An annual three-month summer fishing ban started on East China's Bohai Sea Tuesday, with experts hopeful of a further revival of the sea's fisheries.

The ban, imposed by the Agriculture Ministry since 1995, is effective from June 1 to Sep. 1.

During that time fishing boats would be prohibited from going to sea, said Zhao Xingwu, director of the oceanic and fisheries department of northeast China's coastal Liaoning Province.

The province was planning to release 230 million larval jellyfish into to sea to help increase fish stocks after the fishing ban, Zhao said.

Other cities and provinces involved are Tianjin Municipality, Hebei Province and Shandong Province.

Illegal fishing will incur penalties, including fines of up to 50,000 yuan (7,300 U.S. dollars), confiscation of the catch, fishing tools and even boats, depending on the seriousness of the violation.

The Bohai Sea, covering 77,000 square km, is almost enclosed by the Shandong and Liaodong peninsulas.

Excessive fishing, over-exploitation and pollution have severely damaged its fishery resources. The output of prawns, an important catch, fell from more than 40,000 tonnes in the 1970s to just 1,000 tonnes in 2004.

With the fishing ban and other control measures in recent years, the total catch increased to 2,000 tonnes in 2009.