Corridors in heavily fragmented landscapes: reconnecting populations of critically endangered brown spider monkeys (Ateles hybridus) and sympatric terrestrial vertebrates in the lowland rainforests of Central Colombia

In tropical ecosystems, habitat degradation and fragmentation are some of the most important drivers of biodiversity loss. In Colombia, the Magdalena River basin is home to a megadiverse wildlife community, which has been historically exposed to pervasive habitat loss and fragmentation. Within a long-term project on the conservation of critically endangered brown spider monkeys (Ateles hybridus), we signed conservation agreements with local landowners to protect the remaining forests and reconnect them through restoration corridors. We established 10 corridors within a matrix of pastures used for cattle-ranching which reconnect approximately 1,000 ha of forests. We planted trees in 2016/2017 and 2020, established 24 vegetation plots (10 x 10 m) to measure their structure and composition, and compared them with six vegetation plots (50 x 2 m) in forest fragments. We installed camera traps to evaluate the effectiveness of corridors as potential pathways for terrestrial vertebrates in a fragmented landscape. Overall, forest structure differed between young corridors (1 year) and both older corridors (5 years) and forests; older corridors had no structural differences with forest fragments. Throughout this preliminary survey, 21 out of 32 species of vertebrates that have been recorded in forests used the corridors, including apex predators and other large birds and mammals. This study provides initial data supporting the use of corridors as a strategy to reconnect wildlife in isolated forest fragments in heavily fragmented landscapes, as well as the establishment of effective corridors that reconnect forest-dwelling species in relatively short periods of time (<5 years).

Automated summary

The study found that in the heavily fragmented landscape of the Magdalena River basin in Colombia, corridors can reconnect wildlife in isolated forest fragments, resulting in biodiversity recovery in a relatively short period of time (<5 years).