Sweet clover can take over naturally disturbed habitats.  Pictured is yellow sweet clover.  The closely related white sweet clover is found in many places in the NWT.  Photo:  Zeynel Cebeci / Wikimedia Commons:  CC BY-SA 4.0 Sweet clover can take over naturally disturbed habitats. Pictured is yellow sweet clover. The closely related white sweet clover is found in many places in the NWT. Photo: Zeynel Cebeci / Wikimedia Commons: CC BY-SA 4.0

Talking about Pests, Pathogens and Invasive Species: A Symposium

The NWT’s first Symposium on Pests, Pathogens and Invasive Species took place in Yellowknife on April 9-13, 2018.  About 100 people took part, coming from other parts of Canada and as far afield as the U.S. to present on their research, experiences and lessons learned, and to share ideas in a talking circle.  While pests, pathogens and invasive species are emerging issues in the NWT, they are not new to other places. 

WRRB Board Member and Wildlife Biologist (Biodiversity), GNWT, Dr. Suzanne Carrière was one of the presenters and an organizer of the Symposium.  “This was a great networking opportunity,” she said, “and the NWT will benefit from the experience of other jurisdictions that have been dealing with these issues longer.”

An important focus of the conference was to discuss setting up a network or council to help prevent the spread, help control, monitor, and take action on pests, pathogens, and invasive species in the NWT.    

A pest is a plant or animal which is troublesome or causes harm to plants or animals, humans or human concerns including crops, livestock, and forestry. A pathogen is something that is infectious, such as a virus or bacteria, which causes a disease. Invasive species are among Canada’s greatest threats to the survival of wild animal and plant life. 

What are invasive species?

What makes a species invasive?  An Invasive species is a plant, fungus or animal species that is not native to an area but arrived, often accidently, from elsewhere. Not all species introduced from other places are invasive and harmful.  A species is considered invasive when it poses a threat to native ecosystems, habitats and species.  Invasive species tend to spread and can compete with native plants and animals, crowding them out, reducing biodiversity (the variety of living things in a place), and changing natural habitats.  Many lack natural predators in their new environment to keep their populations in check and can spread faster, giving them a competitive edge over native species.  Not only do these invaders have potential impacts on the ecology of their introduced ranges, but also on the economy or society. 

In rare cases, a native species can become invasive if the balance of the ecosystem is changed, like in the case of climate change.  This allows the native species to expand its native range and invade new environments.  Suzanne described that “as the environment is changing, some of the native species are acting strangely and are being invasive.” The mountain pine beetle, native to western Canada, is an example of a species that has expanded beyond its traditional range and its main host, lodgepole pine, into the jack pine dominated Canadian Shield further north east.  “All species want to increase their numbers,” Suzanne explained.  “If you release the prevention mechanism, weather for example, they evolve.  Some of the changes these beetles have evolved are to attack jack pine.” 

Are pests, pathogens and invasive Species a concern in the NWT?

Our northern climate prevents many non-native (also known as “exotic” or “alien”) species from establishing themselves in NWT’s ecosystems.  However, with climate change and other factors, this may be changing. Changes in the northern environment may favour the advance of alien species into our ecosystems . If the climate gets warmer, more species that previously could not survive here may thrive.

Examples of invasive species introduced to the NWT to date include sweet clovers (a type of plant) and amber-marked birch miners (a type of insect).  “Other species are expanding their ranges –coyotes, magpies, bison, and muskox, for example—but may not be invasive,” Suzanne said.  In her presentation, she reported on the findings from the first 10 years of the NWT Invasive Alien Species Program.  Those findings estimate that of the 5,257 species tracked so far in the NWT, 3.2% are alien (introduced) and so far, only a few of these alien species are deemed high-medium invasive.  Most are transported to the NWT unintentionally or have expanded naturally north. 

As well, there are many natural disturbances in the North, such as wildfires.  “Disturbed areas are more prone to invasions,” Suzanne said.  “Some of these species are not invasive down south but are invasive in the North, a different ecosystem.”

What were some of the topics presented at the Symposium?

  • NWT “pathway” analysis to determine how species are likely to arrive in the NWT and spread
  • Forest insects, pests and pathogens in the NWT
  • Observations of changing species interactions in the Inuvialuit Settlement Region, NWT
  • Co-managing beavers in the Mackenzie Delta
  • Exotic plants in Alaska and community efforts to control them
  • NWT Community Bat Program:  Outreach and monitoring for white-nose syndrome (a disease caused by an invasive fungus resulting in high bat mortality in eastern North America.)
  • Monitoring for the arrival of white-nose syndrome in Alaska
  • Chronic Wasting Disease (a disease that can be found in deer) and implications for caribou and other northern ungulates
  • Invasion and range expansion of lungworms (parasites) in caribou and muskoxen in the changing Arctic, and investigating the impacts of climate change on the ongoing range expansion
  • Investigating a bacterium that has been detected in muskoxen and caribou

Forming a Council in the NWT

A council can be a place where people can learn about this issue and what they can do to help to halt the introduction and spread of pests, pathogens, and invasive species in the NWT.

"Focus on prevention, keep the long-term in mind, make it accessible, and provide information for prevention and positive behaviour."

-Talking circle comment on a vision for the council

“We have to be up-to-date on the fast-changing knowledge base on this issue,” Suzanne said. “A council can sift through all the information out there and find the most accurate, reliable, and relevant information.”  People will be able to go to the council for advice on choosing the right, non-invasive plants for their gardens, for example.  Invasive plants may bring undesirable insects and diseases along with them, could be toxic and harmful to wildlife, change or displace habitat, or have other negative impacts. 

“It’s important to have a body with lots of people with lots of knowledge. The idea is to have a core group with many resource people to look for solutions and have success." -  Suzanne Carrière

Prevention and early detection are key to minimizing these threats to NWT ecosystems.  Once an undesirable non-native species is established, it can be costly to control and manage it. The council will be able to help people learn to identify introduced species and report their sightings.  “If you see something new out there, ask an elder and pass the information along,” Suzanne said.

The council will also provide education on ways to prevent the spread of these species.  Insects, plants and diseases can be transported from one place to another by means of clothing, equipment, boats, firewood and other things. Cleaning off all plants, organisms and mud from your boat and equipment (e.g. boots, fishing gear, etc) is one preventative measure.  Draining all water before launching your boat into another body of water is another. 

The Symposium gave participants a good head start on setting up a council and how it should work.  “We have an idea for a mandate, and the composition of the council and its governance.  We’ve also identified short-term actions and three-year actions,” Suzanne said.  Those ideas will be presented to the NWT Agricultural Strategy, GNWT. 

Fact Box -Where to Report Non-native Species

  • NWT residents can help determine the current distribution of alien species in the NWT by reporting their presence to ENR offices.
  • Help stop the spread of invasive plants and insects in the NWT. Report “out-of-place” species by contacting NWTSOER@gov.nt.ca or NWTBUGS@gov.nt.ca

Fact Box – Introduced Species and Ecosystems

  • Ecosystems are created and maintained by a perfect balance of many factors that exist and interact together, such as climate, food webs, a diversity of species, and soils.  Each species occupies its own unique niche within the environment. 
  • An introduced or “exotic” species has been introduced into an ecosystem outside of its native range.  Many of these species have little impact on the native environment, and often disappear as soon as they arrive, or establish themselves within the new ecosystem without disturbing the local balance. 
  • However, every so often a species is introduced into a new environment where the conditions are favourable for establishment, and the “exotic” species could become invasive.