Finless Porpoise - Conservation

Conservation

On the IUCN "red list" database of endangered species, the finless porpoise is listed as "vulnerable" due to apparent declines in the best studied populations in the Sea of Japan, and the Yangtze river basin. The fresh water subspecies in the Yangtze river is characterized as endangered. Since this species remains in coastal waters, it has a high degree of interaction with humans, which often puts the finless porpoise at risk. Like other porpoises, large numbers of this species are killed by entanglement in gill nets. Except for being briefly hunted after World War II due to the lack of seaworthy fishing boats, finless porpoises have never been widely hunted in Japan. It is a species protected since 1930 at the area around Awajima Island, Takehara and this coverage had since been extended to all Japanese coastal waters. The primary danger to the species is the environmental degradation. In addition, unlike other members of this family, finless porpoises have lived in captivity for over 15 years.

There are no well-established estimates of the animals' abundance. However, a comparison of two surveys, one from the late 1970s and the other from 1999–2000, shows a decline in population and distribution. Scientists believe this decline has been ongoing for decades, and the current population is just a fraction of its historical levels. A 2006 expedition estimated fewer than 400 animals survived in the Yangtze River.

At the end of 2006, an estimated 1400 porpoises were left living in China, with between 700 and 900 in the Yangtze and another 500 in Poyang and Dongting Lakes. The 2007 population levels were less than half the 1997 levels, and the population is dropping at a rate of 7.3% per year. Preliminary results of a 2012 study indicated that the Yangtze population continued to decline.

Current conservation efforts were undertaken alongside those for the recently functionally extinct baiji. In 1990, five individuals were relocated to the Tian-e-Zhou Oxbow Nature Reserve, and now a population of 28 currently inhabit the lake.

Sand dredging has become a mainstay of local economic development in the last few years, and it is an important source of revenue in the region that borders Poyang Lake. At the same time, though, high-density dredging projects have been the principal cause of the death of the local wildlife population.

Dredging makes the waters of the lake muddier, and the porpoises cannot see as far as they once could, and have to rely on their highly developed sonar systems to avoid obstacles and look for food. Large ships enter and leave the lake at the rate of two a minute, and such a high density of shipping means the porpoises have difficulty hearing their food, and also cannot swim freely from one bank to the other.

The Finless porpoise is listed on Appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS). It is listed on Appendix II as it has an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements.