A railway line cuts through the Hollongapar Gibbon sanctuary. The gibbon census of 2008 recorded 3 families of Hoolock gibbons in the smaller part of the sanctuary and 26 in the larger part. Hoolocks never descend to the ground, preferring to swing from tree to tree in the middle and upper canopy. As you can see from the featured photo, the railway line creates an impassable barrier to these apes.
Hoolock gibbons (Hoolock hoolock) live up to 35 years, have a single baby every two or three years, and mature in 6 years. So, on the average, the number of families doubles in three years. According to an expert who walked us through the forest, there is no overcrowding yet. So the number of families may have tripled in the last 10 years since the census. This means that the population in the smaller section of the sanctuary is in danger of inbreeding.
Recognizing this, the forest department created what they thought was a gibbon bridge. That’s the strange structure which you can see in the photo, crossing the tracks at the level of the upper canopy. We were told that no gibbon has ever used this. When we followed a family of gibbons through the forest we realized that they never walked on branches. For over half an hour we saw them swing and jump from one branch to another. The bridge completely neglects this simple observation. If you know of a bad design award for wildlife conservation, I nominate this bridge.