In an eco-friendly move to clear aquatic weeds, the Ernakulam Krishi Vigyan Kendra(KVK) released juveniles of grass carp, a freshwater fish that eats aquatic plants, into Kadupadam Chira, Mookkannur in Angamaly in Ernakulam district.

Excessive growth of aquatic weeds causes choking of water resources and is posing threat to the freshwater ecosystem, leaving many of the ponds on the verge of deterioration. The menace is mostly seen in stagnant water resources, said Shinoj Subramannian, Head of the KVK.

A joint mission to rejuvenate the waterbody with the support of Kadupadam Chira Samrakshana Samithi and Matsya Club, the fish-ranching was part of the Centre’s Swachh Bharat campaign.

Grass carp (Ctenopharyngodon idella) had been successfully used in the past too by the KVK to tackle the weed menace in the district. The KVK, functioning under the CMFRI, stepped in to grow these fish in ponds as the water bodies continue to be fast-infested with weeds even after repeated manual clearing.

According to the KVK, as many as 20 grass carps are enough to clear a one-acre-sized water resource infested with weeds. The fish consumes aquatic plants up to two or three times its total body weight on an average. Since it does not breed, there is no chance for the proliferation of the fish in the pond. Though there are around 140 varieties of aquatic weeds available, species such as salvinia, hydrilla and pistia are the most abundant and harmful in freshwater resources. Growing grass carp is an eco-friendly solution to clear out the weeds instead of using chemical compounds which are expensive and harmful to fishes and the aquatic ecosystem, he said.

Published on November 2, 2022