Choose the colour that best describes the back of the bird.
The colour choices progress from the lightest (White or pale) to the darkest (Black, purple or dark).
Colour can be subjective. Differing light conditions affect perception. The Advisor makes allowance for this. While
you should be as accurate as possible, you may pick a colour within a range. For example, if you noted only that the
colour was light, then choose one of the light colours white, yellow or olive, etc. This is better than picking
Unknown. If you knew the colour was light and chose Unknown, the Advisor would include all colours,
including the dark ones, as valid. Obviously the more accurate your colour choice is, the better your ID will be.
Therefore answer Unknown for colour only if completely uncertain. The RULES that are used to describe a bird
are flexible in this colour choice matter. More than one light colour is used to describe a light area and more than one
dark colour for a dark area. And when more than one colour e.g. a black and white back exists then either colour choice
of White or Black is acceptable.