Wednesday, December 24, 2014

The Downy Woodpecker

Several days ago I bought a new 300mm telephoto lens. I've been eager to try it out, and December 21st was just the day to do so. I traveled out to a few local parks, including the newer Mary Virginia Crites-Hannan Park right outside of Circleville in Pickaway County. Although a smaller park, there's a decent patch of second-growth forest and a nice prairie they planted about four or five years ago. It's a really birdy park too, which brings me to the subject of this post. There were at least two Downy Woodpeckers in the small area I explored and I was able to get a few photos of them.

Downy Woodpecker
Downy Woodpeckers, Picoides pubescens, are probably the most common woodpecker species in the United States. They can essentially be found from coast to coast and everywhere in between, aside from some desert regions like western Texas, Arizona, and smaller parts of southern California and Nevada. They inhabit a range of forest types and even open areas where they will feed upon insects found on small herbaceous plants. Downy Woodpeckers are nearly identical to the Hairy Woodpecker, but there are a few differences to look for in the field. A big one is the size; Downy's are only about 2/3 of the size of a Hairy. Another is beak length; a Hairy Woodpecker's beak is about the same length as its head, but a Downy's beak is much smaller (as you can see above). You can read about some of the other differences here. In Ohio, when you come across a Downy/Hairy woodpecker, it's much more likely to be a Downy. Hairy's are not rare by any means though.

Downy Woodpecker Ohio

Woodpeckers are well-adapted to their bark-clinging lifestyles. If you look at the photo above, you can see a Downy's large feet with large, curved claws; this helps with clinging to bark. Woodpeckers are also a bit different from other terrestrial birds. Most terrestrial birds have feet with three toes facing forward and one toe facing backward; this arrangement is known as anisodactyl feet. Essentially all woodpeckers have zygodactyl feet, which is where two toes face forward and two face backward. This arrangement also helps woodpeckers cling to bark better. Woodpeckers also use their tail to brace themselves as they cling to bark. If you look at the previous photo, you can see this in use; the tail is pushed down against the branch in order to help stabilize the woodpecker. A woodpecker's tail is made up of very stiff feathers, and these feathers are attached to large muscles which allow for a range of fine muscle control. If you've ever seen a woodpecker climb up a tree, you've probably noticed that it climbs in short, jerky bursts instead of one fluid motion. Woodpeckers actually climb by using their feet and tail. A woodpecker will lean close to the bark, which takes pressure off the tail, and then push straight up with their legs. They will then swing their legs up quickly and grab the bark once more before bringing their tail down to stabilize everything. They will repeat this method to ascend a tree, which gives them their jerky climbing appearance.

Downy Woodpecker Ohio
While on the trail, I found another Downy on a large, dead tree. I quickly noticed it was a female Downy Woodpecker since it lacked the red found on the males' heads (which can be seen on the two previous photos). She was standing in one place and excavating a cavity. I first thought that she was excavating a nesting cavity (all woodpeckers are cavity nesters), but it seemed a little early for that. I looked around on the internet and my suspicions were confirmed; Downy Woodpeckers begin excavating their nest cavities in mid April and May. So what was this one doing?

Downy Woodpecker Excavating
It turns out that Downy Woodpeckers not only nest in cavities, but they also roost in cavities. While they mainly excavate roost cavities in the Fall, they will also do it whenever they need to. I'm assuming that this is the case for this individual. A Downy's roost cavity is built a bit differently from their nest cavity. The main difference is the depth of the cavity; a nest cavity is deeper than a simple roosting cavity. Roost cavities are also built to hold a single individual, instead of a bunch of hatchlings.

Downy Woodpecker Excavating
I stood around for awhile and watched as she worked on the cavity. Eventually she took off, probably to forage for some food.

I haven't had many bird-related posts on this blog, but that has started to change in the past month. I'm a bird-guy first and foremost, but I haven't been able to get any decent photos with the lenses that I had. With my new 300mm lens, I should have more opportunities to get some photos, and hopefully that means more bird posts, so keep on the lookout!

2 comments:

  1. Awesome pictures Kyle, and very informative on woodpeckers, they are such a cool group! #piciformes

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