Plenty more fish in the sea

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The trawling ban introduced in the waters off the state’s coast in 1988, raised a number of socio- economic issues at the time, but years down the line it appears to have succeeded in what it set out to do.

Not only are scientists happy with the outcome, but also fishermen. The 45-day ban this season started on June 14 and is nearing its end.

Marine scientist N.G.K. Pillai who was part of the team constituted by the state government to study the impact of the trawling ban confirms that it has had a positive effect on both fish wealth and marine ecology.

“We analysed pre-ban and post-ban data going back to the Fifties and found there has been a consistent increase in fish resources,” he says.

For fishermen this has translated into a sustained increase in catch. While in the past they saw 10-year cycles dominated by some pelagic variety like sardines suddenly giving way to domination by mackerels or other varieties, now they go home with a good catch of a variety of fish and prawns.

The waters along the state’s coast usually support a catch of around 5 lakh tonnes during the ban period as conservation methods help provide adequate food for all varieties and also give them sufficient space to grow, explains a senior scientist with the Central Institute of Fisheries Technology.

This is also the spawning period for a variety of fish, though a section of scientists say the monsoon has little to do with this for some varieties.

While banning trawlers from venturing out to sea, coastal states like Kerala and Karnataka, which are allowed to regulate fishing in their territorial waters up to 12 nautical mile, allow traditional fishermen with boats with low-power outboard motors or encircling nets to fish during this time, confident that it will have no detrimental effect.

The ban on trawlers is, however, necessary because they venture deep into the sea and use bag-shaped nets that drag along the sea bottom, gathering all kinds of fish, including the young ones, and tonnes of marine organisms. In the process they can also damage the seabed, say fisherfolk.

Scientists of CIFT and the Central Marine Fisheries Research Institute (CMFRI) estimate that 40 per cent of the catch of trawlers is juvenile and is often discarded.

Fishermen therefore agree that without the ban the marine wealth could be in jeopardy and they would not be able to look forward to the present catch available to them today.

Deficit rainfall becomes threat to marine wealth

Monsoon is generally seen as the spawning period for fish and the ban helps sustain this wealth. But, the issue at stake this time is deficit rainfall, which can mar marine wealth in the days ahead.

The rivers that flow into the sea bring with them rich nutrients that make the sea and ocean a kitchen of delicious food for fish as the gushing waters throw these nutrients to the top.

This spawning season, according to marine scientists, is the period when fish population swells. Though scientists admit that spawning among certain varieties happens over the year, it is prominent during this season when fish migrate to areas where plenty of nutrients are available, moving closer to estuary areas, spawn, and later migrate northwards.

This time, things may prove otherwise, admit scientists. Dr N.G.K. Pillai says that there will definitely be a negative impact. It’s not just the lesser flow of nutrients into the water, but it is also the upset in the spawning of fish.

One noticeable factor this time has been the lack of extensive mudbanks (chakara) where fish breed and grow in large numbers.

There was one such mudbank at Purakkad this time. But the number of fish was not huge as it used to be earlier. Also, there have been no reports of more mudbanks that are a regular feature during monsoons.

Scientist K. Dinesh at CMFRI says that the impact of the weak monsoon will be felt later. Extensive survey and studies would have to be undertaken to estimate the damage that this dry spell has caused to marine wealth.