Experiment of the century: China fights mosquitoes with fish (3 photos + 1 video)
While the rest of the world is fighting mosquitoes with slippers and fumigators, the Celestial Empire has taken a proven but unexpected route — they have called up an army of mosquito fish for service. 
At first, this sounds like a joke, but knowing China, it could end in a new environmental disaster. I recall the infamous "fight against sparrows" in the 1950s, when Mao Zedong declared the birds enemies of the people for allegedly eating grain. The result: sparrows were almost exterminated, and the country was overwhelmed by an invasion of insects, which no one else could eat. The consequences were so tragic that the Chinese then panicked and bought sparrows abroad.
Now they are fighting mosquitoes. But the Chinese authorities decided: enough chemicals, let's release natural predators. In July, when more than 4,000 cases of chikungunya fever were recorded in the city of Foshan (Guangdong Province), local officials announced the mobilization of... fish. 
More than 5,000 gambusia, a small but voracious fish capable of killing up to 200 mosquito larvae per day, have been released into ponds and ditches in Foshan parks. According to experts, the larval population should decrease by 60% in three months. Moreover, all this, in theory, is done without harming the ecosystem, without chemicals, without odor, and without threat to cats that drink water from the ditches. In the Changcheng district, where the scheme is being implemented, a couple of weeks have passed since the launch of the fish pass, and the results already show a decrease in the density of mosquitoes and larvae in 78% of settlements and villages.
Gambusia is not a new thing. These fish have long been used in Asia and South America to fight malaria mosquitoes. But releasing them into the city on the scale of a "small biological army" is a new step. 
According to the Chinese authorities, the fish are a more environmentally friendly alternative to chemical insecticides. Instead of filling reservoirs with poison, they simply release the fish there and wait for the effect. Well, while the gambusia bite into the mosquito youth, local services set traps, send out fines of up to 10,000 yuan for stagnant water and increase the number of beds with mosquito nets in hospitals.
This whole story is, of course, a shining example of ingenuity. But here we cannot help but remember that the gambusia is an aggressive invasive species. In the absence of natural enemies, it can begin to displace local fish, upsetting the balance. That is, if the experiment is not controlled, the Chinese will get a "war with sparrows 2.0", only underwater.
In addition, the story with mosquitoes is not at all about how to kill all the insects, but about how to prevent stagnant water in flowerpots, on roofs and in pallets. And this is difficult in China, as elsewhere.
