Understanding the Impact of Invasive Species

All photos by Tim Antill

Originally native to Eurasia, Russian thistle (Salsola kali) has become naturalized to the point of being considered commonplace across the Canadian prairies. More than just a noxious weed, Russian thistle is actually an invasive plant species that competes with Canada’s native plants for valuable space and resources, often to the detriment of native ecosystems and local wildlife. With a $7,500 grant from the Canadian Wildlife Federation, University of Alberta (U of A) MSc Candidate Tim Antill, along with U of A professor Dr. Anne Naeth, will be investigating the impact of Russian thistle on native ungulate habitat in montane grasslands.

Their research will focus on Jasper National Park, where large areas of Russian thistle have been observed encroaching on native montane grasslands. The areas of particular interest to Mr. Antill and Dr. Naeth are located within the Athabasca River valley, which provides important winter range habitat and grazing opportunities. Because of large populations of bighorn sheep, elk and other ungulates, the remaining native grassland is becoming increasingly overgrazed, which may be contributing to the growing establishment of the unpalatable Russian thistle. Compromised native montane grassland could be a detriment to local ungulate populations, as well as have a negative impact on local biodiversity.  

The conservation of Canada’s native species and spaces is an integral step in reducing habitat loss and protecting biodiversity. Mr. Antill and Dr. Naeth have outlined a number of objectives for their research that will greatly assist land and park managers throughout the province when dealing with invasive species and ungulate grazing. Their objectives include:

• evaluating how Russian thistle impacts the native plant community;
• assessing the role of wildlife grazing on Russian thistle establishment and persistence;
• determining the effectiveness of herbicide application and mechanical or manual removal on Russian thistle control and
• determining if native plant communities can recover and displace Russian thistle once grazing pressure is reduced.

Following the conclusion of their research in 2010, Mr. Antill and Dr. Naeth will be providing the results of their study through scientific journals as well as presentations and conferences to both academic and public audiences.

Want to learn more about the importance of native plants? Visit the Canadian Wildlife Federation’s National Wildlife Week website.