KARACHI, Nov 5: A number of fish perish every year on the coast of Karachi in October owing to varied reasons.

Dr Javed Mustaquim, a professor of the Marine Biology Department, University of Karachi, said on Monday that it had been observed for the past 10 years that in October a number of small fish died on Sandspits and Clifton beaches but its causes had not yet been determined.

Prof Javed Mustaquim said that one theory was that during the period the excessive growth of some microscopic plants such as phytoplankton that reportedly caused toxicity caused the death of small fish.

He said another theory was that the lack of oxygen in the sea during October resulted in the deaths.

However, Prof Mustaquim stressed that there was a need to determine the precise cause for such a phenomenon and take measures for preventing such an occurrence.—APP