Doomed journey

Print edition : December 14, 2012

Indiscriminate hunting of migrating freshwater fish makes the Kerala State Biodiversity Board seek a total ban on floodplain fishing during the monsoon.

in Thiruvananthapuram

Fishing in the Vembanad lake in Ernakulam district.-H. VIBHU

ONE of the natural worlds most fascinating sights is the unique formation of mud banks on the Kerala coast during the south-west monsoon season.

During the rains, tranquil areas of highly turbid water are formed along the shoreline and a variety of fish and prawns gather there seeking food and shelter from the adjoining rough sea.

These nutrient-rich mud banks, known as chakara in the local language, are a sign of bounty both to the foraging marine creatures that come there in large numbers as well as to local fishermen who eagerly wait for their arrival, in order to haul up a good catch.

A somewhat similar phenomenon occurs inland every monsoon, in the floodplains of rivers, which include their feeder streams, canals, lakes and other waterbodies, and also in vast stretches of paddy fields. Monsoon floodplain fishery, as it is described, is not that well documented, but is now a cause for concern for conservation scientists.

On the initial days of the south-west monsoon, a large variety of freshwater fish regularly migrate en masse, swimming against the flow in rivers, and even jumping over small obstacles, onto a network of streams and irrigation canals in order to enter the flooded fields and plains, mainly to breed.

The females of most such species carry eggs ripe for laying as they undertake this journey to the lowland plains. There they become sluggish, move with their pairs and lay eggs in nutrient-rich niches in rice fields and other such areas, which remain waterlogged for a while during the rains.

Such monsoon-triggered mass movement of fish is known by crude local names, such as ootha or oothayilakkom, and has traditionally been a cause for celebration among inland fishermen, who survive on commercial exploitation of popular varieties of freshwater fish. Oothayilakkom is to freshwater fishermen what chakara is to their coastal counterparts.

The monsoon flood cycle and the seasonal inundation of floodplains of rivers are critical factors determining the survival of many species of freshwater fish. The nutrients, including rotting vegetation and animal excreta, which accumulate in the floodplains during the dry months, mix with silt brought down by the rivers, and provide the essential conditions for spawning, foraging and growth of many varieties of fish.

Survival under threat

Nevertheless, the fish ought to reach these flooded plains every season without fail if they are to reproduce and ensure survival of their species. But the monsoon journey of many species of fish to the flooded plains of Keralaand their very survivalis increasingly coming under threat.

Destruction of migratory passages, building of sidewalls and check dams, large-scale conversion of paddy fields, extensive use of pesticides in cultivation, sand mining in rivers, and invasion and choking of waterways by alien plant species have all prevented migration of freshwater fish to the floodplains.

However, the most serious danger that these fish encounter is the callousness with which they are trapped, hunted down or killed for profits or for fun by local bands of recreational fishermen, says a study on monsoon floodplain fishery, undertaken last year by the Kerala State Biodiversity Board (KSBB) in five districts of the State. It was the first serious study on the phenomenon.

In many districts of Kerala, the muddying of streams and canals that flow into rivers following the first few spells of rain itself is a sign of the impending fish bounty. Nowadays, once the monsoon begins, river fish swim frantically against the current not into the flooded plains (which only a few eventually reach), but right into a variety of traps, cages and nets, set at several ingenious locations along their path.

A FISH WITH MATURE EGGS caught during its seasonal journey to the floodplains.-COURTESY: KSBB

Others are caught by hand, hacked and killed, or wounded and discarded along with a huge volume of bycatch such as frogs, turtles, crabs and a wide variety of snakes. Holiday fish hunters, among them many non-resident Indians employed in West Asia, are aplenty, and some of them also carry air guns to shoot down the birds that feed on fish. Fish carrying eggs are much in demand, and fetch high prices.

Dr K.P. Laladhas, KSBB Member Secretary, told Frontline that the extensive conversion and fragmentation of paddy fields and streams and canals, sand mining in rivers, and construction of roads and bunds have led to the disappearance of the breeding areas and migratory routes of river fish. But the most potent danger is from the fish hunters, who eagerly await the arrival of the fish along the existing narrow, flooded pathways with nets, knives, lights, traps, cages, baskets, mono-filamentous gill nets and electrocuting gearan inventive range of highly destructive, non-ecofriendly hunting equipment.

According to the study, people often join hands and invest a fortune in setting up elaborate traps made of bamboo and arecanut poles in what has now become a sort of killing fields, where even unwanted, inedible fish and other creatures are massacred. And at any key location, for example, at the mouth of ever-narrowing streams and canals where migrating fish hustle and bustle, there would be around 30 to 50 hunters with traps, and nets and so on to ensure that not one gets past their watch. Suppose a hundred migrating fish enter a stream or a canal from a river, only one or two of them would finally reach the breeding grounds in the floodplains, the study points out.

The result is the mass killing of all fish that come to breed. Their inability to reach traditional spawning areas has already led to a drastic fall in the numbers of many species of freshwater fish in Kerala, Laladhas said.

Dr Oommen V. Oommen, KSBB Chairman, said that the KSBB had, among other measures, recommended to the State government that a total ban on floodplain fishing be imposed during the monsoon.

The study has also recommended a ban on the use of some destructive fishing gear, and initiation of an awareness campaign about unsustainable fishing, depletion of fish stocks and the danger it poses to the survival of several fish species, and steps to protect migration routes.

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