Asian Hornets

asian hornet on flowerAsian hornet on lavender

This month’s Bee Craft magazine has a feature on this dreaded hornet that has popped up again, this time in Fowey, Cornwall.

I’m reminded based of last year’s National Honey show where I’d gone to hear Tom Seeley speak and was lucky to also catch an excellent presentation by Heather Mattila  also from the USA.

Heather had returned from a trip to Japan and Cambodia researching Asian Hornets and in particular to learn how the local Beekeepers, and more importantly the native Bees, were adapting to this predator that was now spreading across Europe. (Otis, Gard & Mattila, Heather & Duc Pham, Hanh & Nguyen, Lien & Knight, Olivia. (2013). Novel defense by Asian honey bees (Apis cerana) to attacks by social wasps (Vespa spp)

“The asian hornets can also remove 1cm of wood of a hive

entrance in a couple of hours.”

They had spent weeks observing hives as they were targets and then destroyed by the hornets. She had some pretty horrific statistics, an Asian Hornet can take 40 bees in a minute, and so after targeting a vulnerable hive, the initial scout hornet will return with a terrifying gang able to devour a whole colony of bees in a few short hours. The asian hornets can also remove 1cm of wood of a hive entrance in a couple of hours.

Japan.

In Japan the technique of ‘swamping’ a scout hornet was observed by her team. This has also been observed when bees attack a wasp in the West. bees will completely surround a predator quivering in a ball producing heat. The bees seem to know that the wasps ( or in Japan the Hornet) will perish by suffocation and the excessive heat. Wasps can withstand a mere 2degrees higher temperature than the hornet.

“…an Asian Hornet can take 40 bees in a minute”

In Vietnam, whilst still hoping to find some hopeful news about how native bees were defending themselves against the Asian Hornet , one of the assistants said that a local farmer was saying how the bees were eating her chicken dung. None of them could believe this, however with only days left and no solid notions of how the hornets selected their victim colonies, they set up a camera to watch the bees eating the old dung.

hornet & wasp comparisons
ulacarnell.com/wp-content/uploads/2018/09/asian-hornet-info-graphic.jpg”>hornet & wasp comparisons

This had ne

[/caption]This had never been heard of before so they really weren’t expecting to either see it happening, let alone learn of any benefit to the Bees from this activity.

It was therefore to everyone’s surprise when they caught the Bees settling on the fresh dung taking it up in lumps with their mandibles.

Following the Bees back to the apiary, they noticed that some colonies had dapples of a brown substance around their landing boards. Could this be the dung?

One of the behaviours noticed during their research was that the hornets would target a colony in an apiary.To begin with,  a single hornet, would wipe its abdomen across the entrance of the hive. This appeared to be ‘marking’ them with a pheromone as very soon afterwards a group of hornets would appear and start taking the Bees one at a time as they left or returned to the hive. Heather’s team were also testing the hornet pheromones, placing samples on paper outside of the hives. The hives with the pheromone coated paper were then more inclined to dapple their hives with the dung, and they also chewed up the paper removing it from outside their hives.

“…as we tend to learn more FROM the bees than they learn

from us..”

It was then noticed that the hives with spotting of dung were less likely to be visited by the hornets. The next question naturally was what was it about the dung that put off the hornets? The smell was an obvious suggestion, however with old dung the scent is minimal and Heather’s team then wondered if the spotting of lumps of dung made it harder for the scout hornets to rub their abdomens across the front of the hive. Without the pheromone, the scout hornet was unable to mark hives to be attacked. They then learned that the bees preferred chicken and pig dung to any other offerings!

This got me thinking about our own bees and how we can protect them, or more to the point, as we tend to learn more FROM the bees than they learn from us, how would wild bees naturally protect themselves from such predators? For very many years we would keep bees in straw skeps coated with a dung mixture, could this have been an idea learned from watching bees defend themselves against European wasps and hornets? I do wish that I had thought of this earlier this summer and maybe a little bit of spotting of dung may have protected my bees from the fatal wasp attacks late this summer. It also makes me wonder about the belief that chickens and bees go well together…

In the mean time, bee lovers are keeping an eye out on the flowering ivy, in case a dreaded Asian Hornet be spotted. Should this alien species be noticed, a photograph and location should be immediately sent to; alertnonnative@ceh.ac.uk

Social media is full of posts of the governments latest sightings, now two in Fowey, Cornwall along with some terrifying snippets of information regarding the vast quantities of queens each nest can produce and the distances each queen can fly, especially when aided by strong winds!

“…It also makes me wonder about the belief that chickens

and bees go well together…”

Somerset Beekeepers recently took a delegation to Jersey to see the hornet nests and how the local bee population is coping with this new threat to bees. The University of Exeter has some slightly more positive news, they’ve been using radio-tracking to track the hornet nests after tagging any captured hornets. They have been trialling this in Southern France and Jersey with success in finding five previously undiscovered nests.

Hornets & wasps comparisons
uploads/2018/09/Hornets-wasps-comparisons.jpg”>Hornets & wasps comparisons

In the mean time, we all need to rema

[/caption]In the mean time, we all need to remain vigilant, raise awareness so that more people, not just bee keepers, are able to spot and identify an Asian Hornet, and keep a close eye on our precious bees, ensuring that they are in the best of health, so as not to be easy pickings for any passing eastern beasts!

photographs used have been taken from the Somerset Beekeepers Facebook Page

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