Figure 1. Example of aldehyde emissions and correlation with behavioural observation.

Results from a PTR-MS recording on four male and four female bed bugs. The thick horizontal lines indicate mating attempts of male on female (red), male on male (blue) or a second male trying to copulate an already established male-female couple (orange). A. Estimated concentrations of (E)-2-hexenal and (E)-2-octenal over the entire recording period. B. Observed (dashed black line) and calculated (green line) ion counts for the mass 57 which is produced from both (E)-2-hexenal and (E)-2-octenal.