Two hummingbird species winter in Las Vegas NV – how to tell them apart

C Hummer taken from 2 feet away

                Here in Las Vegas NV we have two species that stay with us all winter – the Costa’s Hummingbird and the Anna’s Hummingbird. Even though we usually have at least one week, or more, of below freezing temperatures, they survive the winter with the help of feeders.

Anna's male, taken by a reader, used with permission

                When you look at pictures of hummers in the field guides they look so dissimilar, but seeing them in real life is a whole different story. The field guides use their best photos with the best light. The color of the gorget shows up well. When you see your hummer it may have entirely the wrong light on it. The gorget just looks dark; details are hard to see at best.  And then, of course, the hummer seldom stays long in one spot, so your look is fleeting.

                The more details you are aware of the better your chances of identifying the adult male hummer. The chances of getting a good identification of immature birds are slim, and females can be just as frustrating.

                After hours of looking and several really good photos, I feel a little more confident about differentiating between the Anna’s adult male and the Costa’s adult male that I see in my neighborhood.

                Let’s look at the similarities that exist between the Anna’s and Costa’s. These males are the only ones in our area that have colored heads. The color on the gorget is repeated on the top of the head. Our other summering hummers have green heads. This fact helps to eliminate choices in the summer, but doesn’t do us any good in the winter.

                The most obvious thing to look for is the shape of the gorget. The Costa’s gorget has very long side feathers that extend way down onto his shoulders. Behind his gorget at the sides and bottom there are long ‘hairy,’ perfectly white, feathers.

                Anna’s also has a gorget that extends to the side, but it is not so long, nor are the feathers themselves so long. The feathers next to the gorget are small and gray.

                Both birds have a white patch at the corner of the eye. The Costa’s patch joins with the white feathers along the side, while the Anna’s patch is cut off by more gorget feathers.

                The color of the gorget differs. While both will simply look dark in bad light, and have a rosy look in other lights, good light tells another story. Anna’s gorget is red-pink, yet if you see it in bright light it will look golden. Costa’s, on the other hand, looks purple and sometimes even shades towards the blue.

                A look at their breasts shows yet other differences. The Costa’s is speckled with a definite white stripe down the front and a green hue on the sides. Anna’s has a scalloped pattern on the feathers, no white stripe and tends towards the grey with just a hint of green.   

                Their tails also are different. Costa’s tail is shorter than the wing tips; Ann’s tail is longer than the wing tips.

                Even with all these things to look at, there will be days when identification is iffy at best. So I wish you good luck and good light in your efforts at hummingbird identification.