Wasps

Biology and Habitat

The over-wintering and fertilised Queen emerges from hibernation around mid-late April and searches for a suitable site for her colony. From chewed bark and dry timber mixed with saliva, she makes the “initial” cell or starter nest about the size of a golf ball. She will then lay in individual chambers between 10-20 eggs, feeding emerging larvae on insects and other invertebrates. The emergent adult workers take over the tasks of enlarging the nest and providing food for the subsequent eggs laid by the queen. All worker wasps are sterile females. Ultimately, by the late summer the population of a wasp nest could be between 3000-5000.

In the late summer the Queen produces “new” queens and male wasps, they mate and the fertilised queens fly away to select suitable hibernation sites, the males remain with the “queen” and the sterile workers. This is the time when the wasps become more of a problem, there are no duties for the workers/males and they begin to feed on ripe/over-ripe fruit and this can cause a tipsy behaviour leading to aggression towards anyone interfering with them. The nest survives as long as the weather allows, the onset of the cold winter to kill off all the wasps, and only the hibernating queens survive to start new colonies the following spring (only a small percent of the hibernating queens survive to start new colonies).

Control

Wasps are generally easy to control using a number of different products, it is the use of protective equipment that allows the pest control officer to gain access to the nest and therefore treat using either an insecticide dust (1% bendiocarb) or an aerosol nest destroyer spray. Wasps never re-infest old nests and therefore although it is recommended, it is not necessary to remove treated nests.