Gypsy moths (Lymantria dispar) evolved in Europe and Asia. They were accidentally introduced to North America, near Boston, in 1868 or 1869. Since then the range of gypsy moths has expanded and continues to increase. Occasionally isolated populations of the moths are found in British Columbia’s Garry oak trees.
While gypsy moths feed on the leaves of hundreds of species of plants, their most common North American hosts are aspen and oak trees. In fact, gypsy moth caterpillars have a voracious appetite for oak leaves. They can completely defoliate trees! If all of the leaves are eaten in successive years, the infested trees may die, especially if they are weakened by diseases and other stressors. This could have a devastating effect on the species that depend upon the trees, and the adjacent habitats.
The Garry Oak Ecosystems Recovery Team (GOERT) believes that gypsy moths pose a critical threat to the integrity of Garry oak ecosystems. We support the objective of a gypsy moth free British Columbia and the 2004 approach to gypsy moth management (as presented to GOERT by the BC Ministry of Forests). However, this support comes with the following provisos:
- long term monitoring of ecological effects on non-target organisms is required,
- continuing development of policy and approaches to management of gypsy moth is required, and
- species-at-risk issues must be a high priority for consideration for any gypsy moth action.