Reflective windows and birds

I'm unsure what the proper window nomenclature is, but our windows of our house have a slight reflective tint on the outside. The more light coming from outside, the more reflective the surface becomes. The result is that many territorial birds frequently find themselves battling a reflection of themselves. Interestingly enough, the only bird to demonstrate self-recognition (being able to recognize oneself in a mirror) is a magpie, putting it alongside dolphins, elephants and all great apes.

Although it's very detrimental for their energy reserves, it does give us a great view of some birds as they are unable to see us peering through the other side. Even with binoculars it is impossible to view these small skittish birds from up close, so needless to say, it's a real treat when I hear a bird rapping at the window!

This male Grey-Headed Kingfisher is highly territorial and after a while of pecking his reflection, he took time to cough up a pellet. 

This sunbird has a nest in our yard and he frequently attack himself.