What you should know
Not every introduced animal is invasive
Yukon is also home to introduced birds, mammals, fish and other organisms. Being non-native does not automatically make a species invasive. This page focuses on animals for which there is stronger evidence of ecological concern in Yukon and practical action you can take to help.
How invasive animals spread
People accidentally move small animals much farther than they could travel on their own. Earthworms and their cocoons can be transported in bait, soil, compost and garden materials. Other introduced organisms may escape or be intentionally released.
Our watchlist
Seven-spotted lady beetle
Coccinella septempunctata
Status: Present in Yukon
This introduced lady beetle has seven black spots on its red or orange wing covers. It is known from several locations in Yukon and has been found spreading into more remote areas. It can compete with native lady beetles and may also prey on their eggs or larvae.
Octagonal-tail worm
Dendrobaena octaedra
Status: Present in Yukon
Several introduced earthworm species have been recorded in Yukon. The octagonal-tail worm is widespread and is currently rated by the Yukon Conservation Data Centre as having medium invasiveness.
Introduced earthworms can change the layers of leaves and organic material on forest floors, altering soil conditions and affecting other organisms. Impacts vary considerably between earthworm species.
Multi-coloured Asian lady beetle
Harmonia axyridis
Status: Watch for it, Yukon status uncertain
This highly invasive lady beetle has spread through much of southern Canada, where it can compete with native lady beetles. Its colour and number of spots vary widely; a dark M-shaped marking behind the head can help with identification.
The Yukon Conservation Data Centre currently rates this species as highly invasive, but its current presence in Yukon remains uncertain. Photograph suspected sightings rather than relying on spot count alone.
What you can do
1
Never dump unused bait worms on the ground or into the water. Take them home or put them in the garbage.
2
Don’t release purchased insects or other animals into the wild.
3
Keep garden soil, compost and plants out of natural areas, and avoid moving soil unnecessarily between sites.
4
Watch for unusual species. Take a clear photo and record the exact location rather than moving the animal.
Invasive Animals
Yukon has relatively few established invasive animals compared with invasive plants, and keeping it that way matters.
An invasive animal is a non-native species that can spread and cause ecological, economic or other harm.
Many introduced animals and insects are not invasive, so this page focuses on the small number of species that Yukon evidence identifies as higher concerns.
Sources
Information on this page was reviewed in September 2026 using current Yukon and Canadian sources, including, but not limited to:
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Yukon Conservation Data Centre — Exotic Species Data (July 17, 2026): Used to identify introduced animals known or reported in Yukon and to inform the Yukon status and invasiveness information shown on this page. The Yukon CDC is the Government of Yukon’s central source for species information.
Yukon Conservation Data Centre species data
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Government of Yukon — State of the Environment Interim Report 2025: Used for the broader picture of introduced species in Yukon and the Yukon CDC’s current approach to invasiveness rankings. The report includes information available to the end of 2024.
Yukon State of the Environment Interim Report 2025
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Committee on the Status of Endangered Wildlife in Canada (COSEWIC) — Transverse Lady Beetle: Used to describe possible impacts of introduced lady beetles on native lady beetles, including the Seven-spotted and Multicoloured Asian Lady Beetles.
COSEWIC Transverse Lady Beetle assessment
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Natural Resources Canada — Invasive Earthworms and Boreal Forests: Used to describe how introduced earthworms can alter soils and ecological processes in northern forests, and why preventing their spread is important.
Earthworms, a threat to Canada’s boreal forest?
Species distributions and status can change as new observations become available. YISC will periodically update this page as Yukon knowledge improves.