Walking through a pet store, you may notice a warning below the goldfish which says "NYS invasive species - harmful to the environment". This, is because 40-50 million goldfish have infested Lake Ontario, which can cause issues in the ecosystem.
A large reason why these goldfish are in the ecosystem is because fish owners dump the animals into large bodies of water. When the fish survive, they end up integrating themselves into the environment.
"There's always a chance that it (an invasive species) could end up disrupting ecosystem function or have some kind of impact" Buffalo State Professor Chris Pennuto said.
Pennuto says if you can no longer care for a fish, you can try to find another home for it in an aquarium. If no other options are available, he says you can consider humanely killing the fish. Pennuto says you should not release it into the wild. Those fish that are released could lead to major damage.