Abstract
It has been reported in some species that the peak of male captures in pheromone traps occurs some time later than the peak of oviposition of females in the field. This study, using a model for the female pheromone trap competing for male attraction, showed that this time lag is caused by the gradual increase in the trap attraction efficiency following the decrease in mating female numbers as a result of death or exhaustion of mating capacity. The time lag in captures is found if enough males capable of mating survive after female numbers begin to decrease. This occurs when females emerge earlier than males, and/or when the maximum number of matings in a male's lifetime is greater. The low attraction efficiency of traps and low mortality in adult males intensify these effects on the time lag in the male captures.
