Why do cockchafers only come out in may?

Cockchafers, or May bugs, typically emerge in May as this aligns with their life cycle, which involves several years of development in the larval stage beneath the soil. The warmer temperatures and increased availability of food sources during spring trigger their metamorphosis into adults. This timing allows them to mate and reproduce when conditions are optimal for their survival. Consequently, their seasonal emergence is closely tied to environmental cues that signal the onset of spring.