Two "monster fish," or alligator gars, were recently discovered in the lake of a park in Ruzhou, Henan Province. To catch the fish, the whole lake, equivalent to 200,000 cubic meters of water, had to be drained so that there would be no alligator gars left to prey on other aquatic life in the future. Soon after the Ruzhou discovery, the fish were found in Beijing as well as Guangdong, Hunan, Shandong and Yunnan provinces, both in community ponds and in wild rivers and lakes.

The alligator gar, an exotic fish from North America with ferocious looks, prey on mild aquatic life, including most freshwater creatures living on waterweeds and algae, leading to the loss of biodiversity and deteriorating water quality of lakes and rivers.

Given the risk they pose to the local ecological environment, something has to be done. Whether it's encouraging the public to refrain from buying and keeping alien species or listing the fish as alien invasive species, the time for action is now. 

Wu Lichuan (Yangcheng Evening News): The practice of draining a lake over the course of one whole month to catch a particular type of fish may be a bit controversial, but it's the only choice. To preserve the local ecosystem, these predators must be located and eliminated.

Once entering rivers and lakes, alligator gars become bullies in the water, preying on other fish swimming in the same pond. The species has no natural enemies in China and swiftly procreates, posing a severe threat to local water systems.

Alligator gars are not banned from trading in China, and thus people are free to buy and sell them. But the public should know how to deal with them if or when they no longer wish to keep these "pet fish" at home. From a moral perspective, they should not simply release them into rivers and lakes and endanger their aquatic life.

Given these fish can wreak havoc on their surroundings, the law must step in to remove them.

Editorial (www.gmw.cn): The alligator gars found in Ruzhou and elsewhere have most likely been released by people who bought them as pet fish. At first they probably didn't realize how long the fish would grow, up to 3 meters, and how much it would eat. Anyway, their irresponsibly releasing these pets into the wild has caused huge trouble in the local ecosystem and catching these "monster fish" requires a lot of public resources. Those people who are found doing so must be warned and even punished.

Where are they? What kind of harm have they brought to local aquatic life? If they do pose a threat, a strict ban on their breeding, transportation and trading should be in order.

This year, the Ministry of Agriculture and Rural Affairs and other related departments have issued a number of documents guiding a nationwide survey on alien aquatic species, including alligator gars. Getting a clear idea of their location, quantity and the destruction they bring about will help to create targeted measures to prevent and eliminate them.

Ren Dapeng (www.huanqiu.com): The existing Chinese laws forbid people to release alien species into the wild, given they will pose a serious threat to the ecological environment. If you really can't afford to raise them, you can take them to the relevant departments who can properly deal with them.

If a certain alien species has already ravaged the local ecological environment, and the damage is beyond repair, then authorities must assess the risks posed by the invasive species. The current alien invasive species list can be extended on this basis.

Copyedited by Elsbeth van Paridon 

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