The finless porpoise known for its mysterious smile is the cousin of a now extinct dolphin species called the Baiji dolphin. Both do not have a dorsal fin. The finless porpoise lives in coastal waters across Asia and the Far East. It also lives in the Yangtze River. Its population is decreasing and it is categorised as “Vulnerable” by those experts whose job it is to categorise species by their vulnerability to becoming extinct.
In short, the finless porpoise is gradually becoming extinct for a variety of reasons. One immediately comes to mind which is that the Yangtze River is badly polluted with plastic as it discharges 333,000 metric tons of plastic into the oceans annually. A staggering amount. A study found that a common type of microplastic (MP) waste found inside finless porpoises were threads indicating that this was waste from the textile industry.
You can imagine what it is like swimming in that river as a finless porpoise. They are bound to ingest a lot of plastic. Of course, the waters around the coast of these regions is also going to be heavily polluted with plastic as the rivers discharge the plastic into the oceans.
So, this marine species is particularly vulnerable, as I see it, to polluting substances discharged into the major rivers which are then washed into the oceans.
Ninety percent of all ocean plastic is carried by just 10 rivers, eight of which are found in Asia and the Yangtze River in China is the worst culprit.
You don’t have to read far on the Internet to find stories of small whales, large whales and other marine wildlife including marine birds dying of plastic pollution because they are ingesting it. They end up being unable to digest real food because their stomach is full of plastic. They die of starvation.
There are other ways for the finless porpoise to die, a major one of which is through “bycatch”. They are caught up in nets such as gillnets. More than 3.5 million gillnets were estimated to be in use in the early 1990s in Chinese waters which excludes the fisheries operated in Taiwanese waters. There are also killed by shipping, habitat loss and degradation of the habitat.
There’s simply less habitat for the finless porpoise. Although, pollution is considered to be a serious threat and has been known about since the late 1990s.
Other threats to the finless porpoise include pollution from industrial and military effluents, agricultural and forestry effluents and urban wastewater. The much-loved finless porpoise has to live in this filthy water.
The story is little different off the coast of Gujarat, India. Plastic waste is known to claim the lives of finless porpoises when they are washed ashore with plastic bags in their stomach. In one example a finless porpoise was found to have four thick plastic bags inside it stomach which blocked off passage of nutrients in the gastrointestinal tract.
