Blue tit (Cyanistes caeruleus)

Interestingly, the plumage of the blue tit has a very distinctive colour pattern in the ultraviolet spectrum, which is invisible to the human eye. These colour variations play a role in mate selection.

In Europe the population is considered viable and there are no signs of significant population change. IUCN classifies it as Least Concern (LC) .. :-) .. It occurs also in neighbouring parts of Asia.