I've only seen this dove in the morning when it's too dark for me to get a good photo. I thought originally that it was a dark version of a white-winged because I saw lots of white when it was in flight, but the white that it does have might stand out more since its so dark. However, the tail is pointed and I'm not seeing white on the wings when perched. Is it a dark Mourning Dove? Its feathers are coming out. Does that mean it's a youngster? Doesn't act young and no parents around.
I took this photo a couple of days ago. The White-winged dove had been sunnng on a rock among some oxalis and ajuga flowers where it looked so pretty that I tried to take its photo. Even though I was inside the house, the dove's sixth sense told it that I was taking a photo and so it got up. I took the shot anyway. When I uploaded it, I discovered that there was another dove sunning himself on the rocks behind the White-winged dove. It might be the same dove. If not, it's another very dark one.
It came back and the sun is out! Still didn't get a good picture though. Can't seem to focus on this one. I left hoping he would bathe in the pond. He's preening like mad and seems very unhappy. I'm sure it's hard being different! I'm adding this photo though to show the very dark shoulders.
I knew that if I posted some lousy pictures of this dove, she/he would finally pose for some decent ones! I'm going to add a bunch more that show her back, side, and wings. Here's a shot with the tail splayed.
Doesn't look too happy, with feathers missing around its neck. Very unlikely there's anything you can do about it though - in the first place, getting a diagnosis of the cause from a vet would mean catching it for examination, and that might be too much stress for it.