On a glass roof. A not bad illustration of the anisodactyl pattern, the three toes forward/one back arrangement of some bird feet. Passerines, the song birds, also known as perching birds, have this layout. The members of order Passeriformes make up half of all bird species. Doves, however, even with the same toe-pattern, are members of the order Columbiformes.
Meanwhile, the zygodactyl pattern, with two forward/two back, are seen in woodpeckers, parrots, owls, Osprey, and others. There are other layouts as well. Ostriches are unique in having only two toes.
We were cat-sitting. The screened porch had a glass roof, a good containment pod for this invasive species. Cardinals, Robins, and Jays were some of the other avian life forms noted outside. A surprise was a quick visit by a female Ruby-throated Hummingbird, who was checking out the unopened red honeysuckle flowers.
Our close proximity to Prospect Park meant we saw Common Nighthawks over the Long Meadow about one hour before sunset on two nights: there were six overhead at once on Sunday.
And in the afternoons, the shadows of doves…
Backyard and Beyond 
What a great amusement opportunity for the cat! Loved the shadow picture.