Wasps Are Disappearing This Summer, and Scientists Are Worried

Wasps seem unusually scarce this summer, according to a wasp biologist who says students cannot find enough insects for their experiments and pest-control companies report a quiet year with few requests to remove nests. That is a sharp contrast with 2025's warm spring and hot summer, when 'plagues of wasps' filled headlines. So far the shortage is anecdotal: the Big Wasp Survey, the UK's only national wasp-monitoring survey, has not yet started sampling this summer.

The absence matters because wasps act as pest controllers, pollinators and decomposers in ecosystems. Spring 2026 began well, with warm, dry weather favouring new queens, called foundresses, as they build nests alone. But the season then swung between unprecedented heat, cold damp spells and unexpectedly chilly nights. Such extremes may have caused queens to abandon nests or die, shrinking the population that would otherwise have built up through summer.

Repeated heatwaves followed. Every insect has a heat limit called critical thermal maximum (CTmax) - beyond it, they suffer desiccation, muscle spasms and stupor. Honeybees can withstand roughly 49°C, yet UK ground surfaces exceeded 50°C in this summer's heatwaves. Wasps have defences, including wing-fanning to cool larvae, insulated nests and waxy cuticular hydrocarbons that coat and protect their exoskeletons from drying out. But their CTmax may be lower, around 45°C (113°F), leaving them more exposed to the extreme ground heat.

The wasps that are around also look unusually small, still 'spring-sized' even in August, when workers are normally much larger. Adult wasp size is fixed by the food larvae receive, so the pattern may reflect scarcer prey or larvae developing faster and pupating smaller in the heat. Global warming is thought to explain a century-long trend of social wasps shrinking in size.

Researchers are asking the public to photograph wasps feeding at picnics and submit images to the Wasp Picnic Survey 2026: Ham or Jam?, to help track what wasps eat this summer.