Situation of the Asian form of gypsy moth (Lymantria dispar) in Russia and in the world

Lymantria dispar occurs in Russia in at least two forms, the European form in European Russia (and also in western Europe) and the Asian form in the Russian Far East (and other far eastern countries). During an outbreak in the Russian Far East in the early 1990s, egg masses of L. dispar were found on Russian ships sailing from the Far East ports to the west coast of North America. Larvae blown from such ships may have been responsible for outbreaks of the Asian form of L. dispar in western Canada and USA. As a result, a Russian‐American lymantriid monitoring programme was set up, using pheromone and light traps to follow the occurrence and flight of Lymantria spp. around ports of the Russian Far East and in adjacent forest areas. These have shown a general decline in populations since 1992.