Fishing boats head out to sea in Weihai, Shandong province. The four-month fishing moratorium in the Bohai Sea and Yellow Sea ended on Thursday. [Photos by Li Xinjun/For chinadaily.com.cn]

About 17,000 fishing boats set sail from ports in Shandong province on Thursday with high hopes for a good catch, as the recent four-month fishing moratorium in the Bohai Sea and Yellow Sea ended on Thursday.

The summer fishing moratorium is part of China's effort to promote sustainable fishery development and improve the marine ecology.

Fishing boats head out to sea in Weihai, Shandong province. The four-month fishing moratorium in the Bohai Sea and Yellow Sea ended on Thursday. [Photos by Li Xinjun/For chinadaily.com.cn]

Fishing boats head out to sea in Weihai, Shandong province. The four-month fishing moratorium in the Bohai Sea and Yellow Sea ended on Thursday. [Photos by Li Xinjun/For chinadaily.com.cn]

Fishing boats head out to sea in Weihai, Shandong province. The four-month fishing moratorium in the Bohai Sea and Yellow Sea ended on Thursday. [Photos by Li Xinjun/For chinadaily.com.cn]

Fishing boats head out to sea in Weihai, Shandong province. The four-month fishing moratorium in the Bohai Sea and Yellow Sea ended on Thursday. [Photos by Li Xinjun/For chinadaily.com.cn]

Fishing boats sail from a port in Lanshan, Shandong province, after a recent fishing moratorium ended on Thursday. [Photo provided to chinadaily.com.cn]