The size of invasive goldfish is growing.(Photo: IFL Science.)
Goldfish are considered as invasive species, because they compete for food sources with native animals in the area. Wildlife regulators worry that they can extend their living environment to other river and lake systems, where vulnerable fish species exist. At that time, native species are at risk of being unable to live there, leading to a reduction in biodiversity and natural ecosystems that will be permanently affected.
The city of St Albert in Canada used all measures but still could not destroy the goldfish.
In 2015, the city government decided to remove the water to ensure the lake was frozen completely to destroy the goldfish. But when spring comes, the water in the lake melts and the goldfish still survive.
In 2016, they used electric shocking to kill fish but still did not work.
Recently, the city government sprayed a special chemical to kill goldfish.