Government policies encouraging immigration and timber exploitation, and a lack of presence by state authorities at ground level, have been the main underlying threats, rather than increasing pressure on resources from local communities, it found.
The study, led by Dr Helen Newing of the University of Kent, examined the Peruvian reserves a prominent example of collaborative management which was profiled at the 2003 World Parks Congress. It dismisses claims that such approaches to conservation 'haven't worked'.
Over the past 25 years, says the report, biodiversity conservation has moved from a 'fences and fines' approach based on a system of heavily guarded, protected areas, to a more inclusive way of doing things, in which local communities are invited to take part in management.
Communities are on the ground, and can therefore more easily control access to a nearby protected area. Often, too, they have legal and moral rights based on ancestral use of the area.
But, the study points out, there is now a backlash amongst conservationists against this approach on the basis that such schemes have failed and cannot work in the long term because local populations will always grow and pressure on natural resources will increase indefinitely.
Those taking this view argue that only strict protection and exclusion of local people can prevent further environmental damage.
Local groups, however, counter that community conservation has not been given a fair trial, because governments almost never devolve enough power or give sufficient legal backing to let indigenous groups take control.
Research included an in-depth study of the Tamshiyacu Tahuayo communal reserve in the Amazon region, and a broader review of other such schemes in Peru.
Contact: Becky Gammon
Economic & Social Research Council