Giant, invasive goldfish are taking over lakes and ponds around the country. One Minnesota county pulled out 100,000 last year.

Residents in Minnesota are being reminded not to dump their goldfish in ponds and lakes, and for good reason. Someone fishing in Burnsville recently pulled a giant goldfish out of Keller Lake – an odd sight, yet one that is becoming common in the United States. 

In a tweet on Friday reminding residents not to dump goldfish, Burnsville officials said goldfish "grow bigger than you think and contribute to poor water quality by mucking up the bottom sediments and uprooting plants." They said groups of large goldfish were recently found in Keller Lake. Officials in Burnsville, a suburb of Minnesota's Twin Cities, initially found 10 fish in Keller Lake – but this week, 18 additional fish were found. Some were 18 inches long and weighed about 4 pounds, according to the Associated Press.