The red tides occurrence in Bohai and Yellow Seas was on the rise last year, according to the latest information provided by China North Sea Office of State Oceanic Administration.

The statistics indicated that in 2004, a total of 25 red tides had occurred in Bohai and Yellow Seas, affecting an area of 7340 km2, with two toxic red tides found in Bohai Sea. Compared with 2003, the red tides increased significantly in terms of frequency and area in 2004.

In 2004, the red tide of Yellow Sea firstly appeared in late March and reached its climax in August and September. 13 red tides occurred through the year, with an increase of 1.5 times. A total area of 820 km2 were affected, doubling that in 2003.

In Bohai Sea, the red tides occurrence was almost the same as that in 2003, with the first toxic red tide in June 2004. However, the affected areas increased by 13 times.

To address this issue, the nation has invested enormous funding in strengthening red tides monitoring since early 2004. So far, 33 monitoring sites on red tides have been located in nearshores, with an identification rate of 100%.