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Invasive Species

Web photo loosestife Lynde Shores

Conservation Authorities battle a number of invasive species which pose a growing threat to Ontario’s economy and native biodiversity. Invasive species damage important natural ecosystems such as wetlands, forest, lakes, rivers and streams, as well as threaten agricultural practices, infrastructure, tourism, fisheries, and water quality and quantity.

Purple loosestrife, garlic mustard, buckthorns, emerald ash borer, zebra mussels, dog strangling vine, reed canary grass (Phragmites), and round goby are a few of the invasive species that Conservation Authorities target with various local programs and initiatives across Ontario.

Monitoring the distribution of invasive species is important for controlling their spread and identifying areas of concern.

Conservation Authorities currently address invasive species through a wide variety of means:

  • watershed plans
  • habitat restoration and rehabilitation
  • forest management, tree and shrub planting
  • natural heritage strategies / invasive species strategies
  • water quality and quantity programs
  • natural lands management
  • community outreach and education
  • monitoring and reporting
  • technical advice

A total of 15 Conservation Authorities are members of the Ontario Invading Species Awareness Program.

Cost of Invasive Species

Source: Ontario Invasive Species Strategic Plan 2012

$75-91 million - total impact of zebra mussels in Ontario (Marbek 2010)

$400,000 - 450,000 spent by the City of Windsor for activated charcoal treatment to eliminate the taste and odour problems from municipal water supplies caused by zebra mussels upstream of the city’s water intake

$37 million in replacement trees to cut and replace Toronto’s city-owned trees killed by emerald ash bore over five years

$30 million spent by the Canadian Food Inspection Agency to slow the spread of the beetle

Conservation Authorities and Invasive Species Information

Some Conservation Authorities provide website resources aimed at specific invasive species found in their watersheds and provide actions that people can take.

Web photo Lakehead loosestrife cleanup