Japanese beetle

Japanese beetles are considered crop and garden pests. The larvae damage lawns. The adults, which often feed in swarms, can skeletonize trees and shrubs. They also attack flower buds and fruit.

Mammals (moles, shrews, skunks) and birds feed on the larvae and can control their populations to some extent. Natural predators of the insect (flies and wasps) have been imported from Japan. In fact, we can now see the presence of Istocheta aldrichi, a parasitoid tachinid fly that lays its eggs on Japanese beetles. The fly larva then develops inside the Japanese beetle, resulting in its death. The larva of the fly will then turn into a pupa, always inside the beetle, where it will spend the winter. Adults emerge in spring, around the same time as Japanese beetles. If you see parasitized Japanese beetles, it is important to leave them in the wild so that this predator can continue its life cycle. This is easily recognizable by the white dots (eggs), often on the Japanese beetle's thorax.