Continuing with the theme of "river" dolphins, it's now time to learn more about the lesser known finless porpoise (Neophocaena phocaenoides).
The charming finless porpoise is very much a coastal species, predominantly found in salt water areas of the Indo-Pacific region. However, a small and endangered population of the porpoise inhabits the infamous Yangtze River and its tributaries. For this reason we have included the porpoise in the river dolphin series of blogs! Very little is known of the species, as is common with most of the cetaceans covered in this series of blogs, but the plight of the baiji (Yangtze river dolphin) from the Yangtze River has drawn obvious attention towards the oddly named “river pig”.
Much debate has occurred over recent years over the genetic distinction of a number of sub-species of finless porpoise. Many populations are geographically isolated and this has led to the rise of the currently recognised three sub-species. Of which, the Chinese population of freshwater dwelling porpoises is one – Neophocaena phocaenoides asiaeorientalis.
As with other species of porpoise, N. phocaenoides is not known to be overly acrobatic and shies away from boats and human disturbance. The tragedy of the Yangtze River population is that the levels of human disturbance and boat traffic in the region are so high that many individuals now readily approach boats. They have therefore become more vulnerable to the usual suspects of by-catch in fishing gear and direct boat collision. Unfortunately, their ‘cute’ looks and approachable behaviour have also led to the river population being exploited for the aquarium trade. In conjunction with all the same impacts that pushed the baiji to extinction in recent years, this represents some the most irresponsible of practices the aquarium trade takes part in worldwide.
However, the tragic loss of the baiji has spurned more rapid action in conserving the finless porpoise population of the Yangtze River. The Tian-e-Zhou Oxbow Nature Reserve, an area of wetland in the Yangtze basin near Shishou City, was originally intended for the baiji. More recently it has been adopted as a ‘safe haven’ for the finless porpoise in which 28 individuals live. This is an example Chinese conservationists wish to follow in the fight to conserve the river dwelling populations by using other sanctuaries and reserves that were previously set up for the baiji.
The Tian-e-Zhou population is by no means a strong population and with the only other ‘stronghold’ of finless porpoises in China (in Poyang Lake) coming under threat from dredging activities, their future looks bleak. Chinese conservationists have, however, insisted that the population can be saved if sufficient action is taken immediately. Sand dredging in Poyang Lake has provided a quick and sizeable cash injection into the area. Whilst the lake holds a quarter of all finless porpoises found in China, the boats are the primary cause of an extremely high porpoise death toll. If sufficient protection is put in place for the porpoises and the dredging activities are more strictly controlled, the future of the Poyang finless porpoises may well be restored.
As with many other species of cetacean, their future may rely on tourist revenue replacing the income streams created from the impacting practices, such as sand dredging and fishing. This in itself holds many obstacles but WDCS will be at the forefront of ensuring new cetacean watching programmes are conducted responsibly and to the benefit of the animals the world over.