The yummy fish delicacy on your plate is contributing significantly to global warming and climate change.
Fisheries scientists of Central Institute of Fisheries Technology, Kochi, have estimated that fishery activities taking place on the Kerala coast adds 8.07 lakh tonnes of carbon dioxide to the atmosphere each year. Annually around 6.7 lakh tonnes of fish are caught and brought to the Kerala coast by the fleet of both mechanised and motorised fishing vessels.
One tonne of oil sardine, one of the most sought after fish variety in Kerala, when fished and brought to shore in a kerosene-fueled motorised vessel, would release 402 kg of carbon dioxide into the atmosphere. Carbon emissions would be lower for a mechanised vessel which uses diesel engine for the catch. It has been estimated that such a vessel would release 300 kg of carbon dioxide for every tone of sardine landed.
While a motorised Ring Seine unit would use 150 liters of kerosene for production of one tone of oil sardine landing, the fuel consumption would be 112 liters per ton of fish landed in a mechanised vessel. The fuel consumption would go up significantly when trawl nets are used.
While carrying out the assessment of the carbon footprint of the fisheries sector of the State, the scientists didn’t restrict themselves to the use of fossil fuel in the fishing vessels. They approached the issue in a holistic manner and adopted Life Cycle Assessment (LCA) to quantify the scale and importance of emissions with the mechanised and motorised vessels.
Nearly 50 per cent of total fish that lands in Kerala coast are netted using Ring Seine. When it comes to sardine, over 90 per cent is caught using the ring seine, according to C.N. Ravisankar, director of the Institute.
The motorized fleets left higher environmental impacts due to the operational issues like the intensive use of kerosene as fuel by inefficient outboard engines. However, mechanised ring seiners with inboard vessels, which were fired by diesel, went relatively soft on environment.
The assessment was carried out as part of a research project, green fishing systems for tropical seas, which was supported by the National Agricultural Science Fund.
Leela Edwin, the Head of the Fishing Technology Division of the Institute, was the principal investigator of the project and Dhiju Das, a researcher of the Institute was also part of the project.
During the assessment, 10 environmental impact categories, namely abiotic depletion, acidification potential and eutrophication, global warming, human toxicity, marine aquatic eco-toxicity and stratospheric ozone depletion potentials were evaluated. The photo-oxidant formation potential and terrestrial eco-toxicity potential of the fishery were also chosen to quantify the environmental impacts associated with the activities.