yeah it wasn’t the Yangtze, I will edit my comment. I saw it on broadcast and got it wrong. when I searched now I found a CCTV reel from Feb 2:
A pod of Chinese white dolphins was recently spotted swimming and playing in the waters of Sanniang Bay in Qinzhou, south China’s Guangxi Zhuang Autonomous Region. More than a dozen of the graceful animals leapt through the waves, their white silhouettes standing out beautifully against the deep blue sea.
so I guess they were white dolphins and not the Yangtze, sorry
I’ve only seen it used the way QinShiHuangsShlong references