Amazon canopy bridges log 15,000 animal crossings, zero roadkill in 15 months

Projeto Reconecta, a Brazilian conservation initiative led by biologist Fernanda Abra, installed eight rope canopy bridges in 2024 near Alta Floresta, an Amazon town in Mato Grosso, to reconnect forest fragments split by a highway. Camera traps mounted on the structures documented roughly 15,000 safe crossings by arboreal wildlife over 15 months — including several threatened and critically endangered primates such as Schneider’s marmoset and the Alta Floresta titi monkey — with not a single recorded roadkill in that stretch afterward. The bridges use a low-cost multilayer design that accommodates different locomotion styles, from prehensile-tailed climbers to brachiating spider monkeys, and even ground-dwelling mammals like opossums and sloths.

The conservation payoff goes beyond preventing deaths: restoring connectivity across fragmented habitat enables gene flow and seed dispersal, countering the population isolation and inbreeding that follow when roads carve up forests. Brazil, home to the world’s greatest primate diversity and its fourth-largest road network, loses an estimated 9 million mammals to vehicle collisions annually. Reconecta’s earlier project — 32 bridges built in 2021 with the Waimiri-Atroari people along highway BR-174 — showed that adoption grows over time, with some species taking months to start using a new crossing.

The results carried enough weight that Brazil’s federal transport department has designated the rope-bridge design as its recommended national standard for highways. Abra, a Smithsonian-affiliated researcher, National Geographic Explorer, and Whitley Award winner, is now expanding the approach to additional Brazilian biomes and to neighboring Suriname, with eight more bridges planned for Alta Floresta’s urban area once local power lines are lowered and insulated.