Mutant Goldfish Takeover: Minnesota Lake Becomes Feeding Ground for Zoo Animals

In a unique twist to an environmental crisis, a town in Minnesota has found a way to use the influx of invasive goldfish in a local lake to feed zoo animals. The town of Edina has been grappling with a goldfish takeover of Lake Cornelia, with the population exploding and the fish even mutating into much larger versions.

Last year, in 2023, around 50,000 of the critters were removed from the lake, and so far in 2025, over 8,500 have been caught. The surprising part is that despite the declining numbers, the total weight of the catches remains about the same, as some of the goldfish have doubled in size through mutation.

This has rendered the lake unusable for residents who once enjoyed it for recreation and fishing. To combat the issue, the town has partnered with the Minnesota Zoo, which now buys the captured invasive fish to feed to animals like bears, sea lions, and otters. While the brown bears, sea lions, and otters have welcomed the new delicacy, the black bears, leopards, and tigers are still getting used to the strange new food.

The mutant goldfish are not only a nuisance but also a threat to the local ecosystem. They disturb the lake bottom, making the water murky and stirring up phosphorus that can contribute to dangerous algae blooms. Invasive species like these can wreak havoc on the environment, consuming resources and disrupting habitats.