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Posted on Sept. 5, 2024
The aquatic invasive plant, hydrilla, has been detected for the first time in Ontario and Canada in the West Cell at Hillman Marsh Conservation Area located in Leamington, Ontario.
Hydrilla (Hydrilla verticillata) can grow up to 2.5 centimeters per day and to lengths of 7.5 meters. This rapid growing invasive species can choke out native species and clog water intake pipes, boat motors and impede other recreational activities like swimming and paddling. Hydrilla is a prohibited invasive species under Ontario’s Invasive Species Act 2015.
Essex Region Conservation Authority (ERCA) is working closely with the Ministry of Natural Resources, the Invasive Species Centre, the Ontario Federation of Anglers and Hunters and many other partners to evaluate the extent of the infestation, contain the spread, and develop plans to control this invasive species. To date, surveys have shown the infestation to be limited to the contained wetland area of the West Cell of Hillman Marsh that is not directly connected to Lake Erie.
In a pro-active effort to contain the spread of this invasive plant, ERCA will be immediately closing the West Cell of Hillman Marsh, including the trail and boardwalk, to boating, walking and hunting. Hydrilla is easily spread when boat propellers, kayaks, canoes, trailers, fishing and hunting gear, pets or people inadvertently carry attached plant fragments to new areas. The Conservation Authority is asking the public for assistance in refraining from accessing this area.
“Ontario recognizes the importance of the prevention, early detection and management of invasive species that pose a threat to Ontario’s native species and ecosystems. If left unchecked, hydrilla – an aggressive aquatic plant – has the potential to severely impact navigation, recreation, and aquatic life,” said Graydon Smith, Minister of Natural Resources. “That’s why we’re working diligently with our partners to develop plans for its control.”
“The detection of this highly aggressive water plant is alarming,” says Kevin Money, Director of Conservation Services, ERCA. “Most concerning is its ability to significantly disrupt, alter and outcompete the natural ecosystem. We take its detection within our wetland with the utmost seriousness and are proactively taking all steps we can to contain it, including, unfortunately, halting recreational activities within the cell and its surrounding area.”
“This is the first time that hydrilla has been found in Ontario and Canada, so we are encouraging people to learn how to identify hydrilla, report it and clean, drain, dry your boat to help prevent the spread of this serious invasive plant from Hillman Marsh” says Sydney Currier, Aquatic Invasive Species Coordinator, Invasive Species Centre.
“When my team from the Waterloo Wetland Lab found an unusual underwater plant, we suspected that it could be hydrilla,” says Dr. Rebecca Rooney, Associate Professor in the Department of Biology at the University of Waterloo and Director of the Waterloo Wetland Lab. “Because hydrilla is so easily spread, we must be vigilant with control measures and thoroughly decontaminate any equipment used in the marsh, above and beyond typical cleaning procedures.”
What Community Members Can Do
People can help prevent the further spread of hydrilla by:
- Learning how to recognise hydrilla by visiting the Invasive Species Centre Hydrilla Species Profile. MNR Profile, Ontario’s Invading Species Awareness Program Profile
- Reporting sightings of hydrilla through the EDDMapS or iNaturalist websites or mobile device applications or by calling the Invading Species Hotline 1 (800) 563-7711. A good report includes an accurate location of the sighting and photos.
- Clean, drain, and dry your watercraft, including motorized boats, canoes, and kayaks. It’s the law in Ontario.