The round goby: Hamilton Harbour's unwanted guest

They look harmless enough, like something you might see in a big goldfish bowl.

But the round goby is no one’s pet, an uninvited guest of the worst kind, that has been wreaking havoc in the Great Lakes and causing all kinds of ecological mischief in Hamilton Harbour.

McMaster University professor Sigal Balshine has been studying gobies for several years and says “the speed of the invasion has shocked scientists.”

It’s believed that round gobies came to North America in the ballast water of ships from southern Europe. They were first noticed by anglers in the St. Clair River in 1990, and since then have worked their way into all the Great Lakes. They were first reported in Hamilton Harbour in 1999.