Nature Conservancy of Canada
The Nature Conservancy of Canada (NCC) hopes people are enjoying the outdoors and connecting with nature this summer, but at the same time is encouraging them to help control the spread of invasive species.
The not-for-profit, private land conservation group is highlighting 10 invasive species that can be spread as a result of people going about their summer outdoor recreation. Activities such as camping, hiking, biking, fishing, boating, horseback riding and driving ATVs can unintentionally spread invasive species into our rivers, streams and forests.
Dan Kraus, Senior Conservation Biologist, Nature Conservancy of Canada, says: “Many invasive species have few natural predators to control them. Once they get into ecosystems, they’re often able to spread and out-compete our native plants and animals for space, water, food and other resources.”
They range from emerald ash borer beetle spread by moving firewood, spotted knapweed plant, which is spread through hiking and camping, to the Eurasian milfoil, which is spread by boating.
“Many invasive species have few natural predators to control them. Once they get into ecosystems, they’re often able to spread and out-compete our native plants and animals for space, water, food and other resources,” said Dan. “People may unknowingly be contributing to the spread of invasive species when they are enjoying the outdoors through their recreational activities. That’s why it’s important to share information and these steps so that people can minimize the spread of these invasive species to new areas in Canada.”
Here some of the invasive species spread through summer recreational activities:
Spotted knapweed: This aggressive invasive plant invades prairies, meadows and open woods. It can take over these habitats and reduce the number and diversity of native plants and animals. Each plant produces thousands of seeds that can be spread when they adhere to ATVs, horses, bikes, hiking boots and camping equipment.
Garlic mustard: This biennial plant is rapidly spreading across Canada, into forests and woodlands. It can form dense stands that exclude native plants, and can impact forest regeneration. Garlic mustard can be spread when the small seeds adhere to boots and clothing.
Eurasian milfoil: Known as the “zombie plant,” this aquatic weed grows quickly in the spring, forming a thick mass of tangled stems under water. These stems get caught in boat propellers and rudders and reduce native aquatic plants and impact fish habitat. It is primarily spread when boats are moved by trailer between lakes.
Zebra and quagga mussels: These small freshwater mussels have been spreading across North America. They can completely cover the bottom of lakes, impacting fishes, native mussels and water quality. They are spread when they attach to boat hulls, trailers and motors that are moved between lakes.
Emerald ash borer: This non-native invasive beetle has decimated tens of millions of ash trees and continues to spread rapidly. It can quickly kill large areas of ash trees, impacting forests, areas along streams and rivers and urban forests. It has spread to some areas through people moving firewood that has been cut from infected ash trees.
Spiny waterflea: This small freshwater crustacean feeds on zooplankton in lakes. Spiny waterflea can alter the food chain and impact native fish populations. Large numbers of spiny waterfleas form a jelly-like mass that clogs fishing gear and other equipment. It is spread by water from infected boats or when bait buckets are moved between lakes.
European and Asian earthworms: Many people are surprised to hear that most of the earthworms they encounter are non-native and invasive, including the “night crawler” often found in gardens and used for bait. Invasive earthworms damage forests, as they change the soil chemistry and structure. Earthworms can be introduced to forests by anglers dumping their leftover bait on land or in the water, and vehicles can transport earthworms or cocoons in their tire treads.
Domestic cats: Domestic cats can have a significant impact on populations of migratory birds, reptiles and small mammals, and are considered one of the world’s 100 most invasive species.
Cats that are brought to cottages and camps can kill birds and other wildlife of conservation concern and should be kept indoors, or on a leash outside.
For more information, including species profiles and tips on how you can help, visit NCC’s Invasive Species Gallery. www.natureconservancy.ca/en/what-we-do/resource-centre/invasive-species.