Hummingbirds (2)

There is a rule-of-thumb ornithologists follow: If you see a pair of birds, robins, say, and they look so  much like each other you can't tell which is male, which female, you can guess that they are more or less faithful to each other and share in the raising of the young. If the female is dull and drab, and the male has brightly colored dramatic plumage, peacocks, say, you can bet the male struts around looking pretty until he attracts a female, mates with her, and never looks at her again, but goes off looking for another female, while she raises the family.

Hummingbirds are in this second group. Here's how it works with Costa's Hummingbird. The female looks perfectly ordinary. The male, as a juvenile, looks more or less like the female. He has not got his equipment ready yet to fight for a female and mate with her, so by resembling a female, he stays out of the fray till he is prepared. The sign that he is ready is when he changes into his nuptial plumage, which in a hummer usually means slowly developing brilliant colors around his face and gorget.

The Costa's Hummingbird is a popular bird, mainly on account of his nuptial finery. The female, as we have already said, is very ordinary, a green back, whitish underparts, faded reddish wavy lines under the throat, a slightly decurved bill.

 

 

The adult male has crown and gorget a brilliant violet, an almost impossible color to catch in a photograph. To top that off, great long  extensions (in the same brilliant color) sweep back from his mouth. here is a picture of an immature male just beginning the long extensions.

And here is an adult.

 

Notice here, though I have promised brilliant violet color, it just looks black. What is happening is, the light is a reflecting light, and if you are not at exactly the right angle the color will come back black. In life, if you were looking at this one right now, the bird might make the slightest move and suddenly dazzle you. Let's see if I can get one at the right angle.

That gives you the idea. Here's a couple more pictures, mostly half black and half violet.