A giant goldfish was found in Lake Erie, Pennsylvania, raising concerns about invasive species.
The US Fish and Wildlife Service discovered the fish in July 2024 and recently shared the photo during Invasive Species Week. Experts warn that releasing pet goldfish into the wild can cause serious environmental problems.
Goldfish may seem harmless in tanks, but in the wild, they can grow much larger—sometimes as big as a football. Without predators to control their population, they multiply quickly and compete with native fish for food and space. They also stir up sediment in lakes, making the water murky and harming plants and other wildlife.
Additionally, wild goldfish can carry diseases and parasites that spread to native fish. This makes them a major threat to local ecosystems. The USFWS urges pet owners to find new homes for unwanted fish instead of releasing them into nature.
“Releasing a pet to the wild is never the right thing,” the agency warned. Many released pets do not survive, and those that do can become dangerous invaders.
