Thursday, December 2, 2010

Winter Birds

As a kid I was always told that birds fly south for the winter. The thing is, for a lot of birds, this is the south they fly to. Though we do have some year-round residents and some birds that fly even further south as well. Perhaps this is one of the reasons why Texas is such a mecca for birdwatching. There's always something to see. Yesterday I managed to snap a few photos of a couple of the birds that spend the winter here. They had come for suet, which is a great food to put out to get a wide variety of birds. Both seed eaters and insect eaters like it.

This is an Orange-crowned Warbler. Most warblers spend the winter in South America, but this species has its winter range as far north as Texas. We get one other winter warbler here called the Yellow-rumped Warbler, which is more vibrantly colored, but I didn't see any yesterday.

The orange crown isn't always visible, but I have seen a glimpse of it a few times before. It does seem odd to me how many birds are named after a marking or other part of their anatomy that's really hard to see in the field. You'd think they would pick something more obvious. (Though, the yellow rump on a Yellow-rumped Warbler is pretty obvious, so they did a good job there.)
This is one of my favorites, a Ruby-crowned Kinglet. They're one of the smallest songbirds around, but they're also very feisty! They're not shy at all. I've had them get practically right up in my face before. Again, the ruby crown is not always visible, but I've seen them raise it a couple of times when the bird was getting excited or something. I've been told that the song of the RCK is really beautiful, but unfortunately they only sing it during breeding season, when they're not here. Still, I look forward to the RCK's arrival in winter because they just so cute.
Here's the Orange-Crowned Warbler enjoying some suet with a Carolina Chickadee. The chickadees stay here all year, and they really love sunflower seeds, but they'll take suet too.

And then it seems like whenever a flock of songbirds are gathered around the suet, that somehow signals the Golden-fronted Woodpeckers that it's safe to show up. Then they scare away the smaller birds from the suet. This is Mr. Woodpecker. You can tell from the red on top of his head. His wife joined him right after, but I didn't get a good picture of her. She looks the same but without the red, just yellow on her head. I occasionally see the smaller Ladderbacked Woodpeckers, and once I saw a Downy Woodpecker, but I see Golden-fronteds just about every day. They're also a year-round resident.

While I'm on the subject of winter bird behavior, there's something I've noticed that's been puzzling me, but I think I've figured it out. All year there are Great-tailed Grackles here. You know grackles, largish, long-tailed, long thin-billed birds. The males are iridescent black while the females are brown, and their "song" is a bunch of loud, mechanical sounding noises. Even though they're here all year, the winter is the only time I see these huge flocks of them descending upon the parking lots and shopping centers like something out of an Alfred Hitchcock movie. The rest of the year you only see some of them here and there.

I think what's going on is there are actually two populations of grackles. Some of them stay here year-round, while others migrate away and only come back in the winter. Therefore, here we get a sudden increase in the grackle population in winter, when the migratory grackles arrive to spend the winter with their more sedentary relatives.

What I don't understand is how they "decide" which ones are staying and which are going. Do the same birds migrate every year? Do the baby birds learn whether to migrate or not from their parents? Do migratory birds mate with non-migratory birds, or do they stay separate? And if they do stay separate, does that mean they're on their way to speciation here?

Just curious. I doubt I'll ever find out. Oh well, I still like the huge flocks of grackles. I know most people hate them, but for some reason I find them kind of exciting. It's part of the whole holiday shopping experience to me, because they like shopping mall parking lots so much. It's like Christmas shopping wouldn't be Christmas shopping without all the wreaths and lights everywhere, the sound of Salvation Army bell-ringers at the front entrance, and your car covered in grackles when you come out.

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