THE CRIMES: Displaces native fish. Feeds on fish eggs and young fish. Spawns multiple times a year.
DESCRIPTION: Bottom-dwelling fish slightly resembling a large tadpole with a big head, narrower body, frog-like raised eyes and thick “lips.” Body is mostly slate gray and mottled with black to brown spots. It grows from 15 – 30.5 cm (6-12 in). A fused pelvic fin forms a suction disk.
Where are you from?
I came from the Black and Caspian Seas.
How did you get here?
Me and my goby buddies hitched a ride on a transoceanic vessel to the St. Clair River, the channel between Lake Huron and Lake St. Clair around 1990. The St. Clair River was fine for a few years but it got a little crowded in 1993 since my goby relatives populate so quickly. We have spread to all of the Great Lakes since then. Now, after menacing the Great Lakes, we are heading for the Mississippi River.
Whats your problem?
Can I help it if I’m so competitive and aggressive that I push out other bottom-dwelling fish such as mottled sculpin, log perch, and darters? They lose out on their preferred habitat and spawning areas. Being a “lowlife,” I feed on bottom-dwelling invertebrates, fish eggs, and other small fish in rocky, cobble surroundings. Like other animals, I defend my spawning area and don’t allow other native fish near them.
Can I help it that I also have a well-developed sensory system that allows me to eat in the dark, which gives me the edge over the native fish?
Cut me a little slack! I do eat those menacing zebra mussels. I can devour more than 75 zebra mussels a day. Fortunately for me, zebra mussels reproduce so fast that I’ll always be able to find those tasty little mollusks. The problem for you humans is that although there are plenty of us around, there just aren’t enough of us to eat all those zebra mussels.
How can we control you?
Ballast dumping regulations in North America are one way of preventing us from spreading to other waterways. It’s also important to educate anglers and others to avoid spreading us accidentally. We should not be used as bait! Bait buckets should be dumped only in areas where they were filled, and we should not be brought home to live in your aquariums.
Reward: The honor of protecting our water resources A healthier environment and more opportunities to enjoy our natural areas.