Factors influencing the seasonal life history of the pitcher‐plant mosquito, Wyeomyia smithii

Abstract

Abstract. 1. The effects of resource levels, thermal microclimate, and seasonal oviposition patterns on fecundity and survivorship in the pitcher‐plant mosquito, Wyeomyia smithii (Coq.), were examined at a northern Wisconsin bog over the course of 2 years. Wyeomyia smithii are bivoltine at this locality, thereby enabling the study of summer and overwintering generations separately.2. Nutrient resources of W. smithii were not limiting and there was no indication of density‐dependent survivorship or fecundity.3. Oviposition rates were highest in young, large pitchers and individual mosquitoes appeared to allocate only a few eggs to any one leaf.4. Winter was the harsh season, and the principal manifestation of seasonal harshness was reduced survivorship.5. Overwintering W. smithii that had been oviposited later in the summer had a higher odds of survival than those oviposited earlier in the summer.6. It was concluded that dispersal of eggs among many pitchers serves to spread the risk of encountering lethal winter temperatures among spatially unpredictable patches.