Fig. 11.5.

Facial feather expression. When irritated, magpies sleek down all their feathers but directly above and below the eye; feathers are raised, slightly in the first image and fully extended in the second image. It looks as if the bird has eyebrows, and note that the feathers under the beak are sleeked down. Once the cause of the irritation was removed, the feathers returned to their original position and the bird took no further action and not once vocalised. Non-verbal signals, i.e. signals that do not depend on voice, can thus be very important and may avoid conflict.11