Dolphins are spotted in the sea near the wharf of Haimen Port New Area on June 5 in Haimen district, Nantong. [Photo/WeChat account: haimenfabu]

Over 50 dolphins were seen splashing about in the sea near the wharf of Haimen Port New Area on June 5 in Haimen district, Nantong, East China's Jiangsu province, according to local media reports.

This group of dolphins was discovered by Zhang Yong, an employee of Nantong Dongzao Port Development Co Ltd, while he was out on a patrol. "This is the first time I've seen this in my 10 years of working here", said Zhang.

Dolphins are classified as a second-class national protected animal. According to professionals from the Nantong Environmental Testing Center of Jiangsu Province, this kind of dolphin mainly lives in the Bohai Sea, the Yellow Sea and the East China Sea.

Dolphins are very particular about water quality and environment, making their presence a good indicator of the health of a marine ecological environment. Their appearance shows that the district's fishing moratorium and the conservation of fishery resources have had a significant positive effect.