Reconnecting the forest canopy: Lessons from artificial canopy bridge studies in various geographies and habitats


Reconnecting the forest canopy: Lessons from artificial canopy bridge studies in various geographies and habitats

Thu, July 14, 10:30 - 12:30 hrs, Room: Secretaría


Fernanda Abra, Tremaine Gregory, Giselle Narvaez Rivera

Increasing habitat fragmentation caused by linear infrastructure is a major threat to arboreal wildlife across tropical forests. Artificial crossing structures can help mitigate the ecological impacts of fragmentation on wildlife populations and help reconnect the forest canopy. Here we share the lessons learned to scale up ACS implementation.

Projections for global road expansion estimate the construction of 15 million miles of paved roads by 2050, with the vast majority of this growth anticipated to occur in developing countries, including areas of high biodiversity value. As the world becomes increasingly fragmented by roads and other forms of linear infrastructure such as railways, pipelines, and power lines, the importance of maintaining habitat connectivity increases. Although linear infrastructure fragments habitats for all forms of wildlife, it can be particularly obstructive for arboreal species as permanent barriers are formed by these types of infrastructure due to the inability for these species to travel on the ground. Dividing populations of arboreal species can result in decreased access to resources, impacts on dispersal, increased chances of electrocution on power lines, and ultimately, genetic isolation and decreased resilience in a continuously changing world. Artificial crossing structures (ACS), or wildlife bridges, provide a viable solution to maintain habitat connectivity and gene flow between populations divided by linear infrastructure. ACSs can take different forms depending on the target species, including substantial concrete overpasses that facilitate crossing for both terrestrial and arboreal species and simpler suspensory bridges, useable by arboreal species. Being lower cost and easier to construct, the latter have the potential to be implemented on a broader scale, however, they have been used and studied in relatively few locations. Moreover, the limitations of these studies have not allowed for comparisons of the use of different types of structures by species with differing behavior and locomotor patterns. This symposium will bring together researchers studying wildlife use of suspensory ACSs in a variety of contexts, from connecting fragments for the endangered Black lion tamarin in Brazil to reconnecting habitat for primates in Costa Rica and building connections over pipeline right-of-ways in Ecuador. Researchers will describe the challenges presented by the type of linear infrastructure in the study area, the attributes of the ACSs used, and their rate of use by different species. The researchers will also discuss the successes and limitations of their ACS designs, allowing future practitioners to learn from their studies and the development of best practices for different contexts. Lessons learned by all contributing to and attending this symposium will help facilitate efforts to reconnect the forest canopy, building resilience among populations of arboreal species and ultimately contributing to the health and biodiversity of tropical forest ecosystems.

Canopy bridges: A necessary tool towards sustainable infrastructure for arboreal species
Tremaine Gregory*, FERNANDA ABRA, Kylie Soanes, Fernanda Teixeira, KAI Nekaris, Ines Azofeifa Rojas and Birthe (Bibi) Linden

Reconnecting Brazilian rainforests: lessons learned from canopy bridges applied projects
FERNANDA ABRA*, Fernanda Teixeira, Marcelo Gordo, Aline Medeiros, Edson Costa, Patrícia Dias and Márcia M. A. Jardim

Preliminary results on arboreal mammal use of three artificial canopy bridge designs over a logging road in peruvian amazonia.
Vania Tejeda Gómez*, Tremaine Gregory, Farah Carrasco-Rueda and FERNANDA ABRA

Spider monkeys do not use artificial canopy bridges to cross linear infrastructure
Filippo Aureli*, Anja Hutschenreiter, Daniela Araya Gamboa, Esmeralda Arévalo-Huezo, Tamara Avila Atagua, Colline Boiledieu, Alberto González Gallina, Stacy Lindshield, Giselle Narvaez Rivera, Vincent Rufray, Mark Thurber and Denise Spaan