when will this madness stop!!

[maddydog]

Or sign which show why the humans are on the road to nowhere.

Amen to that! Hopefully there will be a few species left after we've gone.

 

[maddydog]

But after a while, we get fed up with the two notes it sings

Must be one of them X factor song thrushes

 

[madasafish]

Must be one of them X factor song thrushes

Can't be an X factor song thrush...It sings in tune...

 

[Karol]

I do tend to think that figure is quite an exaggeration. IIRC 11-15kg max is the figure they were talking about in the New Zealand aphid forests where wasps are active 365.
I suspect it is much less in the UK.

Try page 137:

http://www.academia.edu/4129909/Spr..._natural_history_of_social_and_solitary_wasps

2 wasps collected circa 20g of butterfly flesh in 3 days, i.e. approx. 3.3g each per day.

Average wasp nest circa 5000 wasps (I've seen plenty several times bigger than that) equating to 16.5Kg per day! Collected weight is not the same as eradicated weight as with most insect prey wasps pare away limbs and wings to reduce air resistance in flight. The length of the hunting season in the UK can easily last for 6 months.

Bear in mind that a large part of insect prey is made from carbohydrate that larvae regurgitate to feed their adults which is then essentially expired as carbon dioxide.

As I've tried to explain with regards to the New Zealand paper that you keep quoting, the paper is flawed because much of the sampling was done during the sweet feeding part of the wasp life cycle when wasps are bringing back little in the way of protein back to the nest because there is little if any remaining brood to feed.

I understand the argument Hivemaker that healthy wasp populations are a good means of controlling other insect pests but in this instance wasp populations aren't healthy, they're down by circa 90% compared to previous years based on pest control nest treatment figures that we monitor in our customer base and wasps are equally if not more prone to pesticides as queen wasps are highly vulnerable in spring to systemic pesticides at field margins.

 

[Karol]

Read an article today in the Telegraph on the same subject. They put the decline down to loss of insects. Sure enough pesticides will do that it is fairly obvious. The decline in numbers is over a very short period that roughly coincides with the presence of the Asian Hornet. We are told this is a veracious feeder on all insects and I was told, on good authority, that the lack of insects is a sign that hornet colonies are nearby. There was also a discussion on the forum about the weight of insects required to maintain a hornet nest. I suspect there may be two factors at work here and maybe the investigators have not joined the dots! Someone researching the effects of pesticides may ignore, or not understand, the effects of a voracious predator in competition for insects. Just a thought!

Not a bad thought but VV isn't sufficiently distributed throughout Europe to account for the dramatic fall in insect numbers. However, on a similar vein of thought the emergence of the wood ant super colony in Switzerland could very well be a contributory factor simply for shear scale:

http://www.bbc.co.uk/programmes/p05rgmbt/p05rglwg

 

[Hivemaker.]

I understand the argument Hivemaker that healthy wasp populations are a good means of controlling other insect pests but in this instance wasp populations aren't healthy, they're down by circa 90% compared to previous years

Perhaps their populations are not healthy because they have been doing too good a job at eradicating other insects and eaten themselves out of house and home...so to speak.

Four to five thousands tonnes of other insects per square mile destroyed by wasps must make a large impact on their numbers, more so if the insects the wasps prey on have a slower breeding cycle or need more exacting conditions to breed and survive than wasps do.

 

[Karol]

I accept the argument that you make because in years gone by we observed alternating cyclical patterns of wasp and fly populations and indeed wasp and tick populations. However, for the past six or so years that cycling of populations has ceased with consistently low wasp populations since 2012 more than long enough for other insect populations to recover and flourish.

 

[oliver90owner]

I suspect that some of the posters on this thread still puff away at cigarettes. The ones with even a little common sense seem to be in the minority.

In the olden days, invaders used to rape and pillage villages and the countryside (think here Vilkings and, later on, armies). Nowadays the human race is raping and pillaging the whole planet. Go figure the sense in that.

 

[Beefriendly]

2 wasps collected circa 20g of butterfly flesh in 3 days, i.e. approx. 3.3g each per day.

Its the extrapolation to 2 tons that has me giggling. Do you know what 2 tons of insects looks like?
Elephants, on average weight 1 metric ton.
So here's a visual clue.'

 

[maddydog]

Nowadays the human race is raping and pillaging the whole planet. Go figure the sense in that.

The animal fable 'scorpion and the frog' springs to my mind. Those who haven't heard of it should Google it between cigs

 

[maddydog]

Its the extrapolation to 2 tons that has me giggling. Do you know what 2 tons of insects looks like?
Elephants, on average weight 1 metric ton.
So here's a visual clue.'

