Gentle giants and flying humbugs

Hornet colonies decline in autumn while honey bees form their winter cluster

Two hornets eating a fallen appleIn May I mentioned coming across a dead hornet (Vespa crabro) under a log in the woods and then going back a few weeks later to find it still there, but mostly consumed by mycelium.

Looking at the pictures again, I can see now that it was a female worker, which must have crawled away to die after the natural death of the colony at the end of autumn.

Despite panic-filled articles warning against 'angry' hornets, European hornets are placid creatures which aren't aggressive and don't sting without reason. These gentle giants don't deserve their reputation of being intent on attacking anyone who looks at them. That sort of behaviour is more often related to humans and I can only suppose that those who put forward such ideas are projecting.

Like their smaller relations, wasps (Vespula germanica), they take large numbers of insects we regard as pests and feed the masticated pulp to their larvae. At other times of the year they help to clear away rotting wood (used in nest construction) and fallen fruit, which is part of their summer and autumn diet. I put them in the category I refer to as 'cleaners'.

It was interesting last year to see that dead hornet in the woods, but this year we've noticed a marked increase in live sightings. You hear their loud, droning buzz before you see a hornet and their size makes them easy to spot in flight, which is a lazy meandering through the trees at about 2m. At this time of year the colony is on the verge of dying, with only the queen overwintering, so unless temperatures stay above 10°C there will be few sightings after the end of October.

Home ground

The increase in numbers makes me wonder where the hornets are nesting. Hornets often nest in the dark spaces provided by the hollow trunks of old trees, but this woodland is young, only 20 years old, and there is little other woodland nearby. They are also said to build nests in sheds, chimneys and, according to the Bee, Wasp and Ant Recording Society, occasionally in cavities within the mounds of meadow ants (Lasius flavus).

There are some magnificent ant mounds just 30 or so metres from the southern edge of the woods and I'm curious to know if one has been taken over by hornets. A careful investigation is called for there. 

A honey bee gets a head start on the syrupAs hornet colonies close down, the colonies of honey bees (Apis mellifera) reduce in size, though worker bees born in autumn will, with adequate food supplies, survive until spring. In order to enhance their survival over winter, we have fed the colony we caught this spring with sugar-syrup mixed with a nutrient supplement made for bees.

This is in addition to their own honey stores, which they are keeping for themselves. The colony we acquired last year gathered very plentiful stores over summer and has more than enough to take them to next year when forage is available again. Provisioned with this amount of food, we're optimistic that these 'flying humbugs' will be ready for a good start in spring. 

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