Toxic algal blooms - - Winter school on recent advances in diagnosis and management of diseases in mariculture, 7th to 27th November 2002, Course Manual

Abstract

Incidents of phytoplankton blooms, either harmful or harmless, discolouration of coastal waters, either red, pink, brown and green, has been a regular feature along the Indian coasts, especially in the west coast of India. The red tide or red water phenomena are generally intermingled with changes in chemical properties of coastal waters. Introduction of nutrients during the summer monsoon period through river run off and coastal upwelling are major factors influencing the algal blooms. Most cases of blooms have been harmless, since the aquatic fauna will try to avoid the area and fall in fish catches have been reported every time. However, in recent years, a few cases of fish mortality have been reported in the West Coast, due to algal blooms and effects of PSP and DSP depending on the organisms bloomed. Thus the problem of harmful algal blooms along the Indian coast is more serious than apparent and needs urgent attention to check further escalation due to eutrophication.