Doesn't look so crazy to me when, as other posters have pointed out, water, poor conversion rate, and dissection of prey is taken in to account.
If a bee colony collects 100lbs of pollen per season how do the numbers stack up?
Interesting, but roll in spring

 

[Beefriendly]

Assuming the highly unlikely possibility that a wasps nest uses 2 metric tons of insects then it consumes them in an approx 4 month period, which equates to over 16lbs of insects per day.
Their nests would need to have Tardis like properties just to fit that amount of biomass inside...the picture below shows approx 1/2lb of insects...can anyone visualize 32x that amount being taken inside a small wasps nest each day during daylight hours. With over 100 nests per square mile estimated.

Can you physically fit 32x more insects than shown in the above picture inside a wasps, nest like the one below, every day for 4 months????

 

[Hivemaker.]

Assuming the highly unlikely possibility that a wasps nest uses 2 metric tons of insects then it consumes them in an approx 4 month period

I doubt they would survive on such small quantity of insect food, would have to be a very small nest to do so.

An average sized wasp nest will eradicate between 4 to 5 metric tons of other insects during a season, and there can be up to one thousand wasp nests per square mile.

 

[user 6228]

Its the extrapolation to 2 tons that has me giggling. Do you know what 2 tons of insects looks like?
Elephants, on average weight 1 metric ton.
So here's a visual clue.'

lets put this in proportion.
The annual production of just one neonictiod is sufficient to kill

between 10 and 1000 cubic KILOMETRES of Honey bees


annual production of imacloprid in china is estimated to be greater than 20,000 tonnes
the toxic dose for a bee is some where between 1 and 10 nano grams

production in grammes greater than 2x10^10 (10 followed by 10 zeros)
(grammes in a tonne = 10^6 )
toxic doses greater than 2x10^19 (10 followed by 19 zeros)
(1000,000,000 nano gms in a gm)
honey bees weigh 0.1gms
total weight of dead honeybees 2 x 10^ 12 tonnes
honey bees have a similar density to water.
a cubic metre weighs one tonne
a cubic kilometre weighs 10^9 tonnes







Lundin O, Rundlöf M, Smith HG, Fries I, Bommarco R. Neonicotinoid Insecticides and Their Impacts on Bees: A Systematic Review of Research Approaches and Identification of Knowledge Gaps. Raine NE, ed. PLoS ONE. 2015;10(8):e0136928. doi:10.1371/journal.pone.0136928.

Environ Sci Pollut Res Int. 2015 Jan;22(1):103-18. doi: 10.1007/s11356-014-3180-5. Epub 2014 Jun 18.
A review of the direct and indirect effects of neonicotinoids and fipronil on vertebrate wildlife.
Gibbons D1, Morrissey C, Mineau P.

 

[Beefriendly]

I doubt they would survive on such small quantity of insect food, would have to be a very small nest to do so.

I was too clever by far...I extrapolated for average size of nest in North Yorkshire, not those gigantic nests you get outside of the tundra zone.

 

[Hivemaker.]

I was too clever by far...I extrapolated for average size of nest in North Yorkshire, not those gigantic nests you get outside of the tundra zone.

Even more food would be required in a colder place like Yorkshire to keep the nest warm, even if the wasp nests were highly insulated with kingspan/reticel. etc.
They would need nearer to five tonnes a season to survive.

Five Elephants worth into their nest in four months.

 

[Finman]

Five Elephants worth into their nest in four months.

It should produce 1000 kg wasps to the garden. When they sit on plants, plants would squeeze flat.

A big beehive has 7 kg bees.

 

[Millet]

I wonder if the wasps have started eating the birds when they have depleted the insect population..

 

[Beefriendly]

Even more food would be required in a colder place like Yorkshire to keep the nest warm, even if the wasp nests were highly insulated with kingspan/reticel. etc.
They would need nearer to five tonnes a season to survive.

Five Elephants worth into their nest in four months.

Good point, I'd forgotten about heat generation.
I now estimate that it increases the amount of insects required at a rate of 1 metric ton per 100 miles as you travel North. When you get up to where Millet keeps his bees you are up to about 12 elephants worth per 4 months.
On the positive side the heat generation is so good you can toast bread 2 foot from the nest entrance.

 

[Finman]

I wonder if the wasps have started eating the birds when they have depleted the insect population..

Birds eate wasps, you should know. Cats eate birds.
.