Invasive Zebra Mussels Seen Hitching on Quebec Lake Fish, Threats Possible Spread to Other Lakes

According to research, invasive zebra mussels in Quebec have been feeding on lake fish and could spread to other lakes.

Invasive Zebra Mussels

In North America, zebra mussels (Dreissena polymorpha) are among the most damaging aquatic invasive species.

These tiny mollusks, which originated in Russia and Ukraine, have spread throughout the world as a result of being frequently transported in ballast water, which is used to stabilize boats.

By clogging intake pipes and stealing nutrients from ecosystems, they have caused billions of dollars in damage to water treatment plants, fisheries, and other aquatic industries.

Now, researchers have found out that the invasive mussels have been hitching a ride on fish.

The discovery was made by researchers last year as they evaluated the fish communities in a southeast Quebec lake.

A lake chub (Couesius plumbeus), a type of minnow that is typically about 12 centimeters long, was discovered with a zebra mussel attached to it.

The discovery, which was published this month in Biological Invasions, marks the only instance in which a freshwater bivalve without larvae has been spotted attached to a fish.

The mollusk used byssal threads, and protein fibers they also use to cling to rocks, plants, and concrete to latch onto the helpless minnow.

Threats of Possible Spread

The finding is especially worrying because fish have high mobility without a way to get rid of these parasites.

Lake chub and related species are frequently transported from one river or lake to another body of water because anglers use them as bait.

The authors worry that although boaters and others who enjoy infested waters are advised to wash their watercraft, discard any water they may be carrying before moving to another body of water, and clean off any plant matter from their equipment, those who use baitfish are probably unaware that they may unintentionally be moving zebra mussels.

They contend that the finding indicates greater caution may be required to avoid the introduction of zebra mussels to new areas, Science reported.

Avoiding the Spread

The USGS tracks the zebra mussel's geographic range and investigates its biology and behavior.

The resulting knowledge is vital in aiding the creation of plans intended to stop and restrict the spread of the mussel.

Zebra mussels are not recommended for use as aquarium pets, food, or bait and should not be caught or transported.

USGS also recommends washing boats with warm, soapy water, if possible, to maintain good boat hygiene.

Live wells and buckets of bait should not be moved from one body of water to another; instead, whenever possible, empty them onto land and throw any remaining bait in the trash.

Similar to zebra mussels, bait fish are frequently non-native to that body of water.

In the 1980s, zebra mussels most likely entered the Great Lakes through ballast water that was dumped by big ships from Europe.

Zebra mussels have a variety of negative effects on ecosystems. They remove the algae that are necessary for native species to survive, and they attach to and disable native mussels.

Millions of dollars must also be spent by power plants to clean zebra mussels out of clogged water intakes.