September Quiz Answer

To refresh your memory, here is the photo from September’s Bird Quiz. The bird was seen in Colorado during the month of August. Don’t read any further if you want one last chance to identify this bird.

09 LakeManitou-CO_LAH_1981

I’ll tell you at the start that we usually see these birds in the air, not perched on a twig and easily examined. I have a much harder time identifying these birds in flight, so I was quick to nab this shot when the opportunity presented itself!

So, what kind of bird do we have here? Again, it’s clearly one from the back half of the book—a perching, or passerine, songbird. These members of the order Passeriformes make up more than half of all birds. They share a common foot—three toes pointing forward and one toe pointing backward—which helps them grip their perch. If you’ve ever had a pet bird, you’ve gotten a good look at this handy arrangement. And while other kinds of birds make sounds (some more lovely than others), the passerines are noted for their melodious serenading.

So, which type of perching songbird is this?

So much of identifying birds is knowing what to look at. Ducks are often the same size and shape, at least at first glance, so we look at color. Shorebirds are largely the same color, especially in the winter, so we look at the beak size and shape, the length and color of the legs, perhaps feeding behavior, and the overall size of the bird.

In this case, I recommend a good look at the wings—do they extend past the bird’s body?  How about the beak—is it wedge-shaped or pointed? Notice the overall shape of the bird—is it round, flat, skinny, or elongated? And of course  note the the color(s) of the feathers—are there wing bars? A ring around the eye? Stripes, speckles, spots?

This bird has long, pointed, protruding wings. They’re a little hard to see with the angle of the photo, but you can see them of you look. They extend past the body and cross at the tips. The beak is short and pointed, perfect for nabbing insects. There’s a faint white line behind the top of the eye. This will be an important field mark. And the formal suit of feathers is a big clue.

There’s one other aspect that you can’t know from this picture. I was standing on a boardwalk next to a lake. And there were a lot of these birds flying around. Swallows love lakes and ponds because of all the flying insects, and these birds were doing their part in keeping the mosquitoes in check.  If you had watched them with me, as they soared, wheeled, and swooped, you’d have no doubt that you were watching a flock of busy swallows.

Identifying a bird as a swallow is relatively easy. The only similar birds are the swifts. But swifts don’t land on twigs. The only time they stop is to nest or sleep hanging on vertical surfaces such as sheltered cliffs (and caves), or inside chimneys or hollow trees. Swifts are stockier (a friend describes them as flying cigars), and their flight isn’t as graceful as a swallow’s.

The tricky part is to figure out which swallow this is. If you look in a field guide, you’ll note that most swallows, like our bird, keep to the dark and light color scheme. The exceptions include Cliff Swallows, nearly black Purple Martins and colorful Barn Swallows. The latter two species are the only ones found in Colorado that have forked “swallow tails” so we can easily eliminate them. Depending on the lighting, the colors of the other species may not be clearly visible. And then there are the drab females and immature youngsters.

Our bird is white and a charcoal/brown. We can easily see that the area from the beak down is white. Bank Swallows have a “bow tie” (they have to dress up to work at the bank) so we can cross them off. Northern Rough-winged Swallows look as if their chins and necks need a good washing. Yes, there’s a brown cast to the top of the chest, but on a Rough-wing that would be much darker.

Where does that leave us? Tree and Violet-green Swallows are very similar. Both were present when I took photo, and this could be either one. If it was flying we could look for the “saddle bags” that mark the Violet-greens, but this bird is perched. Young birds of both species have that gray-brown smudgy area on their chests.

Let’s come back to that white line above/behind the eye. A look at a picture of an adult male Violet-green Swallow shows a white semi-circle around the back of the eye that the Tree Swallow lacks. In the female, this shows up as a faint eye-ring—more a patch with the eye in the middle. But in the juveniles, we get the same eyebrow we see here. I strongly suspect that this is a Violet-green Swallow.

Here is another picture of a young Violet-green Swallow, with a young Tree Swallow and a young or female Bank Swallow for comparison.

 

Advertisements
This entry was posted in Bird ID Quiz and tagged , , , , , . Bookmark the permalink.

One Response to September Quiz Answer

  1. Oops, I guessed wrong (tree swallow). But you make it so interesting to think this through. Thank you. Best, Tanja

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s