Invasive Species

Environmental impacts:

• Degrading or eliminating habitat
• Reducing native species populations by out-competing them for resources
• Reducing biodiversity
• Introducing foreign diseases or parasites into an ecosystem

Economic impacts:

• Reducing the yield of agricultural producers
• Causing trade restrictions or barriers
• Increasing public health care costs
• Causing high pest control costs
• Increasing financial burdens caused by control measures
• Nnegatively affecting property values
• Clogging or damaging irrigation equipment
• Impacting tourism

Societal:

• Causing health problems or physical discomfort such as allergies
• Reducing recreation opportunities
• Reducing the aesthetics of the landscape
• Creating foul odours
• Displacing desired species of traditional value

• Transport on equipment: Soil on construction equipment often transports invasive seeds into new areas. Aquatic invasive species can be transported on boating and fishing equipment. Airplanes, trucks and ships that carry goods and materials can move invasive species from around the world to Alberta.
• Nursery plants: Plants sold in garden centres can be invasive themselves, have other hitch-hiking plants, or have insects on the plant or in the accompanying soil. Invasive plants have also been found in wildflower seed packages.
• Hitch-hiking on goods: Goods such as commercial seed, hay, forest products with bark, and solid-wood packing material such as crates and pallets are materials often used by hitch-hiking invasive species to enter an area.

Invasive alien species include plants, mammals, fish, reptiles, amphibians, shellfish, insects, fungi and bacteria.

Aquatic

• Rock snot algae or “Didymo” (short for Didymosphenia geminata) attaches itself to rocks, plants and other submerged surfaces in rivers and streams. The gooey algae grow rapidly, covering the stream bed and attracting aquatic insects, which burrow themselves deep into the algae. This reduces the quality of spawning habitat and the amount of food available to fish, which also affects their ability to spawn.
• Goldfish have been released into Alberta’s waters by the public. They occur, and have been known to reproduce, in municipal garden ponds and have been found in natural waters. This member of the carp family poses a significant ecological risk. No aquarium plants or animals should be released into waterways.
• Zebra and quagga mussels have moved rapidly across North America and now are found in states close to the Alberta border. These mussels have significant impacts on aquatic ecosystems and cause extensive fouling problems on irrigation and water treatment infrastructure.

Land Plants

• Oxeye daisy is a classic white daisy that invades pastures and natural areas, reducing plant species diversity and hay or forage production. It is unpalatable for livestock or wildlife, giving it a competitive advantage and can give an off-flavour to milk if cattle graze on it.
• Yellow clematis is a spreading vine plant with yellow, pendant flowers. It is aggressive once established, displacing native flora and increasing fire hazard. Yellow clematis is moving into mountain parks.
• Himalayan balsam is a garden ornamental introduced in the 19th century. It grows rapidly, out competes native vegetation and often dominates vegetation stands in riparian area.

Other

• Wild boar were brought to Alberta in the 1990s as a specialty livestock, but some have escaped from farms and have adapted well to Alberta’s rough terrain and cold winters. They eat crops and dig large holes on farmland.
• Fusarium Head Blight (FHB) is a fungal disease of cereal crops that affects kernel development. This disease spreads easily via wind and through transportation of infected crop residue or seeds. Fusarium has been found in the irrigated regions of southern Alberta and has potential to spread to all other parts of the province.

Examples of invasive alien species:

• Alberta Invasive Plants Council Weed Wise Brochure
• Costs & Threats of Invasive Alien Species to Alberta’s Natural Resources  – Mar 2004 (122 pages)
• Invasive Aquatic Species in Alberta  – 2007 (1 page)