MIRZA, May 27 – In a significant development which may be a serious environmental concern, a huge Gangetic river dolphin was killed in the river Brahmaputra recently (the decayed carcass was detected on May 16) by the poachers near Jahirpur area in Chhaygaon LAC in Kamrup district.
The full grown critically endangered animal, weighing around 200 kg had serious injuries on her back which led to her death, sources said.
According to Man & Wild, an environmental organisation of Assam, Gangetic River Dolphin (Platanista gangetica) is a critically endangered species under Schedule I of Wildlife Protection Act 1972 and killing of it is prohibited but till date government has not taken the case of poaching of Gangetic river dolphins as a serious matter and no significant attempt has been made to punish the culprits associated in the poaching of the dolphins. In other words the enforcement of the law is yet to be done , sources said. The Assam Government has declared the Gangetic river dolphin as State Aquatic Animal in order to protect the endangered animal. The IUCN, the apex conservation body of the world, has declared the gangetic dolphin as the most endangered aquatic mammal of the world.
Sources said the main population of the species is distributed in the river like Ganges, Brahmaputra, Kulsi, Sowonsiri, Meghna rivers and its population is fast dwindling due to rampant poaching, habitat degradation, accidental killings etc. Sources said that Ganges and its tributaries has the highest population of around 700 while Brahmaputra and its tributaries has population of around 250 in the Indian subcontinent. Sources said Kulsi river in Kamrup district of the State is one of the few smaller river where the resident population of the species are found which is significant as far as the tourist point of view is concerned. Sources said that the Kulsi river is the only river where highest density of the species is reported.
An official of Man and Wild told this correspondent that Gangetic river dolphin is an important bait for catching of a particular delicious fish called Naariah found in the Brahmaputra river and its tributaries. This is the reason for which a section of fishermen in the river Brahmaputra are poaching dolphins through various methods. Official further said that the fishermen in the Brahmaputra (not in Kulsi river) are becoming the professional poachers of Gangetic dolphin as dolphin oil has high output value with minimum of Rs 500 per kilogram of oil. The NGO has called upon the government to ban the sale of the Naariah fish in the markets in order to protect the gangetic dolphins.
The NGO said that fishermen have taken up various methods for poaching of the species among which killing by using the harpoons (harpoon is a pointed device/thing that can kill dolphin by penetrating into the body of the latter when it is thrown are prominent. Fishermen use the harpoons for both killing of gangetic dolphin and other fishes during the winter nights (also during summer) when the water of the rivers becomes crystal clear to see the aquatic species under the water. He said that whenever a fisherman sees a fish they throw the harpoons on the fish to kill it. Again, gangetic dolphins always come to the surface of the water to breathe at irregular intervals and when one dolphin comes out to the surface of the water the fishermen throw the harpoons into the body of the dolphin which results in killing of the species (as the harpoon penetrates into the body of the dolphins.)
NGO sources also said that accidental killing of the gangetic dolphin have also been occurring at an alarming rate because of the fact the fishermen populations are increasing and they are using nets made of advanced technology for catching fish.
Sources said the Gangetic dolphins does not use its eye for detecting or locating objects or prey ahead of it and instead they emit ultra sonic wave to detect the objects. The ultra sonic wave emitted by the dolphins is reflected from any object ahead of the dolphin and by analyzing the reflected wave the gangetic dolphins detect the objects, including its prey. This phenomenon is known as Echolocation Technique.
Sources said the most important case is that ultra sonic waves emitted by gangetic dolphins don’t gets reflected by the nets made of monofilament fibres which are largely used by the fishermen nowadays as the result of catching of the fish by monofilament nets is much higher than that of the ordinary nets. Hence, Gangetic dolphins easily get entangled in the nets made of monofilament nets as the dolphins fails to detect the nets ahead of it by using the Echolocation technique (as the ultra sonic wave do not get reflected by the monofilament nets).
The NGO has therefore requested the Government to ban nets made of monofilament fibre, which is detrimental as far as conservation of the Gangetic dolphins are concerned.