Day 17: how they have grown!

May 30, 2018 in In the Nest Box, lawrence peregrines, Peregrine Falcons Eastern Massachusetts, Peregrine Falcons Massachusetts

With sunrise at 5:11 AM, the peregrines started off the day with clear skies, wind from the NE at 9MPH, and the temp at 62F.  The day ahead calls for sunny skies, with a high near 74. Calm wind becoming east 5 to 8 mph in the morning.

2018.0530.1-001This morning the female dragged in a large bird, likely a rock pigeon, with a gray body, and a gray rounded tail with dark terminal band.  Unlike prior feedings, this was freshly caught and not stripped of feathers before being brought to the nest box.  The female went into a frenzy stripping the feathers and then feeding the nestlings.  The nest box at one point, was a swirl of feathers.  As the female was feeding, you are able to see the size of the nestlings, and how they have grown much larger over past two weeks!

 

2018.0530.2-001By day 17, the chicks have already grown considerably relative to the size of their parents, but still have a long way to go until they match their stature and reach full size.  In terms of feeding, the frequency of feeding visits by the parents depends on the size of the brood, but researchers have found that four meals per day was the norm during the nestling period.  Others have observed anywhere from 4-8 feeding visits per day, with some observing as many as 6-11 feeding visits per day.  Most observers agree that feeding begins very early in the morning, often before it is light enough for humans to see!

 

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