Why Bumblebees Are Struggling in UK Heatwaves – And How You Can Help

Lawns and non-Lawns

I have confused Facebook's algorithm so successfully that it thought I might be interested in Lawn Lovers UK, a group of over 15,000 enthusiasts of very green stripy lawns and weedkillers. They're currently mostly interested in ways of avoiding hosepipe bans in the heatwave which isn't - and I want to make this absolutely clear - in any way a consequence of the climate change which is apparently "hocus pocus".

I suspect the lawn lovers are not bumblebee enthusiasts. Making a tightly cut grass monoculture isn't one of the many things you can do for wild bees in your garden. Ecologically it's a short hop and a skip to the artificial grass group, who inhabit the ninth circle of hell. Incidentally, here's our back lawn for reference:

Don't Panic 

This kind of thing makes you realise how far we still have to go to persuade people to accept the changing reality which is now slapping us in the face.It's one of the reasons why I have been involved with the Bumblebee Conservation Trust for so long, as a supporter or trustee. The Trust usually gets the right balance between ringing the alarm on bumblebees and making people feel empowered to do something to help them. Their messaging is evidence based. They've actually done a lot too, from some pretty ambitious habitat creation projects to doing some important science and influencing policy. Give them money.

The other attraction is, or course, bumblebees.

Outside the rarified atmosphere of Lawn Lovers UK, most people love a bumble. Invertebrates with hedgehog appeal are few and far between for most people, lets be honest. I've got a huge soft spot for a fair number, but I accept that's not normal.  

Bumblebee problems are shared problems, as are the solutions. What's good for them is good for a whole range of pollinators. They are victims of habitat loss and fragmentation, and pesticide use. Their flying range is modest so they are particularly vulnerable to fragmentation, which makes our gardens such a valuable potential resource for them.

This means that species can go extinct quickly. The Great Yellow went from being perhaps our most common bee in the 60s to a small handful of colonies in the Scottish islands today.

They're also very obvious indicators of the climate change "which doesn't exist". It's no coincidence that the mighty Yellow is clinging on in the furthest northern lands it could find. Gen Z bumblebee fans may be surprised to hear that Bombus hypnorum, the Tree bumblebee, one of our most common bumblebees, has only been here for less than  20 years. It drifted up from France, as temperatures rose.     

This kind of species change is a niche interest. On the solitary bee front I was excited about the arrival of the Ivy bee a few years ago. I was warned about talking about it at dinner parties (but isn't she beautiful?). 

Bombus in Extremis

Now though the extreme heat we face gives me a better excuse to drone on. It represents an existential threat to bumblebees in the UK. I watched a good BBC short video about this featuring the Bumblebee Trust's chief boffin, Richard Comont. Richard sounded pretty depressed, which is unusual for him.  

Bumblebees started off in the Himalayas, and are well equipped for the cooler temperatures which honeybees like, for example. You don't need to know about bumblebee physiology to get this; they're furry, for goodness sake. This has meant they've been well suited to life in our cool temperate climate; they can even forage in light rain. 

Our recent summers have been very difficult for them. When it gets very hot honeybees have tactics like fanning to get by. They drink water too. Bumblebees don't. They can't fly in temperatures over 32c. As you get towards 40c, they cook to death. It's a quicker way to go, I guess. Even if they do manage to fly, they rely on nectar to keep their liquids up. Flowers respond to drought by not producing it. 

2022 was a terrible year for bumblebees. This year will be the same, although 2026 will be nuanced; I can guarantee Big Butterfly Count will show they have had a good year after the warm dry Spring. As usual, this will be seized on by some. Things will be all right and the whole narrative is some kind of Chris Packham related conspiracy theory. We've had an extraordinary number of different butterfly and moth species here this year, including Clouded Yellows, for the first time. 

So what's the point of this blog?

Firstly, I really worry we have now passed the tipping point for most bumblebees in the UK. I can't tell you how much it pains me to write this. I hope that at some future date they re-establish themselves here in a better, cooler world.

What Can We Do?

Secondly, all we can do is keep trying to mitigate the damage and concentrate on practical stuff. We may lose existing solitary and bumblebee species, but we will gain new ones like the Tree bumblebee and the Ivy bee. How fantastic it would be to have Carpenter bees, for example...

Do what the Trust recommends and we keep banging on about. Richard is talking about ponds now too, which makes a good deal of sense. There are wetland plants which are brilliant for bees, like the Yellow flag iris above or long flowering Purple loosestrife. 

Any ideas how we can bring the lawn lovers onside?