By day 29, the chicks often have their faces largely free of down, giving them a white-capped appearance.  On their backs, the remaining down often appears to be clumped together in certain areas, with extensive areas instead revealing the dark juvenile feathers. 

It’s often around day 30 that the chicks seem to turn into “real” peregrines almost overnight, very rapidly losing much of the down on their breast, thus revealing the heavily streaked breast feathers they will be carrying for the next year. 

By day 31, the chicks often become actively interested in losing their down, preening themselves and sometimes ending up with feathers stuck to their beak as a result.  From the back they are looking increasingly dark, with the wing feathers approaching full length.