The state government is likely to form an expert committee to zero in on the best scientific ways to tackle the invasion of charru mussels (kaaka aazhi), which are spreading inside the ecologically sensitive Pulicat bird sanctuary and Ennore creek like wildfire.
TNIE had travelled extensively across the Pulicat bird sanctuary and Ennore creek recently and found that the invasive species has reached an alarming level extending up to several kilometres. If left unchecked, this will soon turn into an ecological disaster compromising the entire habitat, depleting native life and having ramifications on thousands of migratory birds that visit the region, especially Pulicat. Fishers have already begun complaining of reduction in prawns, crabs and fish life.
The charru mussel is also wiping out the locally prevalent and commercially valuable yellow clams (manja matti) and green mussels (pachai aazhi). A group of fishermen leaders from Pulicat and Ennore along with environmentalists met top government officials including Additional Chief Secretary Supriya Sahu last week. The meeting was facilitated by G Sundarrajan from Poovulagin Nanbargal.
The delegation, in its representation, said the charru mussel invasion has pushed fishermen to the verge of losing their livelihoods. The Tamil Nadu State Wetland Authority visited and initiated a micro-plan in late 2022 for removal of the mussels at Karukkumaram-kandachedi Paadu in consultation with fishers in Ennore followed by measures like bathymetry study, mortality test and prepared a DPR. However, there was no improvement beyond that.
They alleged that the ongoing infestation is aggravated by construction debris dumped within Kosasthalaiyar for various activities including erection of transmission towers. Their demands include establishing a committee by inclusion of fisher representatives to devise a comprehensive plan to remove and control the charru mussels and provide compensation for the loss of livelihoods caused by its colonisation of the Ennore Wetlands.
When contacted, Sahu said the government has taken note of the issue. “Both the environment and fisheries department will work together to expedite the removal of alien mussels from Ennore and Pulicat. An expert committee will shortly be formed which will submit its recommendations,” she said. Fisheries Commissioner Shunchonngam Jatak Chiru said only a holistic and scientific approach will yield results. Some experts recommend dredging and others say it will not work. “We need to talk to different people.
The government has asked for a proposal and am working on it. Experts from CMFRI, NIOT will be consulted.” A few years back, Kerala reported damage due to the spread of this mussel species. The surveys conducted in Kerala found the presence of the mussel in many estuaries/backwaters of Kerala, which include Kadinamkulam, Paravur, Edava-Nadayara, Ashtamudi, Kayamkulam, Vembanad, Chettuva and Ponnani. Ashtamudi Lake, a Ramsar site in Kollam district, is the worst-hit by the charru mussel invasion. Here, it has replaced the Asian green mussel (Perna viridis) and the edible oyster Magallana bilineata (known locally as muringa).