Kochi: The massive dumping of chemical waste from industrial and food processing units has resulted in substantial decline in inland fish production in major water bodies like Vembanad lake, affecting livelihood of a large section of fishermen community.
According to marine experts, the annual production of ‘Pearl Spot’ (Karimeen), the most common species, alone has come down from 1,200 to 200 tonnes in the last decade with pollution rampant in sections like Aroor-Thevara stretch of Ernakulam region.
The production of other local fish species including ‘kaara’ (stinging Cat fish), varal (snakehead murrel), ‘chemballi’ (Red Snapper), ‘paral meen’ (crystal fish) and ‘pallathi’ (Orange chromide) too took a beating resulting in their prices spiraling upwards. For instance ‘Pear spot’ now costs `700 per kilo.
“A main reason for decline in fish species is pollution of water-bodies. The use of large-scale illegal fishing practices too contributed to sudden decline of freshwater marine resource. A majority of stake nets and Chinese nets set up in the region are illegal,” said Dr Rajeev Raghavan, Assistant Professor, Fish Taxonomy, Kerala University of Fisheries and Ocean Studies (KUFOS).
“We recently held a study on pollution in the region between Thevara Ferry and Arukutty… There was an increased pollution near Thevara ferry, having close proximity to shipyard and the Harbour. Another polluted station was Nettoor… Here the water was almost stagnant due to macro plastics…One factor we noticed is that the metal concentration of water has increased tremendously,” said Dr Anu Gopinath, Assistant Professor (Chemical Oceanography), Department of Aquatic Environment Management, KUFOS.
Meanwhile, a study by the Thiruvananthapuram-based National Centre for Earth Science Studies revealed that the Vembanad lake is shrinking, both area-wise and depth-wise, affecting marine species.
“40 per cent area of the lake was encroached upon in the last 15 years, while the depth decreased by 65 per cent. As much as 55, 000 ha was reclaimed during the period,” the report said.
