Abstract

Two species of cetaceans live in the Yangtze river (Changjiang R.): Lipotes vexillifer (MILLER, 1918) and Neophocaena asiaeorientalis (PILLERI and GIHR, 1972). Both species are only found in the middle and lower Changjiang, i.e. between Yichang and the river mouth. The Three Gorges constitute a
zoogeographical barrier upstream. Neophocaena also occurs in the Dungting Lake, whereas Lipotes has abandoned the lake as a result of increasing sedimentation.
A description is given of the ecology and biotope of the two species. The size and geographical distribution of the now greatly reduced populations is indicated. Attention is drawn to the abiotic factors which threaten the survival of the Yangtze cetaceans. Between Wuhan and Dung Tinghu hook fishing is the main cause of death for Lipotes (up to 50 of deaths). Measures are being discussed to prevent the continued declination of dolphins.