(WJW) – There is a new warning about goldfish in the Great Lakes. A study published in the Journal of Great Lakes Research tracked goldfish in Lake Ontario to learn more about their impact on the environment.

“There are literally millions of goldfish in the Great Lakes,” Nicholas Mandrak, a biological scientist at the University of Toronto Scarborough, told the New York Times.

While goldfish remain tiny in a fishbowl or tank, in the wild, it’s a different story.

According to National Geographic, a goldfish can live more than 40 years in the wild, growing to as much as 16 inches and weighing more than 5 pounds at their biggest.

The study tracked goldfish movement for two years, starting in June 2017.

While the goldfish have thrived, the study shows native fish compete with them for vegetated wetland habitat.

The study showed that an increase in goldfish coincided with a decrease in the carp population.

“With increasing water levels and climate change favoring species like goldfish that can survive in extreme environments, alternate control measures will be important to protect spawning areas targeted by invasives that are also important for native fishes,” the study says.

Goldfish are native to Asia and are believed to have been “both intentionally and accidentally” introduced to the Great Lakes in the 90s, according to the research.

There is also new evidence, they say, that goldfish have the potential to move greater distances than previously thought, which has implications for invasion into new areas.