Providing evidence to improve practice

Individual study: First release of captive-bred Mandrills Mandrillus sphinx from the Centre International de Recherches Médicales de Franceville (CIRMF) to Lékédi Park, Bakoumba, Gabon

Published source details

Peignot P., Charpentier M.J.E., Bout N., Bourry O., Massima U., Dosimont O., Terramorsi R. & Wickings E. J. (2008) Learning from the first release project of captive-bred mandrills Mandrillus sphinx in Gabon. Oryx, 42, 122-131


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Remove/treat external/internal parasites to increase reproductive success/survival Primate Conservation

A study in 2002–2006 in closed canopy forest in Lékédi Park, Gabon found that one third of captive-bred reintroduced mandrills Mandrillus sphinx that were treated for parasites alongside other interventions, died within the first year post-release. During this year, mortality was 33% (12/36), with dependent infants being most affected. Fertility rate was 42% (5/12 females gave birth to an infant) and two of the five infants survived for longer than six months. Mortality decreased to 4% in the second year and fertility rate remained at 42%, and all five infants born in the second year survived for at least six months. Mandrill home range remained limited during the first two years after release. In 2006, the group numbered 22 individuals, including 12 of the mandrills originally released, all in good physical condition. All mandrills were treated for gastrointestinal parasites immediately before release. Mandrills were reintroduced as a group into habitat already occupied by the species and predators. They were allowed to adapt to local habitat conditions before release and supplemented with food until 2005. The study does not distinguish between the effects of the different interventions mentioned above.

Provide supplementary food for a certain period of time only Primate Conservation

A study in 2002–2006 in tropical forest in Lékédi Park, Gabon found that one third of captive-bred mandrills Mandrillus sphinx that were provided with supplementary food along with other interventions, died within the first year post-release. Twelve out of 36 mandrills (33%) died within one year post-reintroduction, particularly dependent infants. Fertility rate was 42% (five of 12 females gave birth) and two of the five infants survived longer than six months. Mortality decreased to 4% in the second year and fertility rate remained at 42%, but all five infants born survived for over six months. Their range remained limited during the first two years post-release. In 2006, the group numbered 22 individuals, including 12 translocated mandrills, all in good physical condition. Eight weeks after release, food provisioning commenced daily from non-fixed feeding locations for one month and continued twice weekly until September 2005. The amount of food provided varied with physiological requirements and ecological conditions. Mandrills were dewormed, allowed to adapt to local conditions and reintroduced as a group into habitat with resident mandrills and predators. The study does not distinguish between the effects of the different interventions mentioned above.

Reintroduce primates into habitat with predators Primate Conservation

A study in 2002–2006 in tropical forest in Lékédi Park, Gabon found that around one third of captive-bred mandrills Mandrillus sphinx that were reintroduced into habitat with predators along with other interventions, died within one year. Mortality was 33% (12/36), with dependent infants being most affected. Fertility rate was 42% (5/12 females), where two of the five infants survived for longer than six months. Mortality decreased to 4% in the second year and fertility rate remained at 42%, but all five infants born survived for at least six months. Their range remained limited during the first two years after release. Mandrills were reintroduced as a group into habitat already occupied by the species. Before release mandrills were allowed to adapt to local habitat conditions, and were treated for endoparasites. Mandrills received supplementary feeding until 2005. The study does not distinguish between the effects of the different interventions mentioned above.

Allow primates to adapt to local habitat conditions for some time before introduction to the wild Primate Conservation

A study in 2002–2006 in tropical forest in Lékédi Park, Gabon found that one third of captive-bred mandrills Mandrillus sphinx that were allowed to adapt to local habitat conditions for some time before their reintroduction into the wild along with other interventions, died within the first year after release. During this year, mortality was 33% (12 out of 36 individuals), mostly affecting dependent infants. Fertility rate was 42% (5 of 12 females), where two of the five infants survived over six months. Mortality decreased to 4% in the second year and fertility rate remained at 42%, but all five infants survived for at least six months. Their range remained limited during the first two years after release. In 2006, the group numbered 22 individuals, including 12 of the mandrills originally released, all in good physical condition. To acclimatize, mandrills were placed in a small holding enclosure of 0.5 ha for 2-4 weeks before release. They were reintroduced as a group into habitat already occupied by the species and with predators. They were treated for endoparasites before release and supplemented with food until 2005. The study does not distinguish between the effects of the different interventions mentioned above.

Reintroduce primates into habitat where the species is present Primate Conservation

A study in 2002–2006 in tropical forest in Gabon found that approximately one third of captive-bred mandrills Mandrillus sphinx that were reintroduced into habitat occupied by wild mandrills, along with other interventions, had died one year after release. Mortality was 33% (12/36), with dependent infants being most affected. Fertility rate was 42% (5/12 females), and two of the five infants survived for longer than six months. Mortality decreased to 4% in the second year and fertility rate remained at 42% and all five infants born survived for at least six months. Their range remained limited during the first two years after release. In 2004, a solitary wild male took over the group, after which the group extended its range. Mandrills were reintroduced as a group into habitat with predators, allowed to adapt to local habitat conditions for some time, and treated for endoparasites before release. Supplementary feeding was provided until 2005. The study does not distinguish between the effects of the different interventions mentioned above.

Reintroduce primates in groups Primate Conservation

A study in 2002–2006 in rainforest in Lékédi Park, Gabon found that one third of captive-bred mandrills Mandrillus sphinx that were reintroduced in groups alongside other interventions, died within the first year post-release. Mortality was 33% (12 individuals of 36), mostly affecting infants. Fertility rate was 42% (5 of 12 females reproduced), and two of the five infants survived for longer over six months. Mortality decreased to 4% in the second year and fertility rate remained at 42%, but all five infants survived over six months. Their range remained limited during the first two years post-release. In 2006, the group numbered 22 individuals, including 12 of the mandrills originally released, all in good physical condition. Mandrills were transferred to the release site in two groups and released all together in 2002. Mandrills were reintroduced into habitat already occupied by the species and with predators; they were allowed to adapt to local habitat conditions for some time, and were treated for endoparasites before release. Mandrills were also supplemented with food until 2005. The study does not distinguish between the effects of the different interventions mentioned above.