# Asian Giant Hornet



## dudelt (Mar 18, 2013)

It probably came from British Columbia. A nest of them was found just over the border in September.


----------



## LAlldredge (Aug 16, 2018)

HarryVanderpool said:


> Hot off the press at the Daily Dead Fish Wrapper (Portland Oregonian), Asian giant hornets have been found in
> Washington State.
> Just what we need; another pest or disease to battle. It never ends!
> We best start cracking the book and get ahead of this one:
> https://www.oregonlive.com/environm...ling-hornet-turns-up-in-washington-state.html


Found this very useful article from Honeybeesuite about a beekeeper in France that has been dealing with them. He has some successful measures and controls. Rusty also updated it with the local siting you mention. https://www.honeybeesuite.com/beekeeping-with-asian-hornets/


----------



## Eric Walls (Feb 8, 2013)

Hey Harry,
I saw that article too, on Katu 
https://katu.com/news/local/invasive-giant-hornet-found-in-wa

Was also going to make a post about it. I hope this was just a rouge siting. Just what we need right now, another pest to deal with.
Eric


----------



## JoshuaW (Feb 2, 2015)

If the life cycle is like other wasps (like yellowjackets), only the queen overwinters, then builds a nest in spring. That means she has to forage to feed the first young, then she doesn't leave the nest. So very early spring is the time to set out bait stations.

I killed over 30 yellowjacket queens like this two years ago. I saw 2 yellowjackets this past year, so I'll do it again. Most of the queens drowned in pollen-patty remnants tossed into a bucket of standing rain-water.


----------



## grozzie2 (Jun 3, 2011)

dudelt said:


> It probably came from British Columbia. A nest of them was found just over the border in September.


Unlikely it came from the nest that was found and destroyed, as that nest was in Nanaimo, on Vancouver Island, so a big chunk of water between the nest and where this one was found. I spoke to the folks that found the nest and eradicated it only a couple days after it was dealt with.

The nest found in Nanaimo is an interesting story, there was a significant urgency to finding it as the discovery of those hornets was about the time of the year they would be starting to produce queens for wintering and starting new colonies next year. They knew it was somewhere in the area, one of the club beekeepers had seen one catching bees at a hive, so they caught it and forwarded the dead specimen to the provincial ag department for identification. When the nest was found, they used fire extinguishers to smother it in CO2 while digging it up and getting the combs and brood intact. They were putting the insects into alchohol as they pulled them out, knocked out by the CO2. An entimologist went over every dead insect and active brood cell to check for queens. One fertile laying queen was found, and no young queens either present or in development.

And just to give you an idea of how reslient these things are. I attended a meeting of the Nanaimo bee club a few days after the nest was found. One of the combs was passed around for us to take a good look at the larvae. That comb had spent 3 days in the fridge, and 2 days in the freezer at that point, and the larvae had not been fed. Some of them were still wiggling.

The question everybody has been asking since then, how did it get there, and are there more ? Lots of thoughts around 'arrived on a ship' but no real answers. The nest in Nanaimo was about a half mile from the harbour in a park. All the bee clubs on the island from Duncan up to Campbell River have had presentations that included show and tell with preserved specimens of those hornets. Everybody knows what they look like and will be on the lookout for them next spring. After the found nest was eradicated, no sign of them in traps or otherwise on the island, so there are high hopes the discovery was a 'one off'. 

I must admit, reading about another discovery in Blaine is not what I wanted to hear.


----------



## Eduardo Gomes (Nov 10, 2014)

By the photo (https://www.oregonlive.com/environm...ling-hornet-turns-up-in-washington-state.html) is the mandarinia hornet. In Europe the invading hornet is the velutine nigrithorax. If this hornet is established in your territory next year, I hope local authorities will allow the use of Trojan horses. France and Europe are paying dearly for not allowing this strategy.


----------



## grozzie2 (Jun 3, 2011)

Eduardo Gomes said:


> By the photo (https://www.oregonlive.com/environm...ling-hornet-turns-up-in-washington-state.html) is the mandarinia hornet. In Europe the invading hornet is the velutine nigrithorax. If this hornet is established in your territory next year, I hope local authorities will allow the use of Trojan horses. France and Europe are paying dearly for not allowing this strategy.


