Invasive Species
Invading species are one of the greatest threats to the biodiversity of Ontario’s waters, wetlands and woodlands. Originating from other regions of the world, and in the absence of their natural predators or controls, invading species can have devastating effects on native species, habitats and ecosystems.
Invading species extremely adaptable and have high reproduction rates enabling them to spread. Unchecked, these invaders will outcompete native fish and wildlife and unbalance natural ecosystems. The Rusty Crayfish and Spiney Water Flea are now found in Lake of the Woods and it’s become hard to find our natural Green Grey Crayfish as their population has already been negatively impacted by the competition.
To identify the Rusty Crayfish, look for the rusty ‘fingerprints’ on either side of their body.
Invading species are introduced to Ontario waters through a variety of pathways such as ballast water from foreign shipping, aquarium & horticultural trades, live food fish trades, unauthorized fish introduction’s and/or transfers. These species are being further spread into our inland lakes through recreational activities such as boating, angling, and through the release of live bait.
Invasive Species are a threat to the natural bio-diversity of aquatic eco-systems and to species at risk. The reasons for their ability to alter a system are:
- They have no natural predators.
- They are highly adaptable
- They reproduce quickly
- They thrive in disturbed systems
- They out compete native species for food and habitat
In 1992 the Ontario Federation of Anglers and Hunters, in partnership with the Ontario Ministry of Natural Resources, established The Invading Species Awareness Program. Our objectives are to:
- Raise public awareness of invasive species and encourage their participation in preventing their spread.
- Monitor and track the spread of invading species in Ontario waters through citizen reports to the Invading Species Hotline and the Invading Species Awareness Program
- Conduct research on the impacts and control of invasive species
Invasive Plants in Northwestern Ontario
Purple Loosestrife
Purple loosestrife originated in Europe and was accidentally introduced into North America in the early 1800s as a contaminant in ship ballast and as a medical herb. It has taken many years for this weed to impact our area, but it is now present in many regions. Also known as the beautiful killer, marsh monster and exotic invader, purple loosestrife establishes itself in a variety of urban and rural wetland habitats.
Purple Loosestrife greatly reduces biodiversity in the wetland, dominate and eliminate many valuable plant species. The displacement of native vegetation by purple loosestrife reduces the value of wetlands and has far reaching ecological implications, many of which are still unknown.
Flowering Rush
Found in many aquatic areas in southern Manitoba and Northwestern Ontario, Flowering Rush is a perennial with grass-like leaves similar to bulrushes. Along with Purple Loosestrife, it is regarded as one of five invasive alien plants having a major ecological impact on natural ecosystems in Canada and considered a high priority species for eradication in parts of Ontario.
Flowering rush invades aquatic and wetland areas including streams, rivers, lakes, stormwater retention ponds, marshes and gravel pits as well as road side ditches. It can displace native vegetation reducing the overall biological diversity of an ecosystem by restricting light and nutrients to other submerged plants.
