The Great Lakes and their connecting waterways hold more than 20% of the world’s surface water, but this vital system is under immense stress. Climate change, introduction of invasive species, habitat fragmentation and nutrient runoff from human processes all threaten the health and stability of these waters.
Home to more than 3,500 species of fish, birds, mammals, reptiles, plants, amphibians and insect’s, the Great Lakes rely on a delicate balance of resources and energy function. The intricate network of interactions amongst these species are the basis of a food web – disrupt one strand and it can have negative impacts throughout the whole ecosystem.
Dr. Kevin McCann, Dr. Joey Bernhardt and Dr. Carling Beig are all world-class experts in ecosystem research and faculty at the University of Guelph in the Department of Integrative Biology. These three deeply understand the importance of aquatic ecosystem balance, health and stability. Together, these researchers created the Centre for Ecosystem Management, dedicated to research on the threats against aquatic ecosystems, and how management systems can aid or undermine their resilience.
“The great thing about our work with Food from Thought is it has sparked specific findings, but it also sparked whole programs like the Centre for Ecosystem Management,” McCann explained. The CEM has since grown into a research program with many projects, with 7 post-doctoral fellows generating wide-ranging discoveries.
The Centre for Ecosystem Management provides the connection point for the researchers to work directly with industry, conservation groups and government authorities on research, policies and protection of the Great Lakes ecosystems.
“We do not do this theoretical work and have the research sit on a shelf,” McCann explains. “Rather we collaborate with industry professionals, other institutions, and policy makers to try and make real changes on how we manage our aquatic ecosystems.”
From Farms to Healthy Watershed Ecosystems
One example of how the Centre for Ecosystem Management is protecting the Great Lakes is the pressing issue of nutrient overload. To grow healthy crops and increase yields, farmers standardly blanket spray crops with fertilizers. Phosphorus, a key ingredient in fertilizers, can cause major downstream effects when in excess. This excess phosphorus fuels algal blooms, which depletes oxygen in the water and can kill other aquatic organisms.
The Center for Ecosystem Management aimed to measure exactly how much fertilizer runoff from farms affected the freshwater ecosystems in the surrounding landscapes. Studying fish in streams around fields, they found something concerning: the fish in the area ate fewer insects and materials like leaves that come from the land, instead, eating more varied food. This might not sound like a big deal, but this is a change from normal behaviour and changes the typical food web, leaving the ecosystem vulnerable to more stress.
But here is the twist – this shift only occurred when the farm was right next to the stream. If there were natural buffers like trees or plants along the edges (called riparian zones), the fish diets stayed more stable even if there was a lot of farming across the broader area. This suggests that preserving strips of natural vegetation right next to streams can help protect the way ecosystems work, even in heavily farmed regions.
This finding shows that preserving riparian zones can safeguard the natural balance of ecosystems, even in regions dominated by agriculture. It is exactly the type of evidence that the Center works to bring to policymakers and the public, advocating for practical solutions that balance food production with environmental health.
Beyond the Shoreline
The riparian zone study is just one example of the Centre’s applied research. Across projects, their goal is the same: to provide science that informs real-world decision-making and supports the long-term health of aquatic ecosystems.
The challenges facing aquatic ecosystems are complex, but solutions are within reach. By protecting the links between land and water, supporting biodiversity, and grounding policy in evidence, we can help ensure these waters remain vibrant for the species and people that depend on them.
Read more about the Centre for Ecosystem Management and McCann’s work on aquatic ecosystems are protecting the balance in the Great Lakes.
