Budgies are able to see ultraviolet light, which is involved in courtship. The plumage patterns in ultraviolet are invisible to the human eye, unless you place your budgie under a UV lamp.
|Image © Mark Neville|
Budgies can resolve rapid movement much better than humans, for whom flickering at a rate greater than 50 Hz appears as continuous movement. Thus, humans are unable to distinguish individual ﬂashes of a ﬂuorescent light bulb oscillating at 60 Hz, but no more than that. Budgies have flicker tresholds of more than a 100 Hz!
|Image © volnistij-gorod.ru|