Color helps hummingbirds communicate

Despite my best attempts, a dime-sized creature foiled me. I put up a hummingbird feeder at our camping at Burro Creek near Wikiup, Arizona, to attract some hummers, and it did.   

It was quickly found by two male and one female Anna's hummingbirds. I believe one man claimed it as his territory.  

I wanted full-color photos of the little fellow flying. I used my new high-end Nikon mirrorless camera and a 600mm lens with a 1.4x doubler for an 840mm lens. I increased the ISO to shoot at 1/2000th of a second at 20 fps. I was ready.

Almost immediately, I got good photographs. But I wasn't taking shots of Anna's gorget, that magnificent crimson cape over his neck and head.  

It appeared virtually black in my photos. After two days and 2,500 photos, I captured this amazing creature's entire color.  

Male hummingbird gorgets are like icing on a multi-layered cake. In “Birds of North America,” John James Audubon characterized the rufous hummingbird male as “like a breathing gem, or magic carbuncle of glowing fire, stretching out its gorgeous ruff, as if to emulate the sun itself in splendour.”  

I must pause before continuing. Birds may view colors differently than humans. We see red, green, and blue with three cones. Birds can perceive UV light with a fourth cone.   

Imagine the options. For instance, red and blue become purple. Can birds combine red, blue, and ultraviolet to create an unimaginable color? How many more combinations can they see than we?  

We believe the gorget is great, but how does another hummingbird see it? The gorget's color display is unusual. It has no light-absorbing or reflecting pigments like fruits, dyes, and paint.  

The color derives from the feathers' smallest filaments. A microscope shows small mountain ranges of air bubbles that bend and refract light depending on the angle of light to the particles.