Observed the gravel lined nest box through the New Balance Falcon Cam for a while late this afternoon under cloudy skies, winds from the NW at 28 MPH, and temps in low twenties.  The female was moving around again, quite a bit inside the nest box, especially pushing the gravel around and creating a bowl.  She lowers her breast down, stretches her head forward, and uses her feet to push the gravel behind her.  This means egg laying is getting ever closer!

Literature Cited:

White, C. M., N. J. Clum, T. J. Cade and W. G. Hunt. 2002. Peregrine Falcon (Falco peregrinus), version 2.0. In The Birds of North America (A. F. Poole and F. B. Gill, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bna.660

Nest Construction Process:  On ledges, consists of scraping bowl in substrate, frequently initiated by male, but by both male and female. Falcon lies on breast and pushes feet backward to produce depression (see Fig. 18 in Nelson 1970b). Substrate consists of dirt, sand, fine gravel, or sometimes decomposed fecal material or decomposed lining materials of old stick nest. Male may construct several scrapes on same ledge or on different ledges. No material deliberately added, but bones and other debris may be pulled around sitting bird to form circle of material around edge of scrape. Scraping also occurs in stick nests of other birds. Behavior as much courtship ritual as “nest-building” (Wrege and Cade 1977).

Made a short visit under late day sun with adult female perched outer edge of nest box, enjoying the sun.  She has been in or near the nest box the last number of days.  She is lethargic and slow in moving around, with egg laying time very near by!