Invasive Species | Forest Pests
Spongy Moth
Spongy Moth
(Lymantria dispar dispar)
French common name: Spongieuse
In July 2021, the Entomological Society of America removed “Gypsy Moth” as a recognized common name in its Common Names of Insects and Related Organisms List. As of March 2022, “Spongy Moth” has been formally adopted as the new common name for this moth species, which is derived from the French common name used to describe the sponge-like egg masses of this moth species.
Description:
The Spongy Moth is native to Europe, and has become established throughout New Brunswick, Nova Scotia, PEI, and other Canadian provinces and northeastern United States. Adult moths produce large amounts of eggs that persist through winter and create caterpillars that damage a wide variety of hard and softwood tree species. Many municipalities throughout New Brunswick and Canada are experiencing an increase in the impacts of Spongy moth as their population experiences a boom.
Problem:
Spongy moths produce many eggs and caterpillars that can defoliate trees throughout the late spring and early summer, impacting the trees overall health and ability to recover the following year. Spongy moth invasions can lead to large scale tree die off and impacts to forest health as some trees may be unable to produce additional leaves throughout the growing season. Spongy moths and caterpillars can outcompete native insects for habitat and resources, impacting biodiversity.
Species identification:
Spongy Moth eggs: Eggs appear as a tan/yellow colour fuzzy mass, approximately 2-4 cm across that female moths lay on tree bark and other outdoor items like furniture and equipment.
Spongy Moth females lay between 500-1000 eggs in tree bark crevices in mid to late summer, and eggs hatch the following spring (April)Spongy Moth caterpillar: The larval form of Spongy moth is a dark coloured caterpillar, approximately 6 cm in length, that is covered in spikey hairs and pairs of red and blue dots that run down their back.
Caterpillars pupate in a dark brown, kidney shaped hard shell that hangs from tree bark and other hard surfaces.
Spongy Moth adults: Winged moths that appear in mid-summer (June-July), males are a tan/brown colour, with feathered antennae and wings capable of flight while females are a lighter beige/white colour and cannot fly.
How it’s spread:
Female moths lay eggs on a variety of hard surfaces including outdoor chairs, camping equipment, car tires, and other items stored outdoors. It’s important when storing equipment outdoors or moving items between areas to check for Spongy moth eggs and Play, Clean, Go. Clean off all equipment, the bottom of your shoes, and other materials to ensure you don’t transport Spongy Moth eggs and other invasive forest pests.