https://www.cas.cn/cm/202505/t20250514_5068206.shtml
https://doi.org/10.1016/j.cub.2025.02.052
https://www.cas.cn/syky/202505/t20250512_5067936.shtml
The Yangtze River basin is densely crisscrossed with water networks and represents an important transportation route in China. Boats have been used on this river since ancient times. Throughout China’s long and well-documented history, poems often depict the native Yangtze dolphin, which leaps from the water to hunt fish.
Researchers at the CAS Institute of Hydrobiology analyzed ancient Chinese poems over the past 1,400 years which contained words on theYangtze finless porpoises and determined their distribution over specific historical periods and geographical locations. Among 724 ancient poems featuring Yangtze finless porpoises, they found
- 477 poems from the Qing Dynasty (1636–1912 AD),
- 177 poems from the Ming Dynasty (1368–1644 AD),
- 27 poems from the Yuan Dynasty (1271–1368 AD),
- 38 poems from the Song Dynasty (960–1279 AD), and
- 5 poems from the Tang Dynasty (618–907 AD).
326 of these poems contained specific geographical locations related to the occurrence of Yangtze finless porpoises in the main stream of the Yangtze River and its tributaries. Using a spatial analysis of 1,056 30×30 km grids and historical data, the researchers were able to capture the complexity of spatial changes in the Yangtze Riverbed, human activities, and landforms over millennia.
The results show that the number of grids in which Yangtze finless porpoises were recorded decreased from 169 in the Tang Dynasty to 59 in the modern period. The total distribution area decreased by 65%. As expected, the most significant decline occurred from the Qing Dynasty (142 grids) to the modern period (59 grids).
“Porpoises come in to rest, the wind is silver and the moon is clear; dragons come out to listen, and black clouds rise” 豚入息风银月澄，龙出听讲黑云起
(Emperor Emperor Qianlong, Qing Dynasty, 1765 on his boat moored in Jiaoshan)
The minimum possible distribution range of the Yangtze River Basin in different dynasties
