A massive algae bloom that was first detected on China’s east coast in 2009 has been identified as the world’s largest brown tide, researchers said yesterday.
“The brown tide, similar to the one that has been spotted on the east US coast since 1985, could bring the destruction of fisheries in east China,” said Zhou Mingjiang, a professor with the Institute of Oceanology under the Chinese Academy of Sciences who conducted the research.
Zhou discovered that the yellowish-brown algae are of the same species as those found in the east US coast’s brown tide.
“Thus, it is a more destructive brown tide, rather than the more common red tide,” Zhou said.
The brown tide is the first to hit China, making it the third country to be hit by such tides after the US and South Africa. The brown tide, first spotted off the coast of Hebei Province in June 2009, has restrained the growth of cultivated scallops, oysters and mussels.
The tide expanded between 2010 and 2011, reaching 3,350 square kilometers in July 2010, and is believed to be growing even larger.
“The brown tide broke out again in late May this year and has reached the coast of Shandong Province, which borders Hebei on the south,” said Yu Rencheng, Zhou’s colleague. “This might mean that the brown tide is expanding.”
Brown tides can cause shellfish to stop eating, which eventually leads to their deaths, Zhou said.
“The coastal waters of Hebei and Shandong represent a major aquaculture industry base in China. The brown tide has put the industry at the risk of collapse,” said Yu.
The brown tide caused direct economic losses of 205 million yuan (US$32.2 million) in Hebei in 2010, according to the State Oceanic Administration.
The brown tide might also harm natural fishery resources, as the area is a spawning ground for many species of fish, Zhou said.
Brown algae is fragile and very small, making it difficult to conduct scientific research on the organism, Zhou said.
Zhou said a state-level research program should be launched to control the impact of the tide.
“We should step up international cooperation and obtain references from our US counterparts,” he said.
People’s Daily Online, 2012