The Nottawasaga Valley Conservation Authority

Invasive Species

The Dirty Dozen

Invasive Species in the Nottawasaga Valley Watershed

Circle photo of Buckthorn

Invasive species are a significant threat to the Nottawasaga watershed. They are non-native plants and animals that aggressively take over habitat from native wildlife and plants. Invasive species usually spread with the help of humans, animals, wind and water. They prefer disturbed habitats, outcompete native species for resources, directly kill other species, introduce disease or hybridize with native species and take over their habitat which can adversely impact the environment, the economy, or society, including human health. Most of the time, invasive species don’t have natural predators.​​

Not only do invasive species threaten forests, wetlands, river and streams; they also impact our economy. It’s been estimated that the annual financial impact of invasive species across all sectors in the Great Lakes basin is nearly $30 million.

Within NVCA jurisdiction, Phragmites is a significant issue in many of our wetlands while garlic mustard threatens our hardwood forests. Even our provincial flower, the white trillium, is impacted by invasive species. 

Our swamps and forests are being threatened by the emerald ash borer which is causing mass mortality in our ash trees. Zebra and quagga mussels have impacted the entire Georgian Bay ecosystem. The round goby has colonized our shoreline and larger river systems.

Early detection and rapid response are essential for the control and/or eradication of invasive species in an area. If you find one of the invasive species listed above, please report the sighting to EDDmapS.

Other invasive species

NVCA developed a list of stewardship resources for landowners.

Please note that NVCA does not endorse or approve any of the products, services or opinions found on external sites.

Early Detection is Key

Early detection and rapid response is essential for the control and/or eradication of invasive species in an area. If you find one of the invasive species listed above, please report the sighting to EDDmapS Ontario at

Monitoring Invasive Species in the Watershed   

NVCA works with a number of partners to monitor invasive species in the watershed.

Below is a quick snapshot of NVCA invasive species work to date. Our long-standing partnership with the Ontario Federation of Anglers and Hunters (OFAH) summer student “hit squad” has facilitated this work.

NVCA has been involved with invasive species monitoring and/or control since 2005 – efforts to control invasive species are dependent on project funding and staff availability. Past and present projects include:

  • garlic mustard monitoring and removal (Tiffin Conservation Area 2005 – present)
  • garlic mustard monitoring (Bruce Trail report 2010)
  • garlic mustard removal (Petun Conservation Area – with Nature League 2011 –2015)
  • giant hogweed monitoring (watershed) and control (Collingwood, Wasaga Beach, Hockley, 2005 –2016)
  • wild parsnip monitoring (watershed) since 2009
  • Phragmites monitoring (Minesing Wetlands, Collingwood, Wasaga Beach) – since 2008; control project in Minesing Wetlands staring in 2011; technical steering committee participation (Wasaga Beach Provincial Park 2008-2011); partnership with Georgian Bay Forever and community groups to monitor and control Phragmites in West Collingwood (initiated Fall 2014)
  •  dog-strangling vine monitoring (Minesing Wetlands/Collingwood) since 2008; control projects starting in 2009 to present (in the Minesing Wetlands with Nature Conservancy Canada and County of Simcoe)
  • involvement with the County of Simcoe’s Emerald Ash Borer monitoring program
  • ongoing, incidental species monitoring

Invasive Species on Private Property

NVCA does not offer a service to remove invasive species on private property.  If you are looking for tips on dealing with invasive species on your property, see our fact sheets (above) or visit Ontario’s Invading Species Awareness Program.

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