Invasive goldfish population spikes in Chaska chain of lakes

Goldfish aren't good for Minnesota's waterways.
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Thousands of goldfish have been found in Chaska-area lakes and it's quite the problem. 

The fish were found by Carver County Water Management Organization during a routine inspection Tuesday at Big Woods Lake, which it described as a "goldfish infested pond." The Star Tribune reports their likely numbers are in the thousands.

"Despite being a popular pet, they are an invasive species when released into the wild with no natural predators. Please keep them in your tanks and out of our lakes!" the water management group said

The goldfish were found in an inlet channel around the Grace Chain of Lakes in Chaska. Staffers spotted the fish last year, but "the numbers have grown significantly" and they suspect the goldfish have spread to other lakes in the chain, which includes Lake Grace, McKnight Lake, Lake Jonathan, Big Woods Lake and Lake Hazeltine.

"Goldfish are an invasive species, related to common carp, that are known to cause water quality issues," says Carver County Water Management Organization. "We do not want these species to spread to other lakes and streams." 

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How'd the goldfish get there? The answer isn't certain, but it's likely that someone with goldfish as a pet put them in a lake.  

Female goldfish can lay thousands of eggs at a time, which can lead to fast population growth like what's being seen in Chaska. 

It is illegal in Minnesota to transport live goldfish out of state waterways. Anglers can fish for them with a hook and line, but they have to be dead to be transported. Transporting them while they're alive increases the risk of the invasive species spreading. 

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