File photo: Farm sturgeons
A hydroelectric plant in Hubei may have started an ecological crisis when a flood discharge disrupted sturgeon net cages used for fish farming. Nearly ten thousand tons of non-native and crossbred sturgeons escaped from their cage, according to a report by Yangtze River Office of the Ministry of Agriculture.
Geheyan Dam
The Geheyan hydroelectric plant discharged flood into the Qingjiang River, a branch of Yangtze River. The sturgeon eventually made their way into the Yangtze River, where they pose a threat to the delicate ecology. Leading scientist from the Chinese Academy of Fishery Sciences, Wei Qiwei, told thepaper.com that the possible number of spilt sturgeons is enormous. He estimated the number might exceed the sum of the standing biomass of fish in the Yangtze’s mainstream.
The breached farm fish nets
The danger here, he explained, is that this type of sturgeon is carnivorous and will prey on other fish species. Additionally, once the sturgeon’s form shoals, not only will they snatch up other fish’s food, they’ll also aggressively fight for territory. They’ll progressively push other fish out of the ecosystem, ultimately replacing them all together.
There are over 300 types of wild fish in the Yangtze. Each one has struck their own balance with the ecosystem over thousands of years of evolution. How this influx of an alien predator will affect this balance, and to what extent, remains a serious concern.
Besides an imbalanced ecosystem, there is yet another fear: genetic pollution. The critically endangered Chinese sturgeon in the river may mate with the farm fish, making a purebred Chinese sturgeon nearly impossible to find.