The nest found and destroyed in Nanaimo was confirmed to be the mandarina.


----------



## Juhani Lunden (Oct 3, 2013)

Eduardo Gomes said:


> I hope local authorities will allow the use of Trojan horses. France and Europe are paying dearly for not allowing this strategy.


Please explain!


----------



## Eduardo Gomes (Nov 10, 2014)

Juhani Lunden said:


> Please explain!


Velutina hornet has been progressing in Europe despite all efforts and techniques used. Trojan horses are the only known technique for attacking non-localized nests, which are estimated to be 80% of the total. Each nest produces about 300-500 new founding queens for the following year. It is clear to me that without a strategy that eliminates or greatly weakens non-localized nests, growth of the velutina hornet population will only be limited when food shortages are reached. By then it will be too late for most honey bee colonies, so far an important part of their diet in the summer and fall months.


----------



## little_john (Aug 4, 2014)

2018 paper - said to be the first on the subject of biological control of hornets using fungi:
https://www.researchgate.net/public...ts_against_the_invasive_hornet_Vespa_velutina
LJ


----------



## grozzie2 (Jun 3, 2011)

The hornet episode in Nanaimo was well documented and there have been many presentations about it. This video was done by the folks that went in and removed the nest, parts of it are a bit hokey, but there is some good stuff in there. Documenting the nest removal in Nanaimo starts about 2 minutes into the video. 

https://www.youtube.com/watch?v=DXZeS1g7oxM


----------



## LAlldredge (Aug 16, 2018)

At a little over 6 minutes you get to see the queen. Holy cow. Wow they were brave for going in at night and sticking their hand down that hole after blowing CO2. 

I think I’m glad you posted the link but we’re going to need a bigger boat.


----------



## Kuro (Jun 18, 2015)

OMG thanks for the video. I have heard that in some area in Japan they drink ‘giant hornet liqueur’ and enjoy stir-fried larvae……


----------



## lobottomee (May 3, 2015)

Can these hornets survive cold winters? Like those in Upstate NY?


----------



## grozzie2 (Jun 3, 2011)

lobottomee said:


> Can these hornets survive cold winters? Like those in Upstate NY?


They survive the winters on the northern islands in Japan, so yes, they can likely survive your winters.


----------



## Lburou (May 13, 2012)

LAlldredge said:


> Found this very useful article from Honeybeesuite about a beekeeper in France that has been dealing with them. He has some successful measures and controls. Rusty also updated it with the local siting you mention. https://www.honeybeesuite.com/beekeeping-with-asian-hornets/


I wish there was a like button for your post. I like it!


----------



## lobottomee (May 3, 2015)

Can you explain hot to do a "Trojan Horse" with these and where to find more information on the method? I did see a youtube video where a Beek in Brittany mentioned it, but not other information.

Thanks!


----------



## little_john (Aug 4, 2014)

lobottomee said:


> Can you explain hot to do a "Trojan Horse" with these and where to find more information on the method? I did see a youtube video where a Beek in Brittany mentioned it, but not other information.
> 
> Thanks!


post #11


----------



## grozzie2 (Jun 3, 2011)

lobottomee said:


> Can you explain hot to do a "Trojan Horse" with these and where to find more information on the method? I did see a youtube video where a Beek in Brittany mentioned it, but not other information.


Something to keep in mind, the hornets being discussed in Europe, and those recently found on the west coast are very different critters. If just using google to find information, note the difference between 'asian hornet' and 'giant asian hornet'.

From google at https://en.wikipedia.org/wiki/Asian_giant_hornet
========
The Asian giant hornet is sometimes confused with the yellow-legged hornet (Vespa velutina), also known as the Asian hornet, an invasive species of major concern across Europe, including the UK.
==========


----------



## Eduardo Gomes (Nov 10, 2014)

grozzie2 said:


> Something to keep in mind, the hornets being discussed in Europe, and those recently found on the west coast are very different critters. If just using google to find information, note the difference between 'asian hornet' and 'giant asian hornet'.


