This morning the peregrines began the day with overcast skies, winds from the NE at 3MPH, and temp at 55F. The day ahead calls for cloudy skies, then gradually becoming mostly sunny, with a high near 66. Calm wind becoming southeast around 5 mph in the afternoon.

By day 24 the facial pattern behind the eyes is becoming increasingly evident, and some colouration is becoming visible on the upper breast as juvenile feathers develop beneath the down.   The legs are now just about fully developed, and thus banding can take place from this time onward. For these three peregrines, banding is scheduled for the end of the this week.  A number of other chicks in the extended Boston area either have been banded, or are scheduled to be banded.

After the chicks can stand, at 22-23 days, the begging posture becomes more horizontal, though they feed in a normal standing position, and direct themselves at the parent’s beak. At about this age, they will start to regurgitate castings composed of indigestible remains, and wiping of the sides of the beak back and forth against the nest box edges.  Also, at about 24 days, signs of self-feeding became more pronounced with nestlings starting to garb at food instead of just begging for it!

Literature cited:

Ratcliffe, D. 1993. The Peregrine Falcon. 2nd ed. Carlton, England: T. and A. D. Poyser.

The Canadian Peregrine Foundation, Peregrine Falcon Development – Age Guide; http://www.peregrine-foundation.ca/info/ageguide.html