Asian hornet traps and baits - please review what you've used

[robbohenn]

It looks like the drink bottles do much better than the proprietory traps. Do you just leave the top off or do they have an entrance lower down?

 

[Parsonage Bees]

Sunny weekend ahead. I'm putting out a couple of bait trays to see what's about. This photo from a month ago. Flies and wasps visit.
Tray 1: sugar syrup/jam/pinch of yeast (who has cassis or for that matter spare lager in the house)
Tray 2: mashed up shrimps (who has prawns, see above)

 

[Karol]

Trapping spring queens will reduce the number of potential nests and I'd hardly consider that counter productive. Even if it does result in bigger nests the destruction of one of those will mean less hornet population in the vicinity and reduced effort in locating and destroying. Taking NO action is not an option unless you're willing to stand by and watch the invasion.

Taking no action?

The NBU are doing a fantastic job eliminating nests. At present that is the only action that is required. Monitor, report, destroy. IF and only if the NBU are overwhelmed should further measures be taken. Setting spring traps now when velutina is not established is just pure lunacy. Spring trapping hasn't worked in continental Europe and that's a lesson that needs to be learned here.

When and if the time comes that velutina becomes established, then more aggressive measures will need to be taken. Those measures I recommend would be to use fipronil custard. That's NOT taking no action. It's about taking effective action that won't make things worse.

 

[Karol]

Maybe you need to keep looking?

Well if you've found something then please share.

 

[Karol]

That presumes forage is limited
Is it?

Any idea what biomass a single mated filth fly will produce in one year in the absence of predation?

 

[Erichalfbee]

Do you mean these?

 

[Karol]

Do you mean these?

View attachment 37833

Typically flies that visit faecal matter and carrion such as bluebottles, greenbottles and the like.

 

[robbohenn]

The tops are put on, I cut the two outer sides of a triangle and bend the flap down and inwards on opposite sides. This seems to make it more difficult for them to get out. It's not fool-proof but I have seen them escape from the specialist traps too!

 

[Erichalfbee]

Any idea what biomass a single mated filth fly will produce in one year in the absence of predation?

Ok. Go on then.

 

[robbohenn]

It looks like the drink bottles do much better than the proprietory traps. Do you just leave the top off or do they have an entrance lower down?

The tops are put on, I cut the two outer sides of a triangle and bend the flap down and inwards on opposite sides. This seems to make it more difficult for them to get out. It's not fool-proof but I have seen them escape from the specialist traps too!

 

[jenkinsbrynmair]

Any idea what biomass a single mated filth fly will produce in one year in the absence of predation?

shitloads?

 

[OldFarm]

Ive seen photos of the AH compared to EH and bees and wasps but ive not seen photos of queen AH compared to workers. What is the size and appearance differences. Does anyone know?

I haven't seen photos of workers and queens side by side, but timing of sighting may be more significant. The only Asian Hornets flying before 1st May are almost always queens. She starts her nest around April and the first workers take 7 weeks to emerge, these workers will be small. The cycle speeds up and the workers get bigger as the number of workers grows - larvae are better fed and there is better temperature control. The queen will fly with the workers for the first 2 - 3 week, so early May, you could come across workers or a queen. The queen then doesn't leave the nest until she moves to the secondary nest, she won't be found out on the wing. The drones start to emerge early September and new queens two weeks later, they stay in the nest for 2 weeks, so probably on the wing for mating and maybe forage from the beginning of October, before they start hibernation. Weather can shift the cycle in either direction.

 

[ericbeaumont]

filth fly

An undiscovered world: met several basking flies last week, identified by BeeWitch as the Noon Fly; never heard of it, nor seen one before.

 

[Karol]

Ok. Go on then.

She will lay circa 500 eggs in her lifetime. Assuming 50% are female and there are 5 generations in one year (there can be as many as 8) this equates to 250× 250x250x250x250 female flies (for expediency I'll ignore male flies in the calculation). The average weight of a fly is 0.000007Kg. If all were to survive the biomass calculates out at 6,800 metric tonnes. (Even at four generations this is 27 metric tonnes).

Among the very many predators of flies including arachnids and birds, the most effective predators are vespines. So, if we spring trap and destroy native vespines we quickly create conditions to support velutina.

 

[Somerford]

Which is a totally unrealistic and unattainable proposition which is why it shouldn't be entertained because it will help velutina become established. Good for trap sellers but bad for beekeepers.

I concur that trapping would require participation everywhere by everyone not just beekeepers for this strategy to suppress velutina which is unethical and nothing short of ecological vandalism.

One of the benefits of fipronil custard is that it doesn't require anything of the sort of intensity or cost that trapping requires. Why? Because velutina workers are forced to visit bee hives because bees are the only real concentrated source of insect prey at a time of nest maturation. This provides the means for beekeepers to remotely destroy nests in a very targetted and ecologically sensitive manner because action only needs to be taken when there is evidence of velutina and that action will prevent proliferation. Trapping is indiscriminate and anticipatory and used irrespective of whether there's a problem or not.

I'm more than happy to push the custard on these little blighters but it is not allowed.....

my trap allows bycatch to escape and won't allow v crabro in either

 

[fian]

I have seen how velutine workers ambush Germanic vespula workers. The Vv does not distinguish between vespula bees or any other insect that can be ambushed. The only Hymenoptera that can cope with it is EH since they are both the same size.

 

[Karol]

I'm more than happy to push the custard on these little blighters but it is not allowed.....

my trap allows bycatch to escape and won't allow v crabro in either

Can you substantiate that your trap doesn't retain vespine queens?

 

[Gilberdyke John]

Taking no action?

The NBU are doing a fantastic job eliminating nests. At present that is the only action that is required. Monitor, report, destroy. IF and only if the NBU are overwhelmed should further measures be taken. Setting spring traps now when velutina is not established is just pure lunacy. Spring trapping hasn't worked in continental Europe and that's a lesson that needs to be learned here.

When and if the time comes that velutina becomes established, then more aggressive measures will need to be taken. Those measures I recommend would be to use fipronil custard. That's NOT taking no action. It's about taking effective action that won't make things worse.

Are you deliberately missing the point being suggested that stating spring trapping was a bad idea and which I replied to? You say traps won't work in autumn and wring your hands about bycatch despite timing spring trapping being used during restricted period to minimize that.
I don't disagree the NBU are doing Stirling work but it's reactive. Killing queens alongside natural failure reduces the number of target nests to find and deal with. If the hornet colony is stronger it follows more traffic will be observable and tracking simplified. Ten target colonies instead of fifty or more gives a military advantage towards subjugating the threat.

 

[Gilberdyke John]

Strikes me that having fewer, larger nests is bad news. Think about bees - they require a decent size colony to do well. The colony size releases workers to forage. Smaller colonies tend not to prosper.

If faced with locating a few large nests (targets) compared with lots of smaller nests I think I'll go for the few.

 

[Gilberdyke John]

Well if you've found something then please share.

No I haven't. Possibly because I aren't looking but simply because you haven't found evidence of a negative doesn't imply the existence of a positive.