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Some people release goldfish in places they don’t belong. They become invasive species. See how big invasive goldfish can get in a Minnesota lake.

Outside of their native land in eastern Asia, Goldfish are an invasive species. Some people free their pet goldfish in lakes and ponds. This is illegal. While pet goldfish remain small in captivity, they can grow more than 16 inches (40 cm) long in the wild. They take food and space from native fish. Wildlife officials believe there are millions of goldfish living in the Great Lakes and other fresh waterways throughout the United States.

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Making Connections


What do you like best about goldfish?


Have you read any other books about goldfish? What did you learn in those books that was not in this one?


There are many fish throughout the world. What other fish are good as pets?

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