Population status, threats and conservation of the Yangtze finless porpoise

Accelerating population decline of Yangtze finless porpoise (Neophocaena asiaeorientalis asiaeorientalis)

“…Following the probable extinction of the Yangtze River dolphin or baiji (Lipotes vexillifer) in the first decade of the twenty-first century (Turvey et al, 2007), the Yangtze finless porpoise has become the only cetacean species to be found in the Yangtze River. However, progressive declines in the number of porpoises observed during boat surveys (Zhang et al, 1993;Wei et al, 2002;Zhao et al, 2008), drastic loss of suitable habitats resulting in apparent distribution gaps in the formerly contiguous population (Wang et al, 2000;Zhao et al, 2008;Wang, 2009), and low levels of genetic diversity (Yang et al, 2002(Yang et al, , 2008bXia et al, 2005;Zheng et al, 2005) all suggest that the Yangtze finless porpoise may follow the baiji and also become extinct in the wild in the near future. The apparent decline of the porpoise population in the Yangtze mainstem, from more than 2550 animals in 1991 (Zhang et al, 1993) to fewer than 1225 animals in 2006 (Zhao et al, 2008), raises an important question: how many years do we have left to reverse the decline of this cetacean?…”

“…This decline is being driven by high levels of mortality resulting from anthropogenic impacts such as incidental by-catch in legal and illegal fishing gear, ship collisions, widespread sand dredging, pollution, and water development projects along the middle and lower reaches of the Yangtze River (Wang et al, 2000Yang et al, 2002Yang et al, , 2008aXia et al, 2005;Zheng et al, 2005;Zhao et al, 2008;Wang, 2009). The Yangtze is known as the ''golden channel'' of central China, and supports the livelihoods of hundreds of millions of people through agriculture, aquaculture and industrial activities.…”

Establishment and characterization of fibroblast cell lines from the skin of the Yangtze finless porpoise

“…Both species have been dramatically affected by human activities and are facing an acute and severe situation (Wang 2009). Most recently, the Yangtze River dolphin (L. vexillifer), an obligate freshwater odontocete known only from the Yangtze River system, has been declared as "likely extinct" (Dalton 2006;Guo 2006;Turvey et al 2007).…”

“…Its population has been decreasing annually at a rate of 5% or more (Zhao et al 2008). An exhaustive survey conducted in 2006 by experts from seven countries found that the population of the Yangtze finless porpoise in the main river stem was approximately 1,000∼1,200 individuals, which was less than half of the population size estimated from the surveys from the year 1984 to 1991, and that the distribution is becoming more fragmented (Zhao et al 2008;Wang 2009). Immediate, proactive, and effective measures must be taken to prevent the Yangtze finless porpoise from following the fate of the Baiji (Wang et al 2006).…”

“…Maintaining and, if necessary, increasing biodiversity is the prime aim of conservation research (Leon-Quinto et al 2009;Sutherland et al 2009). Three conservation measures (in situ, ex situ conservation, and captive breeding) have been adopted to maintain and restore porpoise populations since the early 1990s by a Research Team of Conservation Biology of Aquatic Animals at the Institute of Hydrobiology, Chinese Academy of Sciences (Wang 2009). As a complementary supporting program to reinforce these three strategies, it is of significant scientific importance to establish a biological resources bank (Wiidt 1992;Holt and Pickard 1999;Comizzoli et al 2000;Leon-Quinto et al 2009), such as, the preservation of individual animals, semen, embryos, blood, tissue, cells, genomic libraries, and cDNA libraries.…”