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Forest fragment is one of the major threats that has resulted in breakdown connectivity in arboreal species. Fragmentation results in high mortality of many species while crossing roads between forest patches. From 2015 to 2017, due to both roadkill and electrocution a total of 27 fatalities were recorded in Satchari and Lawachara National Park of northeast Bangladesh. As an initiative to mitigate this problem, we constructed three single-line artificial canopy bridges in high-risk zones of mortality in Satchari National Park. This reserve forest is fragmented by old Dhaka-Sylhet highway. This highway is the northern limit of the national park and the length of the road inside the forest is 1.76 Km. In addition, an electric power supply line also passes through the forest approaching the highway. The single-line artificial canopy bridges were made of polypropylene ropes and camera traps were used to determine the usage of the bridges by animals. We found a total of 1060 occurrences of artificial canopy bridges using by eight species of mammals over 157 camera trap days. Among the eight mammalian species, five species were primates, two squirrel and one was palm civet. The most frequent bridge user was Irrawaddy squirrel (52%). In the midst of six primate species of Satchari National Park, Phayre's langur most frequently used the bridges (n = 164) followed by capped langur and northern pig-tailed macaque. The only nocturnal primate of Bangladesh Bengal Slow loris was also seen 67 times to cross the bridges. Irrawaddy squirrels and Flying squirrels most frequently used bridge 1. On the other hand, we found northern pig-tailed macaques and capped langurs to use bridge-2 most frequently whereas bridge-3 were most frequently used by Phayre's langurs and Bengal slow lorises. We found a significant difference of number of bridge users between seasons for bridge-1 (χ2 = 47.969, P < 0.001) and bridge-3 (χ2 = 9.013, P < 0.01), but not for bridge-2 (χ2 = 4.72, P = 0.56). During our study period we did not find any mortality of mammals by road accident or electrocution. To avoid mortality from road kill and electrocution we strongly suggest to maintain natural canopy bridges, if not possible build artificial canopy bridges which will increase connectivity between forest patches.Forest fragment is one of the major threats that has resulted in breakdown connectivity in arboreal species. Fragmentation results in high mortality of many species while crossing roads between forest patches. From

Keywords:

Canopy Bridge, Electrocution, Primates, Road kill,

Marjan Maria, Hassan Al-Razi, Ali Akbar, Sabir Muzaffar, KAI Nekaris

Presentation within symposium:

S-34 Reconnecting the forest canopy: Lessons from artificial canopy bridge studies in various geographies and habitats

Bridging Forest Canopies Artificially to Conserve the Arboreal Mammals in a Fragmented Forest Patch of Bangladesh.

-Review-