I know there are some feather mites that burrow in the feather shaft, so that is one kind of mite you can't see. you can treat it with ivermectin. oral administration is best. but yeah, most of the time other parasites are easy to spot and get rid of.You should be able to see mites/lice on the bird. That would be my guess. Mites are almost microscopic, but you can see them. Lice are easy to see.
best thing to do would be to treat for parasites, ivermectin for internal and organic feeding material (blood, etc). that is great for worms - biting mites or burrowing feather mites. those you can't see because they are in the actual feather shaft. you could give him a dip that treats most bugs, permethrin mix is what most use. that way if they still do what they are doing you know it is a personality trait. my birds do that, stand on one leg and shake their wings when they get excited (I have 2 in the house, so that is quite often) but I don't know about the head shaking. I would treat for the bugs though. they can be a serious problem real fast.I am brand new to pigeons. I bought two adult pairs. One pair shakes their head a lot and will lift up one foot and shake it. That is the white and brown pair. the other dark pair shakes their heads some. Mites? or possible a known behavior?
I use Ivomec (that is the ivermectin) that treats the worms and internal parasites as well as parasites that feed on your birds. this also works well for many kinds of mites. you can find the dosing information on the bottle. I got it from the vet, and see as how my birds were hand fed, I was able to give it a bit differently. I used a dropper, 2 drops in the mouth per bird. repeat in 2 weeks, to make sure you get everything. I am big on prevention, and I tend to be a bit OCD, so I do this (well I plan to do this, my birds are only 6 months old) once a year, even though my kids don't go outside and are not exposed to other birds. as far as permethrin I was told to use 1 tablespoon per 1 gallon of warm water as a dip. same principle would apply to make a spray. you can get permethrin online or at any farm supply store, same as the Ivomec. be careful about the ants, they can kill new hatchlings. do some research and see what you think will work best for you. this is what I do, but I do not know of this is what will work best for you. I agree you might wait until your birds are done hatching and the babies are eating on their own, but if you see the parents out of the area you have them in, and you feel the threat about the ants is great, I would personally spray around with the permethrin. you don't have to drown the area, just mist it a bit. permethrin has a great ability to deter those pests for up to 28 days. again, up to you, this is just a thought, an option to consider.Is the Ivermectin and Permethrin dosages found on this site? These are king pigeons. One is sitting on an egg already so I might wait on treating her - she does not show signs like the white ones. I an also concerned about fire ants - get rid of any i see in the flight pen.