Despite the fishing ban introduced during the fish spawning season to sustain aquatic species for over a decade long, fishing resources in the Zhoushan Fishery in the sea area are unable to support the livelihood of 210,000 local fishermen, according to the fishery authorities in east China's Zhejiang Province.

    Eighty-one percent of the sea area has been rated category four for pollution, the second worst of five pollution grades, in a survey by the Zhejiang Provincial Environmental Bureau. The polluted area has expanded from 53 percent rated category four in 2000.

    Known in China as the Zhoushan Fishery, the East China Sea area was listed among the world's largest in the last century with its 20,800 square kilometers providing a tenth of China's total catch in 2002.

    The Zhoushan Fishery Bureau said on Tuesday that the annual catch dropped from over 1.3 million tons in 2001 to 980,000 tons last year, and the quality of the fish species that were caught had degraded.

    Meanwhile, the number of people employed in the Zhoushan fishing industry has fallen from a high of 250,000 to an estimated210,000.

    Former fishermen Yu Zhaozhang decided to abandon his 30-year fishing career in 2003.

    "There were fewer and fewer cash fish and more juvenile fish in each haul. I realized that the lack of fish would soon put a lot of fishermen out of business," said Yu, who now owns a sea-food restaurant.

    Due to squabbles over the resources in the East China Sea between China, Japan and the Republic of Korea, Chinese fishermen traditionally making a living through deep-sea fishing have returned to inshore sea areas to avoid confrontations.

    This has aggravated overfishing in the Zhoushan Fishery and over 90 percent of deep-sea fishing operations in Zhejiang Province have been affected, resulting in a reduction of 450,000 tons in annual sea fish output.

    Pollutant samples show petrochemical waste and heavy metal sediments are the main contaminants.

    However, the sea area has been explored as one of China's major offshore oil-bearing sea grounds along with Bohai Sea, Yellow Sea and the northern continental shelf of South China Sea, where China's offshore oil prospecting mainly concentrates.

    The government of Zhoushan, the island city from which the fishery gets its name, has provided funding and training to help fishermen retrain in a new profession, such as aquaculture, sea-food processing and marine tourism, but the dwindling fishery is still trawled by thousands of vessels.

    The ocean environmental survey, carried out by east China's Zhejiang Province, which administers the fishery, has also shown the actual fishing area has nearly halved due to restrictions on fishing around the burgeoning number of undersea pipelines and cables.

    Chinese law forbids fishing within two kilometers of fiber-optic lines, oil pipelines and electricity lines in the Zhoushan Fishery, resulting in 8,000 square kilometers of the area rendered technically out of bounds.

    Marine environmental monitoring has shown that half of China's "red tides" caused by pollution now appear in the Zhoushan Fishery.

    Ma Chaode, a water expert with the environmental group WWF China, said pollution was making the Zhoushan Fishery unsustainable and destroying fish stocks in one of the world's major sea fisheries. Enditem