This leucistic hummingbird has been appearing at my feeders for about six weeks in Tucson, Arizona. I posted previously, but could only get a shot through the window. It moved to another feeder and I was able to get a clear shot. I have identified it as a Costa's, given its small size and other markings. I have normal-pigmented Costa's at my feeders, as well as Anna's and Broad-billed. Taken with Canon 40D, and EF 300mm f/4 +1.4 x.