Archive for the ‘Know Your Icterids’ Category

Bronzed Cowbird in Winter

Saturday, December 20th, 2008

I thought this was interesting: the Bronzed Cowbird is on the edge of its winter range, more or less, so its prevalence at Welder might conceivably be affected by warming. I wonder what the Christmas counts in Texas will show for the bird.

This shot was taken by eyes23blue at 6:27 am on December 15:

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Update: Here’s a graph from CONE Welder (much of which still works, making this a good time to probe through the data and images for interesting nuggets) showing classifications of Bronzed Cowbird by day since the camera went live. We’ve had at least one individual hanging around since early August, but I don’t know how unusual that is for Welder.

Craig’s Leucistic Blackbird

Saturday, November 22nd, 2008

Craig posted some cool shots on his blog today of what I believe is a leucistic male Brewer’s Blackbird:

He took the photo today outside the Craigslist offices, which I believe are in San Francisco. I did a quick googling for “leucistic Brewer’s Blackbird”, and it turned up this really interesting image uploaded by Flickr user Robinsegg on September 28:

I don’t know where or when that second photo was taken, but it looks similar-enough to Craig’s bird to make me wonder: could these actually be the same bird? The pattern of white feathers is not exactly the same; Craig’s bird has some white feathers on the upper back that the Robinsegg bird doesn’t. But it seems just possible to me that that could be the result of the bird undergoing a partial molt during the time between the two photos being taken. And there are a couple of really striking similarities: both birds have a patch of brown feathers toward the back of the crown, and both have what looks like a large white feather in the flight feathers of the left wing. On the Robinsegg bird, it looks like it’s one of the left tertials (or maybe a secondary?), while on Craig’s bird it looks more like a primary. Though I suppose it’s possible that it’s actually a new primary, just growing in, in the Robinsegg photo.

In truth, I think they’re probably different birds that just happen to look similar. But wouldn’t it be cool if they really were the same individual?

Common Grackle!

Saturday, October 4th, 2008

With the change of the seasons, we’re getting some new birds at CONE Welder, including the game’s first official Common Grackle. This photo, taken October 1 by birdbrain, was the first shot to be officially ID’d:

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There have been a number of shots since then (some misidentified as Great-tailed Grackle). My favorite image of the bird so far is this (currently unidentified) one, taken October 1 by txbird:

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I look forward to seeing one of these with the camera myself. 🙂

Know Your Icterids, Part Three: Brown-headed Cowbird

Saturday, May 24th, 2008

After Red-winged Blackbirds, Brown-headed Cowbirds are probably the most commonly seen birds in the birdcam; they’re pretty much always around. As with other icterids, the males and females are quite different. Males are black with a distinctive brown head, while females, which are similar in shape but just a tad smaller, are tan with few distinct markings.

I took these three cowbird shots this morning because I thought it was interesting how the male toward the top of the frame was posturing; he did this several times. (The male at the bottom of the frame shows a more-typical cowbird posture.) The female, too, seemed to be acting unusual, crouching down the way you see in these images. I wondered if this was courtship behavior, but no actual mating took place that I noticed.

Brown-headed Cowbirds are nest parasites, as most readers of this blog probably already know. They don’t build a nest or rear their own young; instead, the female lays an egg in the nest of some other perching bird. I’ve read that as it matures, the young cowbird will often grow larger and faster than its nestmates, pushing them out of the nest to monopolize the attentions of its foster parents.

The Wikipedia article on the Brown-headed Cowbird currently includes the following photo, taken by Frankie Rose, showing a Brown-headed Cowbird egg in the nest of an Eastern Phoebe:

According to that Wikipedia article, the cowbird’s nest parasitism evolved as an adaptation to the bird’s traditional lifestyle following the North American bison herds. With the arrival of European settlers and their livestock, they found themselves admirably adapted to the new conditions, and have continued quite successfully (in the eyes of some, a little too successfully) to this day.

Know Your Icterids, Part Two: Bronzed Cowbird

Friday, May 23rd, 2008

A bird that’s new for me with CONE Welder is the Bronzed Cowbird. Like the other icterids in the system, the males and females look somewhat different, though with the Bronzed Cowbird the difference isn’t as obvious as it is with the other icterids we’ve been seeing.

Here’s a shot of a male that I took today:

And here’s a shot of a female I took a few minutes later:

The female has the same pattern of black on the head and back, with lighter plumage below that, though the female is more drab than the male.

As with many icterids, eye color is an important field mark for the Bronzed Cowbird. Both sexes have a really striking reddish iris; birdbrain got this great shot of a male glaring at the camera on May 16:

Something that confused me the first few times I saw these birds was that they don’t always show the puffed-up head and shoulders that Sibley shows in his illustration (he calls it a “ruff”). They do show it a lot, though, as in that photo of the male at the top of this post, and in this cool shot taken by txbird on May 10:

Finally, here’s a good comparison shot I got back on May 4. I think this shows a male Bronzed Cowbird in the middle, with a female on either side. (I’m not sure about the identity of the other two birds in the background.) Besides the difference in their markings, you can see that there’s a bit of a size difference between the sexes, too; the male is a little larger.

Know Your Icterids, Part One: Red-winged Blackbird

Friday, May 16th, 2008

Blackbirds and grackles feature prominently in the birds we see in the CONE Welder camera. They’re pretty straightforward from an identification standpoint, but it’s important to realize that the males and females look quite different from each other. There are four icterid species that we see a lot of in the game currently, but to a casual observer they can look like eight different kinds of birds (at least).

Some of us were chatting in the game the other day about how few of the female Red-winged Blackbirds were being successfully identified. I remember how, when I was twelve and visiting Florida for the first time, I spent days wondering what those “sparrows” were that were always hanging around with the Red-winged Blackbirds. It wasn’t until I looked at my grandmother’s field guide that I realized they were actually female blackbirds.

Here are some shots of female Red-winged Blackbirds taken in the last few days. These are by users rafa, achadamaia, and avatar99, respectively:

They’re superficially sparrow-like in terms of color and markings, but that long blackbird beak is a dead giveaway.

Even the male Red-winged Blackbirds can be confusing at times. When they flash their epaulettes they’re easy, of course, as in this beautiful shot by txbird that I posted the other day:

But they can hide and reveal those shoulder patches. When they cover up there’s often only a narrow strip to help identify them, as in this shot by whereismyrobot:

There’s still another look that Red-winged Blackbirds can have; check out this shot of an immature male taken by widget:

Don’t look down your nose at those Red-winged Blackbirds just because they’re always around. They’re more interesting to look at than you might think. 🙂