One fascinating aspect of birds is that they see in the ultraviolet wavelength spectra. Our eyes are unable to detect these levels of light but our birds can, and in fact, many objects have different reflective patterns of these UV spectra that we cannot see.
It is only a theory however I suspect our hands may have a different appearance in the UV coloration whether there are skincare products on them versus if they are clean. I have noticed a definite behavior difference of my own African Grey (Tesla of course) towards my hands whether I have lotion on them versus not and since this species has limited scent ability, and the hands don’t look any different in the visible light spectrum, I suspect it is the UV reflection difference.
I have had clients describe that their birds developed sudden aggression or fear towards them. Upon exhaustive discussion to try to resolve the cause of the biting, I found out that the client had used a new skin product right at that time. The clients almost invariably reported back that the birds resolved their behaviors as soon as the person discontinued the use of the product. Whose to say what would have happened if the person didn’t find out about this and continued using the product- perhaps the trust between the bird and the person would have disintegrated and we would have ended up with yet another unwanted parrot.
It would be fascinating to know whether a change in the UV coloration of some aspect of the bird’s environment, or of the bird’s caretakers (via a change in skincare, physiologic state, clothing), causes more behavioral abnormalities in our birds than we realize.
For additional mental stimulation, UV light sources can be placed near our birds. This will bring out more colors for our birds to see and enjoy, and possibly allow them to make better judgements in how to properly play with toys, preen their feathers, eat foods, react to things around them, and possibly generate additional nutrients (see the previous entry on African Greys and the importance of UV light).
And not to forget the importance for our reptiles, as well. They also see in the UV light and may see their food items better with this light. In addition and maybe more importantly, they may require UVB to activate vitamin D and absorb their calcium as well. However, there are reports of some UV lights being sold in this country having improper wavelength and causing some eye problems in some reptiles. For solid information on how to make sure your light source is firstly, safe and secondly, adequate, go to this website for more detailed information.
All in all, it reinforces the idea of how difficult yet how important it is to view the world around our animals through their eyes, not ours (literally, in this case)