Could we really see more swarms of wasps because of hot and dry weather?

It has been a hot and dry summer for the UK so far, with scorching conditions expected to continue in August.

Record-breaking temperatures and months of sparse rainfall have resulted in dramatic changes to the natural world, with fields parched from a lack of water and burnt by wildfires.

Reports have suggested there could be another change as a result of the heat and lack of rain: a surge in the number of wasps.

But leading experts tell The Independent this is by no means a given - and the dry weather could even threaten their population.

Professor Seirian Sumner, a behavioural ecologist who co-founded a national tally of the wasp population, said drought conditions could limit their food.

This is because parched landscapes will mean less flower resources and therefore less food for insects - such as flies and caterpillars - which wasps eat.

“Actually, I’d be a bit concerned about the wasp population,” she says.

Prof Sumner says wasps “had a good start to the summer”, with warm springs supporting queens - just out of hibernation - to forage and build nests.

“But this uncharacteristically hot and dry weather that we’re experiencing at the moment which is not typical, our ecosystems are not adapted to deal with that,” she says.

“I think that could possibly have an impact on the wasp prey populations, which will have a knock-on effect on the wasp populations. But at the moment, we don’t know.”

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This is a crucial point for Prof Sumner, who says it is too early to make any judgement on how the weather will impact wasp populations this year.

“At this point in the summer, when the wasp populations are still growing, we cannot say anything,” she says.

Adam Hart, the other founder of the Big Wasp Survey, says scientists do not know yet what impact - if any - the climate crisis and its warmer temperatures will have on wasp populations.

“The Big Wasp Survey I’m a part of is collecting data. Other people are collecting data,” the Royal Entomological Society fellow says.

“But trying to find out if any particular year is to do with something like climate change is almost impossible. You have to look at the pattern over a long period of time.

“And the reality is that we see certain summers when there are lots of wasps, boom years for wasps. We see other summers when there were very few wasps.”

The Universityof Gloucester entomologist adds: “The exact effects of climate change, are unsure, but as we go through the coming yours and get more data on it, we will be able to find out more.”

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Prof Hart says it is not as simple as to say warm weather means more wasps, with some types thriving in hotter temperatures and some not.

Both experts agree that even if it feels as if there are more wasps in the air during hotter weather, this may just be down to behavioural changes: both from humans and the insects themselves.

Humans are more likely to spend time outside, including eating lunch in the open air - which could lead to more interactions with wasps.

Meanwhile, the insects will be more active when it is warm, as they forage for longer, Prof Sumner says.

This could be one explanation for a bug exterminator claiming to be dealing with more call-outs to wasps this year - as reported in UK media - rather than a booming population.