Very nice, with good detail on the bird. Looks like he just had lunch!
Did you get a chance to get some on a perch? That will often provide a less static, more dramatic pose and cleaner surroundings. I'm usually not very excited by birds on the ground, but that's just a personal preference.
Love the details particularly in the face! I'm like Diane, sometimes you don't have a choice but to shoot when they are on the ground, but a perch makes such a difference. Still, I like the surroundings and the cactus makes a nice touch. Now that I think about it, this is one that you might zoom in on the head and do a "portrait", then it doesn't matter if he is on the ground!
I enjoyed seeing this a lot when I got to this page. Especially all the color.
The bird being on the ground doesn't bother me. I checked a Wikipedia link and learned that as CM wrote, they are scavengers and their being on the ground is a common thing.
I can almost feel and smell the grasses, and as Warren wrote, the cactus does add a nice touch. The colors really pop. I think a bit could be trimmed from the top and leave enough cactus to tell the story, and come in a bit from the left. But those are personal preferences. I like Warren's portrait idea. And especially with this bird, with all the colors.