Amazon Rope Bridges Allow Thousands of Safe Wildlife Crossings

New rope bridge installations in Brazil's Amazon have allowed thousands of arboreal animals to cross roads without incident, offering a solution to habitat fragmentation.

New infrastructure in Brazil’s Amazon region has enabled thousands of arboreal animals to cross roads safely, according to a report by Mongabay. Rope bridges installed over highways are providing a way for wildlife to navigate areas where human development has divided their habitat.

In Alta Floresta, located in northern Mato Grosso state, eight bridges were put in place in 2024. Over the subsequent 15 months, camera traps recorded 15,000 crossings by various arboreal species. No roadkill was reported at these monitored sites during this period.

Six primate species have used the structures. These include the black-faced black spider monkey, Schneider’s marmoset, and the critically endangered Alta Floresta titi monkey. The bridges incorporate multiple layers of rope to accommodate different forms of movement, allowing animals to walk, swing, or use their prehensile tails to cross. While some species adapt quickly, cameras show others, like tufted capuchins, took up to seven months to begin using a bridge.

This work builds on an earlier project initiated in 2021 along the BR-174 highway, which runs through the Waimiri-Atroari Indigenous Territory. With assistance from the Waimiri-Atroari community in site selection, 32 bridges were installed. Cameras there have documented about 1,250 primate crossings over the past five years, providing data on effective bridge designs.

Roads pose a significant threat to wildlife by fragmenting habitats, forcing canopy-dwelling animals to the ground, and reducing gene flow between isolated populations. Researchers estimate that nearly 9 million mammals die on Brazilian roads annually. Reduced numbers of fruit-eating primates can also lead to less seed dispersal in nearby forests.

Brazil is moving to address this issue at a policy level. A bill awaiting a Senate vote aims to establish a national wildlife road-safety plan. This plan would include provisions for aerial bridges, underpasses, warning signs, and speed controls. Brazil’s transport infrastructure department has already adopted the Reconecta bridge design as a recommended highway standard. Further bridges are planned for Alta Floresta, other parts of Brazil, and Suriname, though their long-term effectiveness depends on consistent maintenance and monitoring.

For hosts building and operating jungle stays, these projects underscore the importance of designing structures and managing land in ways that support local wildlife movement.