Yes. One big difference is in hunting mode, velutina hunts on a stationary flight outside the hive and mandarinia, from what I saw on youtube, enters the hive even when it is well populated, a behavior that velutine only exhibits when the hives are weak. Also the favorite nesting place for velutinas is on high tree branches and mandarinia prefers to nest in the ground. A link that gives a good summary of Poidatz's research on the velutine wasp and may be useful because some similarities should exist between the two species: https://beecare.bayer.com/media-center/beenow/detail/invaders-bring-new-challenges


----------



## Paul_B (May 30, 2015)

Would putting 1/2” wire over the entrance keep the hornet from getting into the hive?


----------



## GregB (Dec 26, 2017)

Paul_B said:


> Would putting 1/2” wire over the entrance keep the hornet from getting into the hive?


They are not THAT big.


----------



## Kuro (Jun 18, 2015)

GregV said:


> They are not THAT big.


Looked several Japanese websites and it seems that 7 mm works fine against the giant hornet.


----------



## elmer_fud (Apr 21, 2018)

Kuro said:


> Looked several Japanese websites and it seems that 7 mm works fine against the giant hornet.


Sounds like a metal mouse guard would work if it is attached well. 

I would still rather all of of the asian hornets get killed off in North America ASAP


----------



## Paul_B (May 30, 2015)

But they look HUGE lol


----------



## GregB (Dec 26, 2017)

Kuro said:


> Looked several Japanese websites and it seems that 7 mm works fine against the giant hornet.


0.5 inch ~ 12.5 mm


----------



## Nicksotherhoney (Jun 10, 2017)

I hope this was a fluke and they got all of them. I would think it would take a while for them to make it pass the Rockies.. any insight on how fast the could spread across the us?


----------



## rwlaw (May 4, 2009)

Nicksotherhoney said:


> I hope this was a fluke and they got all of them. I would think it would take a while for them to make it pass the Rockies.. any insight on how fast the could spread across the us?


As it sounds like a fertile queen was a stowaway that made it across the pacific. It’s anybody’s guess, eh?


----------



## grozzie2 (Jun 3, 2011)

Nicksotherhoney said:


> any insight on how fast the could spread across the us?


If they show up in the California almond groves for February, they will be all over the USA by April.


----------



## bfriendly (Jun 14, 2009)

The long version: https://www.youtube.com/watch?v=36TFu_W1Vio from WA dept of agriculture 

-US Beekeepers should report and document sightings to the department of agriculture, specifically state invasive species hotline/pest programs. Washington has a "hornet watch" map, website, & facebook. WSU has specific recommendations for beekeepers, not in depth at this time but I'd imagine more coming soon.. BC beekeepers should be aware and report to the invasive species council of BC.

-"pop bottle" traps, sticky board bait traps, and other diy traps are being tested. - Using red wine, banana peel, apple, fruit/jelly, vinegar, honey, sugar, syrup, and/or tree sap as bait with a drop of dish soap -like traps for yellow jackets- DIY "pop bottle" traps are made with a 2 liter pop bottle (or similar 1 gal jug, gatorade bottle, etc) with the top cut off and inverted (or instead triangle hole cut in the side), with entrance or hole opening somewhere around ~1" (or maybe larger, I don't know). 

-on a small scale Japanese beekeepers are using ~7mm(?) (just larger than 1/4") mesh screens in front of entrances, or sometimes net surrounds, both of which are not fully effective without additional traps in the apiary. For now commercial beekeepers may want to not place bees or move hives out of affected areas especially summer through early winter. Nets over each hive/pallet, perhaps, could be an option (~2"(?) or so visible thick temporary fencing net or fishing net that honey bees fly through but the giant hornets can't navigate). Sticky traps might be a solid option sticky trap video, also cool to check out the shaking entrance defense of Apis cerana (I think that's what it is)  Japanese entrance screen trap shown screen entrance trap video. Rectangular mesh is better than square. I think mesh screens that small seem likely to brush pollen off, but I've seen mouse screens of 3/8 or so used, and obviously not ideal for the bees depending on hive size but 7mm or 1/4" slats or screen might be do-able if the bees are crawling not flying. 

update- wa state trapping program and bottle trap instructions https://agr.wa.gov/departments/insects-pests-and-weeds/insects/hornets/trapping

Additional thoughts...They showed up on both Vancouver Island and the mainland in 2019, so it seems possible/likely we missed at least one previous generation and there might be other "hot spots" yet to be noticed around.


----------

