Naturespeak A naturalist's view of the world

January 28, 2009

Owl Things Considered

Filed under: Uncategorized — wykes @ 11:02 pm

I’ve just finished up with a four owl week. During this late January period of frigid three-dog nights, experiencing a couple of two-owl days ain’t bad. But, when you can put a few of these multi-owl days together and come out with a four owler, well, that’s something. Some would classify my effort as a mere two-hooter happening, since two of the four owls of which I speak were either dead or not present at the time of their “discovery.”  To those naysayers out there, however,  I will boldly say “frankly, my dear, I don’t give a hoot.” This thing is about the birds, not the man.

My first encounter was with a Saw-whet Owl. Well, O.K., I didn’t actually see one of these soup can sized birds but I found one of their snow angels – I think.  Take a look at this picture (here) and you’ll see what I’m talking about. My identification is based on size, proportion, and something else which I’ve since forgotten. Anyway, these tiny owls feed on song-birds and mice during their winter stay. The songbirds are as vulnerable as ever, but the mice are able to get about under the protective white stuff with relative impunity. They are, to put it bluntly, loving it. Aerial predators, such Saw-Whets can’t see them but they can hear them them through the snow (when mice burp, owls listen!). I believe this track shows where one of the owls plunged directly down into the snow at the base of a Queen Anne’s Lace to nab an over-confident and chatty little rodent at its base. The wingspan mark, measuring around 17 inches, combined with the short tail mark point to this species as the maker. I can’t tell you if the plunge was successful other than it successfully produced an nice little snow angel.

The subject of Screech Owls came up while listening to a morning report on NPR a few days ago. Obviously lacking any solid new to report, the local station aired a short segment on how Screech Owls are suffering through this winter. The deep snow, they report, is keeping them from their food and they are suffering – you can hear their painful hunger-driven screeching ringing through the night woods. A well meaning commentator, when asked about this situation, suggested that people put out bird seed to help. I heard my wife laugh from down the hall when this comment aired.  I’m sure he meant that the seed would attract mice and birds which, in turn, could be eaten by the owls, but there was no real science to back up this claim.

With visions of screech owls lining up at feeders throughout the north country, I headed off to work that morning thinking about the reality of the claim. The best thing to do would be to verify the presence of dead screech owls and examine them for signs of starvation. No sooner had that thought entered my head than I spotted a dead screech owl a block from my house! The bird was dead on the road – the victim of a car strike – but the circumstance was a bit spooky. I retrieved it and performed a little bit of science on it. This bird, an ashy salt & pepper gray phase individual, was not starving at the time it met its untimely end. Its breast muscles were plump and full up to the keel. I suppose it could have been heading for the nearest feeder, now that I think about it.

Detailed examination of the bird revealed a 19 1/2 inch wingspan which provides a comparison with the smaller span of the Saw-Whet mentioned earlier. I spread the feathers out in order to get a good look at the silencers on the wings. The leading edge of their primary (wing) feathers have a comb-like structure which evens out, and therefore silences, the rush of air over the wing (see here). All owls, at least the night-time fliers,  have this stealth feature. All owls are also equipped with impressive talons. Even tiny owls like the Screech, have formidable talons and rough-padded feet for securing and killing prey… such as feeder birds, for instance (see here).

My third owl was not only alive, but it was in the midst of performing one of the truly remarkable rituals of the natural world. The bird was a Great-horned Owl and she was sitting on eggs.  Great-horns begin their courtship in early winter and lay their eggs by late January or early February. By doing so, they beat everyone else to the punch kinda like a baseball fan camping out at the stadium while snow is still piled high on the seats.

Great-horned Owls take over the old nests of Red-tailed Hawks , Herons, and even Bald Eagles long before these birds would even think about nesting. By the time the original nest makers return they find their nest occupied and will move on to make another nest. This particular owl opted out of the nest stealing game and decided to situate herself in the cavity of an old cottonwood snag (see here). The snow downwind from the tree had several downy feathers scattered over the surface (see here).  A closer look (see below) shows her sitting hen-like on the nest.  This a very non-owl like pose although it is made significantly more owlish by those intense yellow eyes. The impact of this scene is made especially poignant when you consider that the overnight temperature just previous to this shot was -1 degree F and the daytime temp was hovering at 12 degrees F. She will go through much more of this in the coming month before her young finally hatch.

My last owl of concern was a Long-eared Owl. These wintering birds are creatures of habit who tend to return to the same daytime roost day after day. They prefer the cover of dense  tangled vegetation or conifer trees. Often they roost together in informal groups and it is not unheard of to find up to 20 owls in the same tree. I believe the proper way to refer to such a gathering as a parliament. My bird (someone else found it and told me about it, so it’s not really mine – but then again it’s not really theirs either) was a solitary member of the House of Commons.

He was alone and somewhat contented when first approached (see here). Squint-eyed and upright, with “ear tufts” erect, he was the near-perfect imitation of a stick. You can see why they can be so hard to spot when employing such camouflage. My presence irritated him for some reason (this happens in my presence quite often) and he began to puff up into a defensive display (see the photo at the top of this entry). With those intense yellow eyes burning a hole right into my soul, the bird raised every feather of it’s body and dropped a wing down. Overall, the act served to enlarge the owl to nearly three times it’s starting size (see below). “Look at me -ain’t I frightful” is the intended message which is reserved for potential predators. Owls have on their back bigger owls to bite ’em, you see, so a good defensive act is always a good backup.

This was my signal to back off.  I didn’t want to flush him just for the sake of a picture. By the time I was ready to turn around, the Long-ear was in full puff mode. He started to blink continuously and look nervously about. My last photo caught him in mid blink and it is the best shot of the four owl week (see here). A translucent nictitating membrane, which serves to cleanse the surface of the eye, is employed from the upper inner corner of each eye. It is a serendipitous occasion to catch this motion in mid-wipe.

Owls are, in fact, serendipitous creatures who don’t allow too many viewing opportunities.   This is why a four owl week is not something that can be expected on a regular basis. Every view has the potential to be a learning experience. There is actually a potential to have a five or six owl week in these parts, so you can bet owl give it a try.

3 Comments »

  1. This is all so interesting. Is the owl on the eggs sitting henlike because of the extreme cold? I would have guessed they’d crouch on their eggs more uprightly, like penguins. Also, the snow angel shot and the mid-blink shot are great. I’ve asked this before, but how/where did you learn so much about nature? I know something about plants, but would love to learn more about animals… but the books I read don’t detail such interesting things as you do in this blog.

    Comment by Monica — January 31, 2009 @ 12:48 pm

  2. Very interesting account. If theres a cluster of conifers close to a well established bird feeder, I usually check for pellets. I’ve found a number of winter Saw-whets this way. I love the image of the GHOW on her nest.

    Comment by Michael — January 31, 2009 @ 7:12 pm

  3. Monica:
    The owl’s horizontal pose is normal – they incubate their eggs just like a chicken does. They may sit tighter when it’s cold, but otherwise it makes no difference.
    In answer to your “how do I know” question, I actually make things up as I go! No, not really. I have an educational background in wildlife biology and decades of field experience. That training allows me to narrow down the subject at hand and enables me to use the right terminology when researching my subjects. My research, with books, direct observation, and internet, allows me fill in my gaps. Sounds rather heady, I know, but you did ask.
    Gerry

    Comment by Gerry Wykes — January 31, 2009 @ 10:42 pm

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