causes

Sleuthing...

title

Tue, 04/06/2021 - 12:40 - by: Barry Crabtree

It’s got to be one of the saddest sights for a beekeeper - piles of dead bees outside the hive. Even sadder is when you see all those bees have full pollen baskets. This was the sight seen by a Suffolk beekeeper when they went to look at their hive recently.

So what’s killed the bees? Poisoning? Have crops been sprayed? Have verges been sprayed? What’s going on?

dead bees

A sample of bees were dispatched to the regional bee inspector. Meanwhile lets take a look at the pollen the bees were bringing in to see if that gives any clues. From a sample of pollen baskets from four of the bees, the pollen was all the same, almost spherical and just under 20µm in diameter.

Pollen samples

The closest looking samples seemed to be willow. It was clearly not oilseed rape, nor was it dandelion. That pretty much rules out verge or crop spraying, so what is it that is killing the bees?

The bee inspector suggested it might be chilling. The bees just got too cold out foraging and couldn’t make it back before they seized up and died.

The weather for that day did indeed show a drop in the afternoon temperature from a high of 9ºC down to 2ºC by 9pm.

So that’s most likely the cause. A cold snap caught the bees out.