The U.S. Fish and Wildlife Service is urging the public to refrain from releasing goldfish into local lakes, ponds and streams when they are no longer desired as pets, but instead seek alternative solutions such as returning them to the pet store or contacting a local aquarium or fish rescue organization for assistance.

In the wild, goldfish exhibit invasive characteristics that cause significant harm to local ecosystems. Omnivorous in nature, they thrive in diverse environmental conditions and are capable of rapid growth, exceeding four pounds in weight and a foot in length. At that size, they have no natural predators.

As bottom feeders, goldfish disrupt the delicate balance of aquatic ecosystems by stirring up sediment, uprooting plants and muddying the water. Their spawning frequency, which occurs several times a season, can lead to rapid population expansion. Goldfish also harbor parasites and diseases against which native fish possess no immunity.