The courtship behaviour of the parasitoid wasp Venturia canescens was investigated. The courtship of this wasp had five behavioural components. Courtship behaviour could be grouped in two classes: successful courtship behaviour (behaviour leading to an actual mating) and unsuccessful courtship behaviour. The sex ratio and the weather affected the number of matings significantly: most matings occurred if a high sex ratio was used and during sunny weather. The age of the wasps had no significant effect on the number of matings. Biometrics; Reproduction; Reproductive behaviour; Ecology; Population dynamics; Population structure; Abiotic factors; Physical factors Venturia canescens (Ichneumonidae); Age; Courtship; Characteristics; Mating, weather & male & female age effect; Population sex ratio; Climate and weather none