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Providing evidence to improve practice

Action: Create/protect forest patches in highly fragmented landscapes Primate Conservation

Key messages

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  • One before-and-after study in Belize found that black howler monkey numbers increased by 138% over 13 years after the protection of forest along property boundaries and across cleared areas, alongside other interventions.

Supporting evidence from individual studies


A before-and-after trial in 1985-1998 in secondary riparian forest in the Community Baboon Sanctuary, Belize, South America found that a population of black howler monkey Alouatta pigra, for which forest buffer strips along property boundaries and strips of forest across large cleared areas were maintained alongside ten other interventions, increased by 138% over 13 years. The population increased from 840 to more than 2,000 individuals (138%), although no statistical tests were carried out to determine whether this difference was significant. Additional interventions included the protection of the sanctuary by the communities surrounding it, preserving a forest corridor along the river, constructing pole bridges over man-made gaps, preserving important howler food trees in large clearings, involving local communities in the management of the sanctuary, creation of a museum for education purposes, an eco-tourism and research program, presence of permanent staff, and monetary (income from tourism and craft industries) benefits to local communities for sustainably managing their forest and its wildlife communities. The study does not distinguish between the effects of the different interventions mentioned above.

Referenced papers

Please cite as:

Junker, J., Kühl, H.S., Orth, L., Smith, R.K., Petrovan, S.O. & Sutherland, W.J. (2019) Primate conservation. Pages 439-491 in: W.J. Sutherland, L.V. Dicks, N. Ockendon, S.O. Petrovan & R.K. Smith (eds) What Works in Conservation 2019. Open Book Publishers, Cambridge, UK.