Reintroduce primates into habitat without predators

Overall effectiveness category Unknown effectiveness (limited evidence)
Number of studies: 1
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How is the evidence assessed?

Effectiveness

50%
Certainty

5%
Harms

0%

Calculating overall effectiveness category

Study locations

Key messages

One study in Tanzania found that a population of reintroduced chimpanzees increased over 16 years following reintroduction into habitat without predators.

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

A study in 1966–1985 on a forested island in Rubondo National Park, Tanzania found that eastern chimpanzees Pan troglodytes schweinfurthii reintroduced into habitat devoid of predators along with other interventions, bred and increased in numbers from 17 to at least 20 individuals over 16 years. No statistical tests were carried out to determine whether this increase was significant. At least two males were shot after attacking game scouts. Two new-born infants were observed in 1968 and in 1985. All of the 17 reintroduced chimpanzees had been born in the wild and had spent time in captivity. Their age at the time of release varied from four to 12 years. Chimpanzees were released in four lots (from 1966 to 1969). Chimpanzees in the first release group were provided with supplementary food for two months. The study does not distinguish between the effects of the different interventions mentioned above.
Study and other actions tested
Referenced paper
Borner M. (1985) The rehabilitated chimpanzees of Rubondo Island. Oryx, 19, 151-154.

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

This Action forms part of the Action Synopsis:

Primate Conservation

Related Actions

Actions	Effectiveness	Studies	Category
Allow primates to adapt to local habitat conditions for some time before introduction to the wild Action Link	Unknown effectiveness (limited evidence)	25	Synopsis Link
Translocate (capture & release) wild primates from development sites to natural habitat elsewhere Action Link	Unknown effectiveness (limited evidence)	6	Synopsis Link
Reintroduce primates into habitat without predators Action Link	Unknown effectiveness (limited evidence)	1	Synopsis Link