The UK's bumblebees are facing a dire situation, with heatwaves posing a significant threat to their survival. These furry insects, uniquely adapted to our cooler climate, are struggling to cope with the intense heat, which is causing them to 'keel over' and die. The issue is twofold: their bodies are generating more heat, and their thick coats and round bodies make it difficult for them to cool down. This is a critical problem, as bumblebees are essential pollinators, and their decline could have far-reaching consequences for ecosystems and agriculture.
One of the most concerning aspects of this situation is the impact of heatwaves on bumblebee populations. Dr. Richard Comont, the Trust's science manager, explains that once air temperatures reach around 28C to 32C, bumblebees can start to struggle to fly without overheating. This means they cannot forage for food, which is essential for their survival. As Comont puts it, 'They actually cook themselves from the inside out.' The BeeWalk data from 2022, when the UK had three official summer heatwaves and temperatures reached 40.3C, shows a significant drop in population numbers.
The effects of heatwaves on bumblebees can last beyond the summer. Data from BeeWalk shows that overall queen numbers were below average in March, April, and May 2023. This is a cause for concern, as it suggests that the impact of heatwaves on bumblebee populations may be long-lasting. However, scientists stress that warm, sunny weather is not automatically bad for bumblebees. In fact, previous warm years have been good for some species, particularly those with more southerly ranges.
The problem is extreme heat and drought. As well as their overheating bodies, bumblebees are also facing dwindling supplies of food. Colonies depend on workers bringing back a steady supply of nectar and pollen through the summer. If flowering plants begin to dry up, they produce less, which means bumblebees have to work harder to find food. This can lead to larvae developing more slowly, colonies growing less strongly, and fewer new queens being produced for the following year.
The impact of climate change on bumblebees is a significant concern. Rising global temperatures are putting the UK on course for more frequent and intense heatwaves, which could have devastating consequences for bumblebee populations. Conservationists say the best way to help is by creating more flower-rich habitats, so bumblebees can find food even as the climate becomes more extreme. Dr. Sarah Beynon, an insect expert, has planted meadows, willows, hedgerows, tussocky grasses, and late-flowering crops on her farm in west Wales to give insects food through the summer. She believes that people do not need acres of land to help; a pot of native wildflowers on a doorstep or windowsill can act as a small refuelling stop for insects moving through a human-dominated landscape.
In my opinion, the situation facing bumblebees is a stark reminder of the impact of climate change on our natural world. It is a call to action for all of us to take steps to protect our pollinators and the ecosystems they support. We must act now to create more flower-rich habitats and reduce the impact of extreme heat and drought on bumblebees. Only then can we ensure the survival of these essential insects and the health of our planet.
