Kanjirakode karimeen, with its rich and rare texture, is said to be the most delectable variety of pearl spot. Harvested from the Kanjirakode creek of Ashtamudi, it’s in a different league compared to the regular or farmed kinds.
But the fishers are now finding it hard to net a good catch as both the piscean population and size have collapsed over the years. “We used to get fairly large ones, not the palm-sized fish like this. It’s usually served as whole due to the solid size, but not anymore,” says Joykutty, fisher, pointing to his catch.
The story is no different for many inland fishers who depend on Ashtamudi and Vembanad for their livelihood, especially after Charru mussel, an invasive bivalve species, started colonising the creeks.
The change in the estuarine ecosystem has been posing a serious threat to pearl spot habitats, resulting in an ever-dwindling yield. While studies show a decline in the mean size of the commercially valuable fish, cage farming units and fish sanctuaries set up by Fisheries department are also affected.
Though pearl spot is a species that guards hatchlings and exhibits parental care, it cannot protect the eggs from the bivalve with thick shells.
“Since the bivalve feeds on eggs and hatchlings, there will be a natural decline in population. We have been observing this for a while,” says K. Suhair, Deputy Director, Fisheries Department.
Farmers engaged in cage culture are also struggling as they are unable to control mussel fouling. “Mussels keep covering the cages and it requires a lot of extra effort to clean the units. The shrinking size and low yield are causing us a lot of difficulties in marketing the fish,” says Basil, fish farmer. Charru mussel is also impacting the endemic clam stock by leaving no space for the larvae to settle, affecting the livelihood of fishers engaged in molluscan fisheries in Ashtamudi and Vemband.
Ashtamudi Fish Count 2022. jointly conducted the Department of Fisheries, Ashoka Trust for Research in Ecology and the Environment (ATREE) and Department of Aquatic Biology and Fisheries, University of Kerala, during last month had recorded a widespread invasion of the mussel and a decline in the mean size of pearl spot.
“This is a huge challenge as it can have long-term implications. The situation is serious and we have requested the authorities to conduct a detailed study so that we can look for options to salvage the situation,” adds Mr. Suhair.