I was more under the assumption they were recent touch-ups. However they have censored things before, like simply taking out tail markings on planes being flown by test/capture units, etc.
Okay, assuming the photos are real, I don't see them as a bright orange bird's head. I don't know where you get orange [edit: not YOU you... you all, "they" etc], unless some verbal/text description was put down in writing at the time.
Throughout many air forces there are special camo markings on noses of aircraft. The Germans (we have many 109s with dotted or special cowlings on the nose), the Italians (see my C205 with brown nose showing but splinter uppers), and others as well. The nose was the most prominent part and it stuck up the most. Putting the plane under camo nets and revetments and the like often left them with the visible nose, so often you had this touched up with special camo.
To me, looking at those pictures, under the new assumption they're actual photos: That doesn't look like orange. Nor does it look like orange and yellow flame-like patterns. The quality of the photos and the scans are so poor that the noise introduced into the original photo is what they are seeing and not the actual paint that was there. That's my opinion.
It looks like winter whitewash that's flaked off mostly. It also looks like there are brush strokes in it, like it was roughly applied and quickly. There is also the possibility they painted over certain areas that needed repairs and touchups with their own color of green. They had several shades and some of the field-applied greens on zekes and Kis etc, were rather pale.
In a couple of the photos it looks like a more solid color, but then in others you see the paint is gone, flaked off, or perhaps "baked on" to the point it's blending in with the normal Olive Drab coloring.
See here:
or here:
Look at the shades of green around the lower cowling. You can see in other angles and other pictures it appears whatever this is was applied all the way around and underneath. However in the above photos it is already resembling the shades of OD green on other parts of the airframe. At least, patches are starting to look that way.
You can see the darker color on the spinner and cowling. The Japanese were not in the habit of painting teeth on any of their planes, nor eyes. The teeth and eyes are very much in the US pattern of markings.
I suggest this is a top coat, either protective after repair or perhaps some camo green as a temporary measure, and they simply painted it OVER the AVG-style shark's teeth.
That is what it looks like. That is the far more likely answer. There also were a limited number of captured P-40Es in use by the Japanese. They are fairly well documented photographically and historically. Some sources say they had 10 operational.
There is no record so far as I have read about a bright blazoned parrot headed P-40 (other than the P-40N in US stateside training service). I suspect sensationalizing and misinterpretation of old photos at this point.
EDIT: The ww2aircraft link you listed seems to suggest the US crews painted it this way. While not outside the realm of possibility I am still doubtful as to the color used and the intent. They had some very creative and elaborate paintings, cat faces, grotesque human skulls, sabertooth teeth... This is rather abstract and almost Van Gogh-ish and does not seem to fit artwork. The teeth and eye, sure, but the rest? I seriously doubt it.
P.S. When would it have had US markings? Apparently it was captured off the ship, flown to Japan, and repainted all-green for propoganda movies....
Never used in service regardless.
