
A highly intense (27,000 cells mL-1) bloom of the nitrogen fixing cyanobacterium Trichodesmium erythraeum was observed in Burmanallah region of Port Blair in South Andaman during summer (March 2012). Hydrographical parameters were studied and nutrients like Nitrate, nitrite, phosphate and silicate were measured. It was found out that an increase in water temperature has initiated the bloom. Increase in salinity was also found to be a factor which had contributed to the bloom.