Indigenous Technical Knowledge (ITK) of coastal fisherfolk on climate change - a case study in Chennai, south-east coast of India

Climate change will have strong impact on fisheries with far-reaching consequences on food and livelihood of a sizeable section of the population. The frequency and intensity of extreme climate events is likely to have a major impact on future marine fisheries production. Fishermen have excellent knowledge on the relationship between climatic, oceanographic factors and fish catch. This knowledge enables them to switch their fishing activities with respect to species exploited, location of fishing grounds and gear used. Based on this backdrop, a survey was conducted to collect primary data on Indigenous Technical Knowledge (ITK) from 200 fishermen in and around Chennai with a structured questionnaire. Fishermen believed that reduction in fish catch in recent years is essentially due to overfishing (Garrett mean score : 82) and juvenile exploitation rather than climate change. Fishermen opined that current (62%) and wind direction/speed (28%) are the major climatic parameters affecting fisheries. Current from south to north direction which generally remains for nine months off Chennai leads to good fish catch, since it is favourable for larval distribution. They believe that combined wind blow from south and west leads to coastal upwelling, which occurs during May-June every year for 45 to 55 days. Current flow from south to north yields more rocky fishes due to turbid water condition and leads to heavy catch. However in recent years fishermen were not able to predict climatic events like in earlier years due to large unexpected seasonal variations. Fishermen suggested that government should bring regulations on craft, gear and related aspects in order to ensure sustainable fishing