Improvement of the video camera system mounted on a balloon for supporting the visual census of river dolphins

In order to increase the surfacing dolphin's detection probability by the balloon camera system similar to that of a human observer, improvements were made in the camera system on the balloon [1]. Followed by test on ground, fusion census of both acoustic and visual census with the improved camera system on the balloon was conducted at the same experiment site as 2016 for three days from 6 to 8 February, 2018. The performance of the improved balloon camera system for supporting the fusion census was well demonstrated, even though the balloon census could be conducted only when the wind direction was aligned with the boat cruise direction. The improved system could cover previous system drawbacks and could also capture the individual dolphin's features such as migration behavior of the dolphin with a calf, measurement of body length of the small calf, etc.