Bumblebees

It is probably not going too far to say that if humans are going to thrive in the future, and have anything like the standard of living that we in the developed world enjoy today, then we simply have to look after our bumblebees. With dedication and a little luck perhaps we can conserve the burly, good-natured bumblebee for future generations to enjoy.

Dave Goulson (Professor of Biology at the University of Sussex, specializing in the ecology and conservation of bumblebees.)

I like bumblebees. All fuzz and buzz in a cuddly, miniaturist sort of way; stocky bundles of black and yellow with a hairiness that you mistake for a soft furriness.

You could say my feelings towards them were only enhanced when, for the first time, a queen decided that a wall cavity in the house would be a good place for a nest. Of course, I’d rather she hadn’t chosen the house, and what’s more one of the walls of our bedroom. At first we imagined machinery had struck a remarkably mellifluous note – either a tractor sound muffled by an intervening hill or the neighbouring farmer’s grain drying kiln. But in fact it was the constant low hum of the bees – barely above a whisper – and certainly not a sound that would disturb our slumbers. And it’s a relief to learn that a colony is unlikely to get larger than 400 bees. Compare that to honeybees averaging 50,000 and wasps 3 to 6,000 in a colony.

Surfing the web, I didn’t come across anyone who had a bad word to say about the bumblebee. In the UK there’s even an organisation devoted exclusively to them: Bumblebee Conservation Trust. I see that New Zealand has now followed suit: NZ Bumblebee Conservation Trust.

Why do they get such great press? No doubt uppermost for Jane and Joe Bloggs is the thought that they’re not likely to get stung by a bumblebee. Who even knows of someone who has? Some people say they bite, but according to entomologists in the know, the nip’s so gentle you wouldn’t even notice it.

Then there are the commercial growers of tomatoes. In the late 1980s it was discovered that bumblebees get real sexy when hanging out with tomato flowers. It all comes down to good vibrations. It’s the humble bumble, not the honeybee, that can reach the correct frequency by vibrating flight muscles. Called ‘buzz pollination’ or ‘floral vibration’, get enough bumblebees to hang out in a greenhouse and they’ll stir up a storm of pollen dust. So, they bred bumblebees for the job of pollinating tomatoes. You need to get the vibes right with blueberries as well – and we’ve got five massive bushes. So, welcome to our wall space little critters – we need you!

Apparently, you can simulate ‘buzz pollination’ by briefly touching the back of the flower with a buzzing electric toothbrush! I don’t even want to imagine having a go at that! What would I have to do, set aside forever to pollinate our tomatoes and blueberries?

I don’t know if there still is, but there used to be a lab in New Zealand that bred bumblebees. Many were exported. Some to England to try and re-establish them in areas where they’d died out due to habitat loss (hedgerows to nest in and flower-rich meadows to collect pollen and nectar), and the use of modern fertilizers and pesticides. You’ll appreciate the irony: our bumblebees came from England in the first place! Introduced to pollinate crops of red clover.

For years we used to get clover-rich hay from Stuart Harvey’s aptly named Clover Downs farm – some paddocks were full of red clover grown for seed. Not long before he died and the farm was sold, I was round there hefting bales onto the trailer and noticed an oddly constructed plastic box propped up by the trunk of a pine tree. When I asked Stuart about it, he said he’d bought in bumblebees from a lab in the North Island.

Stuart had noticed a decline in the population since a change in farming practices and crops on the land surrounding his place. Pastoral, otherwise known as extensive grazing of sheep and beef, replaced by intensive cropping of wheat and barley. As a result, the bees lost habitat as hedgerows and shelterbelts were taken out, and some of the pesticides used were toxic to bees. Stuart had kept many gorse hedgerow fences and still had paddocks full of a variety of plant species, so he was hoping to boost the number of bumblebees actually living on his own land.

Stuart, on a working farm, felt an urgent need to import bumblebees. On our ten-acre block, we’ve noticed bumblebee numbers increasing as a matter of course over many years. No gorse hedges here (although there used to be long before we arrived), but an abundance of red and white clover in our paddocks, all manner of flowers in June’s large garden, fruit trees and berry bushes in abundance, and numerous habitats we’ve established that suit, amongst many other creatures, bumblebees.

The spring and summer of 2021/2022 we had a bumblebee nest in an outhouse wall. No nest in there this time round, which reinforces what I read recently about them not returning the following season to the same nesting site. And now their mates are in our bedroom wall. My hope is that this newly observed phenomenon of using wall cavities ‘close to home’ means that our bumblebee population continues to increase at a pace.

Seeing bumblebees out and about pollinating our crops is reassuring after a twenty-year stint keeping a couple of honeybee hives came to an end some years ago. A commercial beekeeper every year puts hives close to a flowering rape crop on the neighbouring farm, so we still see plenty of honeybees around as well. But you need a variety of insects and birds to successfully pollinate our extensive range of plants.

Add smelly feet to ‘floral vibrations’ and you have a very efficient pollinator. Their feet leave behind an odour in a flower and that’s why you’ll observe one being so picky – no point wasting your energy in a flower that’s already been plundered by another worker bee. And add big (relative to their overall size) pollen carrying baskets, which are located on their back legs, and that’s a heap of pollen that can be transported back to the nest on a single foray.

Some of our bumblebees had to waste energy and precious time while I photographed them going in and out of the only hole connected to their nest in our wall; I sat for several minutes directly in line with the valley in the corrugated iron verandah roofing they were using to approach the entrance: I didn’t get so much as an angry buzz or aggressive in-your-face fly past.

Reflecting on all the above, how could I not be with Dave Goulsen when it comes to wanting to “conserve the burly, good-natured bumblebee for future generations to enjoy”.