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Oversized goldfish are taking over a Burnsville lake, causing issues for local fish

Jul 13, 2021 07:45AM ● By Editor
Large goldfish, released by pet owners into bodies of water, are contributing to poor water quality in some lakes and ponds in Minnesota.  Photo: City of Burnsville, Minn.

By Jaclyn Diaz from Minnesota Public Radio News - July 13, 2021 

Pesky, oversized goldfish are causing problems in Minnesota.

Authorities in Burnsville have urged residents and owners of pet goldfish not to dispose of the family pet in lakes and ponds. The city tweeted a warning that doing so has resulted in the takeover of one local lake by overgrown goldfish.

"They grow bigger than you think and contribute to poor water quality by mucking up the bottom sediments and uprooting plants," authorities wrote on Twitter. "Groups of these large goldfish were recently found in Keller Lake."

It's not the first time Minnesota lakes became overrun with oversized goldfish.

Last November, wildlife officials found thousands of goldfishswimming in Big Woods Lake in Chaska, a suburb of Minneapolis. A team had to remove a truckload of 500,000 of the goldfish, due to environmental issues caused by the fish.

The problem has cropped up in Boulder, Colo., and Lake Tahoe, Nev., too, where researchers found thousands of goldfish in local lakes in both areas years ago.

The act of dumping unwanted goldfish into a local pond is actually illegal in most states, including in Minnesota where the problem has recently cropped up.

It's considered "illegal fish stocking," and its turned up in every corner of Minnesota. Doing so upsets the balance of existing natural, fish communities and spreads disease.

Goldfish are considered invasive species that uproot underwater plants and compete with native fish for food and shelter. Speedy reproducers, the fish live up to 25 years, and are a real pain to remove, according to Carver County officials. 

If you're a pet owner and realized a decadeslong commitment with your goldfish is not what you had in mind, the U.S. Fish and Wildlife Service recommends putting Goldie up for adoption. Another alternative is to contact a local veterinarian or pet retailer to find ways to humanely dispose of the fish, without causing harm to native fish species in your local neighborhood.

To see the original post and read related stories, follow this link to the MPR News website.

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