morning and afternoon. Each monkey was observed over six months and two hours of data were collected on each animal.    (CJ)

    Study and other actions tested
Please cite as:

Jonas, C.S., Timbrell, L.L., Young, F., Petrovan, S.O., Bowkett, A.E. & Smith, R.K. (2020) Management of Captive Animals. Pages 527-553 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

Management of Captive Animals

This Action forms part of the Action Synopsis:

Management of Captive Animals
Management of Captive Animals

Management of Captive Animals - Published 2018

Captive Animal 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.

More about What Works in Conservation

Download free PDF or purchase
The Conservation Evidence Journal

The Conservation Evidence Journal

An online, free to publish in, open-access journal publishing results from research and projects that test the effectiveness of conservation actions.

Read the latest volume: Volume 21

Go to the CE Journal

Discover more on our blog

Our blog contains the latest news and updates from the Conservation Evidence team, the Conservation Evidence Journal, and our global partners in evidence-based conservation.

Who uses Conservation Evidence?

Meet some of the evidence champions

Endangered Landscape ProgrammeRed List Champion - Arc Kent Wildlife Trust The Rufford Foundation Save the Frogs - Ghana Mauritian Wildlife Supporting Conservation Leaders
Sustainability Dashboard National Biodiversity Network Frog Life The international journey of Conservation - Oryx Cool Farm Alliance UNEP AWFA Bat Conservation InternationalPeople trust for endangered species Vincet Wildlife Trust