GUWAHATI, Nov 9 - Even after five months of the Baghjan blowout, the fish diversity of the Maguri-Motapung wetland ecosystem remains severely affected � corroborated by a drastic decline in its fish diversity, with some species completely wiped out. Not just diversity, the presence of fish in the wetland has also come down substantially, as borne out by low volume of catches post the disaster. This in turn has badly impacted livelihood of local fishermen.
This was the observation of the NGT-appointed committee probing various aspects of the Baghjan gas well blowout in its latest assessment report of the environment and biodiversity of the affected landscape.
�The pollutants from the blowout incident seriously affected the breeding season of fishes. The Mystus species was found in gravid condition, but from last March to July end, no fish seedling of the species was found in the (Maguri-Motapung) beel which clearly indicated that their breeding cycle was impacted,� the report submitted to the NGT on November 3 stated.
Besides, the report added, sudden change in body colour was also noticed for different fish species. �The dead fishes were full of mucous layer with a different kind of smell. The WII (2020) mentioned significant increase of the PAH in the water of Maguri Beel that caused death of different fish species,� it said.
The report also mentioned that the damage to the biodiversity and the environment would be long term and that those would have to be assessed over a long period of time. As per the report the planktons have noticeably declined in the Maguri-Motapung Beel.
In a study during the June-July period this year only 11 species of phytoplankton and 13 species of zooplankton were recorded from the site that reported a rich phytoplankton (61 species) and zooplankton (210) diversity not so long ago. It was also assessed that Maguri has 87 species of ichthyofauna, out of which only 22 species were found in the survey.
Stating that the team recorded 35 varieties of dead fish species belonging to 13 families, the report said that among the dead species, 22 species were under lower-risk near-threatened category as per IUCN status.
The report further said that a recent study by the same team in October 2020 revealed that some of the prominent species namely Ompok pabo, Nundus nundus, Ailia coilia, Pseudeutopius atherinodes, Channa aurantimaculata, and Danio rerio were completely wiped out from the Maguri-Motapung wetland area which is also part of the greater Dibru Saikhowa National park ecosystem.
Apart from the wetland, the nearby ponds were also affected due to drastic fall in dissolved oxygen level in water. �On June 26, 2020, it was noticed that heavy toll of fishes were coming to the upper surface of water for oxygen. They exhibited lethargic and irregular body movement. Large number of fishes died on the very next day and it continued till June 28, 2020,� the report said.
According to the report, a majority of the fishermen who earned on an average minimum Rs 2,000 per day had to stop their main occupation up to three months, causing heavy financial loss to the local fishing community.
In this major river dolphin habitat, sighting of the aquatic animal has also come down drastically, with just two numbers observed on October 18 along the river stretch from Sobha Nallah (River Dangori) to Kalmi Nallah (River Dibru).
�The same team had observed 13 numbers of the river dolphins at Koliapani Ghat on June 30, 2020. It was mentioned in the preliminary report that encounter rate of Gangetic River Dolphin in the area has decreased by 89 per cent post the blowout and also the death of an individual,� it added.