Saturday, August 8, 2015

Immature hummingbirds reign supreme – Las Vegas feeders are busy with the young




            Female hummers worked hard this spring and summer laying eggs and raising the young. Unfortunately for the mothers, the males simply went about their merry ways, defending territories and displaying their prowess of singing from the tops of trees.
            When I am walking home with the dogs at first light, I hear the Anna’s ‘sewing machine’ song coming from the trees at my next door neighbors’. When I get in front of my own home, I hear the whistle of the Costa’s coming from my bushes. Those are adult males letting the world know they are present and accounted for. But they are now in the minority.
            The yard is full of immature hummingbirds representing each of the three species that summer here: Black-chinned, Anna’s and Costa’s. My feeders frequently need fresh sweet water as they are kept busy from first light to last light. Hummingbirds are the first birds I see in the morning and the last birds I see in the evening. Sometimes it is so dark when I see the last one that all I can really detect is the silhouette of the bird perched on the feeder.
This picture was taken by a former student using her iPhone6
            When the birds are really young they are willing to have another bird sit with them at the feeder. I suspect that in most of these cases the two birds feeding together are nestlings, hatched from the same clutch and raised in the same nest. I have frequently seen two at a feeder, but have not been quick enough with the camera to catch an image of it.
I think this is an Anna's due to size and tail
As the birds get older and the male begins to develop his colored gorget, he also gets much more territorial. When the day is cool and my windows are open I hear the chattering a hummingbirds as the feeders get defended from all comers. There is so much of that going on it becomes a constant hum in the background. When I am outside I frequently see two dots fly in front of my face as the defender vanquishes the interloper.
Immature Costa's guarding a feeder
When I see one of these combatants I assume that the young male is the victor because that is who comes back to the feeder or the immediate area. Sometimes he sits at the feeder, but more often he sits on a stem of the bush closest to the feeder or at least located where he can keep an eye on it and make a mad dash to chases the interloper away.
He then moved to another vantage point, but he can still see the feeder
I know it’s difficult to identify the immature males, but I try any way. I have theories about what to look for, which could be disproved at any moment! One is: I notice the feathers surrounding the throat. If they are long and hairy I assume it’s a Costa’s, I look at the gorget feathers that are starting to develop. If they are narrow and long I again assume it’s a Costa’s. The tail is the real give away for me because the tail of the Costa’s is shorter than the wing tips, while those of the Black-chinned and Anna’s are longer.
Another Costa's feeding
Also, at my house the Costa’s males are the rulers, so the Costa’s immature definitely are to be found in greater numbers. Since I see so few of the other two species I am still working on an identification for them.
Probably the same Costa's watching the feeder
Soon the migrants will start to come through, and then I’ll have to try to identify immature Broad-tailed, Rufus and Calliope also. I think I may give up and just enjoy watching the activity at my feeders here in Las Vegas NV.