Invasive Species in Quebec: What Every Angler Needs to Know

You've probably seen the signs at boat launches, the ones with the round goby and the zebra mussels and the warnings about cleaning your trailer. Most guys walk right past them. They've got fishing to do. The signs will be there when they get back. Those signs exist because the problem is already here. The only question is what comes next and whether you're going to help spread it.

Zebra Mussels: The One You Can't Miss

These are the small striped shells you scrape off your boat hull every fall. Two to four centimetres. They cling to everything, rocks, docks, other mussels, your anchor rope. A single female releases up to one million eggs per year.

Each mature mussel filters a litre of water per day. They strip the plankton out, the stuff native species need to eat. Then they excrete nutrients that feed toxic algae blooms. The water gets clearer, which sounds good, but clear water means more sunlight reaches the bottom, which means more aquatic plant growth, which means more habitat change. Nothing about it is neutral.

On the St. Lawrence near Montreal, zebra mussels have covered spawning beds that used to produce walleye and yellow perch. The eggs can't settle. The fish move on. The fishery changes.

You'll also find quagga mussels, the zebra mussel's slightly larger cousin. Rounded shell instead of flat. Same problems, slightly different look.

Round Goby: The Bottom Feeder Nobody Invited

This fish came over in ballast water from the Black Sea and Caspian Sea. It's now in the Great Lakes and spreading. Quebec has confirmed populations in the St. Lawrence. It's only a matter of time before it pushes further north.

Round gobies look like a cross between a sculpin and a bullhead. They have a black spot on their first dorsal fin. They sit on the bottom and guard their nests aggressively. They eat small native fish, their eggs, and zebra mussels. Yes, they eat zebra mussels. That's the problem, they thrive on the very thing killing native habitat.

• A goby can spawn multiple times per season
• A single female produces thousands of eggs
• The young grow fast and outcompete native darters and sculpins for food and space

If you catch a round goby, do not throw it back. Kill it. Report it to the provincial government.

The Ones That Aren't Here Yet, But Could Be

Asian Carp

Bighead and silver carp filter plankton like zebra mussels, but these fish can hit forty kilograms. Silver carp jump out of the water when boats pass, they've injured people and knocked anglers out of boats. Asian carp have been moving up the Mississippi and its tributaries for years. They're in the Chicago waterway system. Electric barriers keep them out of the Great Lakes, for now. If those barriers fail or someone transports them intentionally, the St. Lawrence is next.

Snakeheads

These fish breathe air and walk across land. No exaggeration, they move over wet ground from one body of water to another. They have teeth. They eat everything. They're established in parts of the United States. Quebec doesn't have them yet. Let's keep it that way.

What You Can Do About It

The Clean, Drain, Dry protocol isn't optional. It's the only thing stopping you from becoming a delivery system.

• Clean, Inspect your boat, trailer, and gear before you leave the launch. Pull off every piece of plant material. Scrape off every mussel you can see. Pay attention to your anchor rope and the crevices around your trailer bunks. Mud carries larvae. Plants carry fragments.
• Drain, Open every plug: bilge, livewell, motor, ballast bags. Zebra mussel larvae (veligers) are microscopic, you won't see them. They'll swim out when you drain your water. If you don't drain, they'll stay in your boat and dump into the next lake.
• Dry, Leave everything in the sun for five days. If you can't wait five days, use a pressure washer with hot water, 60°C minimum. The heat kills larvae and adults.

Bait Management Matters

Never release live bait into the water. That goldfish or fathead minnow from the bait shop might carry diseases or parasites that native fish can't fight. Or it might be an invasive species itself.

Put unused bait in the trash. Not the water. Not on the ground. The trash.

Same goes for aquarium fish and plants. That pleco you're tired of? Don't flush it. Don't dump it in a pond. Kill it or rehome it. Brazilian waterweed and Eurasian watermilfoil are both sold for aquariums, and both are invasive in Quebec waters.

How to Report What You Find

The Quebec government tracks invasive species. If you catch a round goby, see a snakehead, or spot Eurasian watermilfoil in a new location, report it.

The government needs that information to track spread and decide where to focus control efforts. Your report matters.

Five Minutes at the Boat Launch

Invasive species don't spread themselves. They spread because people move them, a boat that doesn't get cleaned, bait that gets dumped, an aquarium emptied into a ditch. All of it adds up.

You can't fix the zebra mussel problem. They're here. They're not leaving. But you can stop them from getting into the next lake. You can keep round gobies out of the Rouge River. You can make sure Asian carp stay south of the border.

It takes five minutes at the boat launch. That's the difference between fishing and watching your favourite lake turn into something you don't recognize.

SUA Editorial Team Sub Urban Anglers, Montreal, QC

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