Football-sized goldfish found in Minnesota lake can hurt ecosystem, town warns

Authorities in a Minnesota town are urging residents to not dump their pet goldfish into ponds or lakes after finding overgrown goldfish the size of a football.

Why it matters: A pet goldfish freed in a waterway is an invasive species that can quickly reproduce, outcompete native species and destroy a habitat. Dumping unwanted goldfish into a local pond is illegal in most states, including in Minnesota, where the problem has recently increased.

The big picture: The City of Burnsville tweeted Friday that large groups of goldfish were found at Keller Lake, and believes local residents could be the cause. 

• Goldfish can live up to be 25 years old, and once they are dumped into a waterway, there's no easy solution exists to remove an invasive species like goldfish, according to Minnesota officials.