Survey suggests Indus dolphin wiped out in upper rangePakistan
KARACHI: A recent survey suggests that the Indus river dolphin might have been locally wiped out between Jinnah and Chashma barrages as the team couldn’t spot a single specimen. Both barrages are located in the Mianwali district of Punjab.
The survey team included experts from the World Wide Fund for Nature-Pakistan, Zoological Survey of Pakistan (ZSP) and provincial wildlife departments.
This is the second year in a row that WWF-Pakistan has conducted assessments to investigate the status of this species in different locations within its historical population range.
The ultimate objective of these assessments is to help make informed decisions for conservation planning.
This time the survey was carried out far north of the dolphin’s range from Jinnah to Chashma Barrage in the Indus.
The survey covered more than 70km area, which is close to the foothills of the Himalayas and has not been surveyed since 2006.
“Local communities interviewed during the survey supported the finding, also indicated by previous hypothesis that the Indus river dolphin is declining in the upper reaches of the Indus River,” said Dr Babar Khan, director wildlife at the WWF-P.
According to him, previous surveys estimated less than five dolphins within this river section, which was the smallest known sub-population of the species.
“There was concern that because of the small size of the population it may be wiped out in the near future,” he explained, adding that the survey methodology was consistent with the previous assessments used since 2001 which helped to obtain reliable and comparable data.
Among the potential factors which might have contributed to the range decline, he pointed out, included low discharge of the river during the dry season and habitat fragmentation by irrigation barrages.
“Reduced flow has a direct impact on the dolphins as this limits the physical habitat available for them, changes the depth of river, flow velocity and temperature of the water,” he said.
It is important to mention that the Indus river dolphin is an endangered freshwater cetacean and endemic to the Indus River system. The species are found in five sub-populations separated by barrages on the Indus.
According to Dr Gill Braullik, cetaceans expert and member of IUCN Cetacean Specialists Group, the dolphin population is now confined to just 20 per cent of their natural habitat range due to the construction of numerous dams and barrages along the Indus.
Dolphins are also threatened by stranding in irrigation canals and accidentally becoming caught in fishing nets.
Additionally, rapid industrialisation has significantly contributed to increased surface water pollution in the country, as over 90pc of industrial and domestic effluent make their way to the river untreated.
The situation is severe in the Indus tributaries which pass through major industrial areas as they carry even higher loads of pollutants than the main river itself.
Lack of periodic and proper mechanisms of water quality assessment of the river further intensifies the problem to identify those sections of the river which carry higher loads of waste.
Khalid Ayaz Khan, the director general of the Punjab Wildlife and Parks Department, said that a development project along the Indus had been initiated to establish three dolphin rescue and monitoring stations, a satellite telemetry study and translocation of stranded dolphins to the stretch of Indus River between Jinnah and Chashma barrages.
“This will help in the conservation of endangered fauna of the area, particularly the Indus river dolphin,” he said.
Published in Dawn, July 11th, 2018
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