A year ago in Leamington, Ontario, one of North America's most invasive aquatic species was discovered for the first time in Canada. Hydrilla verticillata (hydrilla) was found in Hillman Marsh near Point Pelee National Park by Biology Professor Dr. Rebecca Rooney and her research team during a wetland survey. Now, her Waterloo Wetland Laboratory at the University of Waterloo is leading the efforts to eradicate the plant before it spreads across Ontario.
Critical to this research is Master of Science in Biology student Kayla Martin, who is monitoring the marsh's native plants, water quality and benthic invertebrates (the small organisms that live at the bottom of lakes and rivers) to understand the impacts hydrilla is having on the ecosystem. This work is part of the University of Waterloo's effort to safeguard ecosystems and ensure a sustainable future.
Hydrilla is an aquatic plant that grows in extremely dense mats, so dense that you can barely see the water between the plants. These mats negatively impact the water quality, making it difficult for native plants to grow and thrive. The Essex Region Conservation Authority (ERCA) has hired licensed applicators to apply herbicide treatments to the infected area to eradicate it, and the Waterloo Wetland Lab is monitoring the effectiveness of those treatments. The goal is to remove it before it can spread, which could take several years.
"Invasive hydrilla can throw an entire ecosystem off balance," says Martin. "If there aren't invertebrates, fish don't have food, which then impacts the animals that rely on fish. It can also reduce the presence of native plants that animals depend on."
The good news is that Hillman Marsh has two separate wetland cells, both isolated from Lake Erie. Hydrilla is present in the west cell, while the east cell remains free of the invasive plant, giving Martin a comparison to study its effects. The west cell is hydrologically controlled, allowing the ERCA to reduce the risk of hydrilla spreading.
On the left: Young hydrilla plant. On the right: Mature hydrilla plant.
"In addition to closing all activities in and around the West Cell, ERCA continues to engage in significant outreach and education in an effort to stop the spread of invasive hydrilla," said Kevin Money, ERCA's Director of Conservation Services. "We're very grateful to the many partners who continue to collaborate in this important effort."
Come spring, Martin will study how effective the different treatments applied to the hydrilla have been. The lab's goal is to develop a reliable treatment plan so that if the invasive plant appears elsewhere, there is a proven method to remove it.
Martin's interest in aquatic ecology comes from her love for the outdoors. Growing up, she always volunteered for environmental cleanups and tree planting projects at school. In her spare time, she is an avid scuba diver and has seen first-hand the damage invasive species can cause, which makes this project even more personal. When deciding where to pursue her master's, the University of Waterloo's reputation in water science made it an easy choice.
"I am proud to be a part of a group of Waterloo researchers contributing to a sustainable future," says Martin. "I am thrilled to be working on a project that will have a lasting impact on the environment."
With hydrilla threatening to spread across Ontario, that impact could not be more urgent, and the Faculty of Science at the University of Waterloo is proud to be at the forefront of the fight to stop it.
