You may be spotting bodies of dead bumblebees lying across pavements near you in the summer months.

There are several reasons for this, some to do with the weather and some very much due to humans.

Bumblebees are social, living in colonies that are maintained by very active workers with a relatively short lifespan of 4-6 weeks. This means, that in a relatively short space of time, older bees die off and to prevent disease making it’s way through the colony, the healthy young workers bring out their dead, moving them far away from their colony.

Another factor is the weather. It was the warmest June on record in England (and the second hottest for the whole UK) in 2026 and other high temperatures are expected this summer.

Thermal stress in bees is caused by this kind of extreme heat. Prolonged heat exposure alters development and threatens long-term population stability.

Heatwaves also severely disrupt reproduction, flight capacity and ability to forage. Social insects including bees rely on cooling behaviour for example fanning their wings when things get too hot to buffer the hive but there are limits as to how effective this is in extreme heat.

As it gets hotter bee foraging activity may increase, and they may cover greater distances. Bees can thermoregulate themselves by moving heat around their body while in flight, but extremes of temperature can affect their health.

Don’t kill your........

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