The northernmost distribution of Indo-Pacific humpback dolphin (Sousa chinensis) in the world: Evidence from preliminary survey in Ningde, China

Northernmost distribution area of Indo-Pacific humpback dolphin or Chinese white dolphin Sousa chinensis in China and world is not certain. From October 2009 to June 2010, we conducted 42 boat surveys and filled in 112 questionnaires. The surveys covered 1756.4km distance in Southeastern China, i.e., Yueqing, Fuzhou and Ningde waters. We sighted the dolphin six times in Ningde that represents the current northernmost distribution area of this species in China and the world. One to two dolphins were recorded in each sighting; four individuals were identified using photographic technology. The encounter rate was 0.47 sightings/100km survey route and 0.79 dolphins/100km survey route. Dolphins' 95% Kernel range and MCP range were 68.1 kM2 and 14.39 km- respectively. These results implied that dolphins inhabiting Ningde waters represented a small community. Considering current various serious threats, it would be difficult for this community to survive for long. Future research prospects have also been put forward.