In their fourth week of life, the chicks undergo significant changes almost daily.  Around day 25, the brown tips to the secondaries become clearly visible, and the number of coloured feathers visible on the breast increases noticeably.  Behaviourally, they are rarely resting on their tarsi anymore at this age.

At day 26, the development continues in terms of the increasing covering of juvenile feathers on the breast.  The area on the head bare of down also continues to expand.