Four finless porpoises have been released to the Yangtze River for one month or have been integrated into the natural population.

CCTV News:On May 22nd, the Institute of Aquatic Sciences of Chinese Academy of Sciences released the monitoring progress of four finless porpoises released to the Yangtze River for the first time for nearly one month. These finless porpoises may have been integrated into the natural population.

These four finless porpoises were released to the Yangtze River on April 25th this year, with two ends released to Xinluo section of the Yangtze River in Hubei and two ends released to Swan Island, the stone head of the Yangtze River. This is the first time that China’s ex situ conservation finless porpoises have been released into the Yangtze River, realizing the ex situ conservation of endangered aquatic mammals.

The researchers adopt the radio automatic tracking system, that is, the finless porpoise is dressed with a vest with a radio beacon, and then the finless porpoise is tracked continuously through the acoustic image auxiliary observation system, mobile handheld radio positioning and tracking, visual observation, towed real-time passive acoustics and drones. On April 28th, researchers monitored that two finless porpoises released from the new snail section of the Yangtze River were moving with another wild finless porpoise. However, not long after, the vests of the two finless porpoises fell off, and it was impossible to directly monitor their whereabouts. As a result, researchers conducted further auxiliary monitoring.

Mei Zhigang, Associate Research Fellow, Institute of Aquatic Sciences, Chinese Academy of Sciences:According to the monitoring results, in such a large distribution range, the finless porpoises in the nature reserve are several large groups that move together, not to mention solitary small groups with one head and two ends, and the distribution areas are all in the waters of shoals, estuaries or sandbars, which is almost the same as the distribution of finless porpoises in our previous visits to the nature reserve. Therefore, we speculate that it is very likely that they have integrated into a larger group of protected areas and found suitable habitats.