Insect populations are in steep global decline and moths are no exception. It is estimated that there are over 160,000 species of moths worldwide and we put together some moth facts to show why this diverse group is an important part of ecosystems. Many of them take the pollination “night shift” and may play an important, but under-studied, role in food production and the survival of our native plants. They are also an important food source for birds, bats, other insects, and sometimes even mammals like bears. Habitat loss and climate change are amongst the significant threats to moth populations.
Moth Facts:
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- Moths live in almost every habitat – wetlands, grasslands, forests, even the tundra.
- The largest moth in Canada is the cecropia, a member of the giant silk moth family with a wingspan of up to 18 centimetres.
- Some species of moths migrate in the fall, others survive winter in a cocoon. There are a few species referred to as “winter moths,” which can survive winters in southern Canada in their adult form.
- Many moths are impressive mimics. For example, there are approximately 40 species of clearwing moths in Canada, many of which mimic bees, wasps, and even hummingbirds.
- There are micro moths that have wing spans of less than three millimetres. Canada has dozens of species of pygmy leafminer moths, which are so small their presence is often only known because of the distinctive tracks they make on leaves.
- Moths are masters at evading predators. While some have amazing camouflage, others have developed features to intimidate predators like eye marks. Tiger and hawk moths seem to have developed skills to dodge being eaten by bats, specifically by emitting ultrasonic clicks that throw off the echolocation system of bats.
Photo: Spragueia Leo (Common Spragueia)

Myth busting moth facts:
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- Some moths do not eat in their adult state and don’t even have a mouth – like the beautiful luna moth.
- Adult moths do not eat fabrics. Out of the approximately 5,000 species in Canada, only two have caterpillars which feed on fabric.
- Not all moths are attracted to the light, some are repelled by it (this is considered “positive” or “negative” phototaxis).
Photo: Actias luna

Get tips for identifying moths in the wild!
Moth enthusiast David Beadle shares his experiences photographing and observing moths across North America.
Invasive Species
While there has been a lot of coverage around the spongy moth (or LDD) being an invasive species, other species of moths are showing promise as being a solution in the fight against invasive plants like phragmites. Learn more about our research.
Moth Species at Risk
Moth species and populations have been under-studied in Canada. There are only 22 moths listed as species-at-risk in Canada, many of which are specialists to particular plants or habitats. For example, the soapweed (yucca) plant is threatened because it is only pollinated by the endangered yucca moth. Due to a lack of data and documentation, we are unsure of the true number of species of moths in Canada or the status of their populations. You can help scientists across the country learn more about moths by sharing your sightings on iNaturalist.
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Support conservation and help save moth populations
Habitat loss remains one of the biggest threats to moth populations. Your donation will help DUC conserve the natural areas these fascinating creatures need.