No matter what your opinion on ex-situ conservation is (and they can be varying), there is no doubt that the project to “save” the critically endangered Yangtze finless porpoise from extinction is reaping some early rewards.
This little porpoise is restricted to the middle and lower reaches of China’s Yangtze River (including two adjoining lakes) but as a result of habitat degradation on an unprecedented scale, an increase in river traffic and fishing effort – resulting in fatal collisions and entanglement in fishing gear – the “natural” population of this sub-species has declined dramatically over the past few decades. With only an estimated 1,000 individuals left of the world’s only freshwater porpoise, if they are to be protected for future generations then the time to do something is now.
Back in the 1990’s, the Chinese Government declared the Tian-E-Zhou Oxbow (an old natural channel now cut off from the Yangtze River proper) a natural ex-situ protection site for the porpoise and moves were made to capture and relocate several individuals to the site. Over the years a few more individuals have been captured and relocated and a recent census completed in November 2015 showed that the population had also increased naturally over the past 5 years by approximately 108% – going from 25 animals in 2010 to 60 in 2015.
The idea was/is to use these individuals as a “seed population” which they aim to reintroduce back into the Yangtze River (their natural habitat) when conditions have improved. This all sounds impressive and very promising for this critically endangered little porpoise however … the main problems with this plan are twofold.
What happens when the “reserve” reaches capacity? it is thought that this particular site can only hold 80 – 100 individuals (based purely on prey availability) so it’s almost full already but with a second site already identified where another 120 individuals can flourish …. will they just keep finding new sites? Or will they give up after a few sites are full and be happy that they’ve “saved” the sub-species? If so, what happens to all the newborns? If the population growth over the past few years is anything to go by then these little guys will keep on reproducing (and obviously dying but perhaps not at the same rate as they’re being born now that the threats have been removed) … so what happens when this, and the next site is full?
Additionally, and possibly most importantly (as this is the underlying premise of this idea in the first place) will they ever clean up the Yangtze River sufficiently enough to release these individuals back to the wild? Or are these select few individuals doomed to live a life in a semi-natural environment whilst being a sorry reminder of one of the sub-species that “used” to roam our planet? Will they just become another tourist attraction where they have to be fed fish to keep them alive?
Cleaning up and restoring their natural habitat is the only way to truly save the sub-species but sadly … at this juncture … any small steps towards ensuring yet another species (or sub-species) of cetacean doesn’t go extinct at the hands of mankind can surely only be a good thing? Or can it?