Anyone (and most of the rest) who experienced car sickness knows that the difference between what the eye sees, and the balance says, causes nausea.
Assuming that pigeons have a sense of balance, and a magnetic sense of direction, if there was a way to make them disgree then it might cause discomfort.
So, a magnetic field with rotating direction might severely disrupt their activities.
In humans, 1 second cycles of movement are quite effective. A magnetic field with rotation frequency of 1s would be a starting point.
A huge 3-phase motor winding type device without the rotor might do the trick. The magnetic field would not need to be strong; just similar magnitude to that of the Earth. I wonder if a complete building could be protected?
As a side experiment, all humans who have remnant sensitivity, may suffer similar nausea.
*B is the magnetic flux density, measured in Tesla-- Ling, Jul 23 2016 Taking Leicester Square pigeons to train as racing pigeons https://news.google...=1278,1916883&hl=en...believe that etc.. [not_morrison_rm, Jul 24 2016] Not always so sweet. https://www.youtube...watch?v=aH53ofk5ESk [MaxwellBuchanan, Jul 24 2016] Poisoning pigeons in the park https://www.youtube...watch?v=yhuMLpdnOjYAvian cleansing. [8th of 7, Jul 24 2016] So, a way of making the feathered rats spew from both ends ?... works for me [+]-- FlyingToaster, Jul 23 2016 Kill them. Kill them all. Spare not even the children, lest the evil persist ...-- 8th of 7, Jul 23 2016 I quite like pigeons. They're smarter than some people of whom I can think.-- xenzag, Jul 23 2016 They're also partially edible.-- MaxwellBuchanan, Jul 23 2016 //They're also partially edible.
Linky. Remembered this from me London days.-- not_morrison_rm, Jul 24 2016 beautiful sweet clever birds.-- po, Jul 24 2016 Yes, until they get out of hand. <link>-- MaxwellBuchanan, Jul 24 2016 // beautiful sweet clever birds. //
No, [po], that's parrots. Pigeons are disgusting, verminous, disease-carrying scavengers with the intellect of doorknobs.
Or is that Belgians ? Could be either ...-- 8th of 7, Jul 24 2016 They won more wartime medals than any other anmals-- po, Jul 24 2016 Didn't know that Belgians had won that many medals ... what for ? Chemical warfare ? That's just the normal smell of the drains ....-- 8th of 7, Jul 24 2016 If a pigeon was running for president of the USA, I would vote for it.-- xenzag, Jul 24 2016 //They won more wartime medals than any other anmals//
Yes, but only because the fool who decided to award medals to animals didn't have the idea until horses were no longer a major part of the military. It was pretty much a case of having to award the medals to either a pigeon or the most recent officer's lunch (sometimes both together).
It was also discovered, sadly too late, that a pigeon with two ounces of bronze pinned to its chest was severely impaired in the flying department.-- MaxwellBuchanan, Jul 24 2016 Worked well as body armour, though.-- 8th of 7, Jul 24 2016 Not so much, though. The only difference would be a 2" diameter hole through the pigeon, as opposed to a 7.6mm hole.-- MaxwellBuchanan, Jul 24 2016 That sounds like a cue for a practical test, and possibly a song, too ... <link>-- 8th of 7, Jul 24 2016 What [xenzag] said. And then some.-- blissmiss, Jul 24 2016 yes, if I had a vote.-- po, Jul 25 2016 // 2" diameter hole through the pigeon //
An impromptu test using a 60mm diameter x 3mm thick brass disk, a small frozen chicken (fully defrosted) and a .30-06 FMJ round (balistically comparable to the German 7.92mm round) at a range of 50m does not result in a 60mm diameter hole through the chicken. Not unexpectedly, it simply results in no chicken whatsoever.-- 8th of 7, Jul 25 2016 random, halfbakery