The spongy moth is an invasive moth originally from Europe. There have been sightings of spongy moths in Vancouver, Squamish and Whistler. As its egg masses are laid on firewood, tires, and trailers, this species spreads easily with the aid of humans.
This year, the Government of B.C. released and completed its 2024 spongy moth eradication program. Earlier this summer, it treated 13 areas in B.C. for spongy moth, in the hopes of eradicating this species from the province. You can read more about what the Government of B.C. has been doing here.
How do I identify spongy moths?
The appearance of spongy moths varies depending on their sex. Female moths are creamy-white with a 55 – 70 mm wingspan. Male moths are light to dark brown and much smaller than females, with a wingspan of 37 – 40 mm. Both sexes have pectinate antennae (which means their antennae look like a comb) and crescent-shaped markings on the front of their wings.
Reasons for concern
Spongy moth poses many threats to our region. Since it has no natural control methods (such as natural predators, for example), this species can reproduce prolifically. Each spongy moth egg mass contains 100 – 1000 eggs, and once hatched, its larvae feed on over 500 species of trees and shrubs. Spongy moth larvae can completely defoliate and even kill trees.
This species also attacks fruit trees and blueberry plants, which can affect crops.
Spongy moth egg masses. Ferenc Lakatos, University of Sopron, Bugwood.org
What can you do?
- Buy Local, Burn Local. Do not move firewood from one location to another, as egg masses may accidentally be transferred with the wood.
- Keep an eye out for egg masses, larvae, caterpillars or moths. You can destroy them by soaking them in hot soapy water for two days and placing them into household garbage.
- If you are travelling, check your camper, trailer or RV before and throughout the trip.
- Report any sightings of spongy moth.