Kochi, Nov 23 (IANS): Despite significant advances in meteorological field, hundreds of fishermen in Kerala still have a thing or two to tell scientists. They rely on their traditional wisdom on weather and sea currents handed down the generations to ensure a good catch of fish from sea.

Fishermen in the state total around 10.02 lakh, contributing about nine percent to the gross state domestic product. Kerala is at the second spot after Gujarat in marine fish production in the country.

Fisherman K. Sreekanth of Vallarpadam near here said those catching fish the traditional way could predict rain by watching the shape and colour of the clouds and wind direction.

"Chances of rain are high in case of 'dhennikkattu', a wind blowing from south-east to north-west direction. There will be no rain despite presence of clouds if the wind blows from north to south," he said.

According to him, timing was more important in getting a good catch.

"Thakkam, the 12 days after 'Ekadashi', is a crucial period during which fishermen usually operate a stake net (commonly called oonnivala) to get a good catch," Sreekanth said.

Fishermen even rely on the colour of the sea to estimate the availability of fish. "A reddish hue in the horizon during certain evenings indicates availability fish like mackerel," the fisherman said.

"Red-water phenomenon covering wide areas and drifting along the currents due to intensive multiplication of certain micro algae is a precursor to fishkill. We avoid fishing in such areas," Sreekanth said.

Another fisherman, V.T. Sebastian, said practical knowledge helped them decide the time to use their fishing equipment for a bumper yield of fish.

"Ashtami, that falls in the middle of two full moons (vavu), is the ideal time for good yield of snappers and groupers," he said.

Both fishermen were part of an eight-member group who made a presentation before the faculty and students of Kerala University of Fisheries and Ocean Studies here on Saturday, celebrated as World Fisheries Day.