Wuhan, China – 380 individuals of porpoises were spotted along the Yangtze river signifies the declination of the species according to a 2006 research done previously.
During the survey of counting the porpoise via an acoustic device, only 160 of them were recorded along the expedition.
“There is a notable downtrend in the population size of the finless porpoise based on our observation,” said Wang Kexiong, deputy head of the research expedition and an associate researcher at the Chinese Academy of Sciences’ Institute of Hydrobiology (IHB).
The result from the 44 days and 3,400km round trip expedition between the Chinese cities of Yichang and Shanghai will be available after two months. This also includes the population of the porpoise in the particular region.
Based on the findings, there are few porpoises in the mainstreams compared to the wharf and port areas due to the amount of baits that attract the porpoises. Since porpoises rely on their sonar ability, their presence in the port areas could impose a threat for themselves due to the number of ships passing by . Rates are even higher in the Zhenjian-Jiangyin section of the Yangtze river with an average of 105 cargo ships passing by every half hour.
In Jiajang river, the population of porpoise is dense since the area is not disturbed by human activities. However, it is not conducive for the porpoise to navigate and reproduce in such place.
According to Wang, “The reason behind the scattered distribution of porpoise is because of the increasing shipping traffics leading to migration problem, amended hydrological condition projects and lower reaches as well as habitat loss.”
According to the WWF International website, “Findings on the number of population and variation trend are to be finalized according to a model that takes validity of calculation, density of distribution, width of the river, sailing length and areas covered into consideration.
Results obtained will be contribute to the drafting of Action Plan for the Yangtze Finless Porpoise Conservation by the Ministry of Agriculture and proposals regarding the conservation focused areas.
Led by China’s Ministry of Agriculture and organized by the IHB, WWF and Wuhan Baiji Dolphin Conservation Fund, the expedition first set sail on 11 November and comes only six years after the Baiji dolphin – another rare cetacean and close relative of the finless porpoise – was declared functionally extinct.
For more information, please click here.