Dolphins are playing havoc with fishing nets off the coasts of Kollam, Alappuzha and Ernakulam, leaving fishermen, especially the traditional and artisanal ones, a grumpy lot because they are forced to abandon several days of work a week to mend damaged nets.
Fishermen face a double whammy because there is no insurance cover for fishing nets and fishing boats are forced to spend between Rs. 1 lakh and Rs. 10 lakh a year (depending the nets’ sizes) in repairing damaged gear, claimed the president of Kerala Matsya Thozhilali Aikya Vedi (TUCI) Charles George here on Monday.
Fisherman Antony, alias Kuruvi, who is among a score of workers manning the non-mechanised boat Mavelithayyil, said on Sunday that the number of instances in which dolphins damaged nets had increased of late. He, along with co-workers, was on the Chellanam beach on Sunday mending nets damaged on their last expedition.
Non-mechanised boats do not venture far out into the sea. They fish in shallow waters and catch mostly anchovies and other small fishes. The fishermen said that dolphins followed schools of fish into the nets and, once trapped, bit into the nets to escape.
They said they are forced to spend several days a week mending nets as small mesh nets take a long time to repair. Typically, these traditional boats venture out for short durations and return on the same day with their catch, which usually do not sell for more than Rs.10,000. On a good day the fishermen make up to Rs. 600 a day per head.
They said that the number of cases in which dolphins damaged nets had gone up steeply after the trawl ban ended on August 1.
Mr. George said that dolphin attacks had intensified over the past three years possibly because of the increasing population of oil sardines close to the Kerala coast. What had brought about this is not known. It could be the result of climate change, he said, as he pointed out that last year had seen record oil sardine catch off the State’s coast.
N.G.K. Pillai, formerly director of the Central Marine Fisheries Research Institute, said that ravaging dolphins were more frequently being reported over the past one year but the problem was not confined to shallow waters. There have been instances in which even ring seines were damaged in deeper waters, he said.
Dr. Pillai felt that the dolphin population off the Kerala coast may have increased due to successful conservation measures. Mr. George also felt that the dolphin population may have increased in the shallow waters close to the Kerala coast.
It is possible, he said, that a break in the food chain could have caused the dolphins to come closer to the shores. There is a sharp drop in tuna catch over the past three years. This may be one of the reasons why dolphins to look for prey closer to the coast.
He also said that fishermen now used protective layers to prevent dolphins from entering the fishing nets just as turtle extruder devices are deployed by trawlers.
Head of the department of aquatic biology at University of Kerala A. Bijukumar said that the dolphin population had not gone up off the Kerala coast. Instead, he said that the number of trawlers had increased disrupting the feeding habits of dolphins which operated in schools to round off shoals of fish.
Dr. Bijukumar was part of a team of scientists, which studied the practice of artisanal fishermen with cast-nets using Indo-Pacific hump back dolphins in the Ashtamudi estuary to spot shoals of fish. He said that the problem of dolphins causing damage to nets is more frequent in the shallow waters.
Joseph Xavier Kalappurakkal of the Mechainsed Boat Operators’ Association claimed that the number of dolphins off the coast of Kerala increased substantially during the period between August and early October and tended to disappear for the rest of the year.
He felt that dolphins played a positive role because their presence was an indication of the presence of shoals of fish in a particular area.
Mr. George called for insurance cover for fishing nets and also appealed to the State government to evolve a fisheries management system based on studies about the possible break in the maritime food chain.