Thanks to everyone who took the time to look at the photos and make a
comment and I do feel a bit silly that I forgot birds have feet. Most
people are suggesting Band-tailed Pigeons which is probably a good
guess. I'm going to stay undecided because I do think that pattern on
their underside is real -- it is present on each of the birds -- and not
something I can find on any photos of Band-tails.

--
John Riegsecker
Gig Harbor
jriegsecker at pobox dot com