From Sandeep Sharma
GUWAHATI: Environmental degradation leading to depletion of dissolved oxygen level has claimed the lives of hundreds of fish in the historic Dighalipukhuri pond in the capital city Guwahati, state fisheries minister Parimal Suklabaidya said on Sunday.
Preliminary investigation has ruled out poisoning and environmental degradation is suspected to be the cause, he said.
As many as 400 fish species (Rohu, Carla, Mrigal, Silver Carp, Common Carp and Tilapia (1 to 5 kg) weighing around 600 kg have been found dead in the pond since Saturday night following which the minister had directed officials of his department to visit the site and ascertain the exact reason.
After examination of samples of the dead fish and the Dighalipukhuri, the officials found that depletion of dissolved oxygen in the waterbody coupled with high organic load were the causes behind the mass fish deaths.
“Fish mortality was due to sudden dip in oxygen level and high organic load in the tank. Departmental officers after examination found that the deaths were not due to poisoning, but because of environmental degradation,” Suklabaidya said.
As a short-term measure, the oxygen level of water has been increased by showering water through pumps and boating, he added.
The dead fish were retrieved since morning and buried at a nearby spot.
The Dighalipukhuri, more than 500 metres long, is located in the Ambari area of the city.
The origin of this dug-out pond is not clear, with some accounts claiming that it dates from the Mahabharata era, while others maintain that it was dug by Ahom rulers.
It was originally connected to the Brahmaputra, which flows along the length of Guwahati, and had served as a naval yard during the Ahom rule.
The canal was later filled up during British rule. Dighalipukhuri, which has boating facilities, is a popular tourist spot in the city.