The waters of the Arabian Sea turning green off Surathkal and Mukka coast since Monday has left fishermen worried as they fear the change in colour could be due to industrial effluents.
A seven-kilometre stretch of the sea, from Kulai till Sasihithlu-Munda, has turned green in colour. A few traditional fishermen said that they have not been able to land a catch following the development, and even as their nets were found to be coated with oily green substance, others said that they were able to catch some fish.
Sudhir, a traditional fisherman from Surathkal, said that they used to witness this phenomenon regularly. It is an annual occurrence, he added.
However, Shobendra Sasihithlu, a traditional fisherman from Sasihithlu, told The Hindu that though the sea waters had turned green earlier too, this year, it was on a higher scale. The colour was dark green and the sea waters contained small floating particles, he said and showed water that he had collected in a glass. He said that the change could be due to high inflow of industrial effluents.
Principal Scientist and Scientist in-charge of Central Marine Fisheries Research Institute (CMFRI), Mangaluru, Prathibha Rohith, said that the occurrence resembles algal bloom. A few days ago, a similar development was reported off Kasargod coast in Kerala too, she said.
Scientists from her institute are collecting water samples from Surathkal and surrounding beaches and only after examining the samples, she could exactly comment about the development, Dr. Rohith said.
She said that besides natural reasons, algal bloom could be a result of industrial effluents that were rich in nitrogen and other components. Algae are rich in nutrients upon which fish feed. If there was a crash after the bloom, the concentration would not be that good for marine fauna, she added.