You could almost set your watch by it.
Since 2013, when zebra mussels were first detected in Lake Winnipeg, new sightings of the invasive species in our lakes and on our shorelines have become a regular occurrence.
And while the ubiquitous videos of their shells collecting on the shores of Lake Winnipeg that we have all seen doing the rounds on social media channels reveal how much of a plain nuisance they can be, we should also remember that zebra mussels can have very negative impacts on the freshwater ecosystems that they invade.
These range from reducing nearshore water quality and affecting fish populations to clogging water inlets and fouling watercraft.
Just this month, while conducting standard sampling of Lake Manitoba, the province discovered zebra mussel veligers, or young zebra mussels — which, as was the case for Lake Winnipeg, likely means we can expect to see adult mussels there within a few years.
The provincial response was duly swift and comprehensive. It involved reaching out to local communities to inform them of the observation, while mandating compulsory decontamination of watercraft and water-related equipment when being transferred from Lake Manitoba to other bodies of water.
These actions on the part of the provincial government, in addition to continued public education campaigns, are completely necessary to stem the tide of zebra mussels in Manitoba’s water. But these are steps towards mitigation, and therefore only one side of the story.
The ever-intensifying impacts of climate change warming lakes here and across the globe will also likely enhance conditions for zebra mussels to continue to flourish in lakes suitable for their establishment.
And while mitigation efforts are critical and must be built up to prevent further spread, they don’t do much for bodies of water that are already infested.
The fact that zebra mussels have continued to abound in Manitoba’s freshwater bodies since 2013, despite enacting preventive measures, and are established, or being established, in our largest and most economically productive lakes suggests that we will have to change our management of these systems — with zebra mussels proving a permanent yet inconvenient addition.
What does this mean in practical terms?
First, our habits as users of these water bodies needs to adapt to the increased risk of spread. Boat inspection and decontamination stations are crucial, but we also all need to take more personal responsibility to protect these shared resources with self-inspections — supported by clear and accurate guidelines for lake users and local residents.
Second, we need to beef up the science so we can manage waterbodies that have already been infested more effectively.
We still need to understand better how zebra mussels are integrating into the specific food webs and ecosystems in which they are establishing and how they can impact water quality and fisheries. This understanding needs to be specific to Manitoba’s waters so we can adapt and manage our lakes as a whole more effectively.
This means more monitoring and a better overall co-ordination of research efforts in all pockets of the province to ensure that the results are immediately built into effective policy to tackle the scourge of zebra mussels.
And, of course, this requires greater investment to support organizations tasked with protecting water quality and fisheries. If we are to understand and manage the impacts of zebra mussels, we need to resource the problem appropriately.
But while an initial investment will likely need to be made, the outcome of better management of Manitoba’s proverbial 100,000 lakes? Well, that’s definitely worth the cost.
Michael Rennie is research fellow, IISD Experimental Lakes Area and associate professor at Lakehead University.