Chris’ Eastern Screech Owl Nest Box Cam’

The 2005 eastern screech owl (Megascops asio, formerly Otus asio) nesting season has concluded in this urban Austin, Texas, nest box.

The views shown here were provided by one or more tiny monochrome video cameras that are sensitive to both visible and near-infrared light. During the day, the camera "sees" using the daylight that streams in through the entrance hole. At night, arrays of infrared illuminators take over from the sun. (Meet the nest box internals.)

Daily Image Archive

March 2005
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May 2005
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Owlets Out of Nest: 4 of 4 • Eggs Hatched: 4 of 4 • First Egg: March 5

Daily News

May 9 - 10:00 PM - Both adult owls arrived to keep an eye on me while I walked beneath the hackberry trees with a light, looking for owlets. I wasn't attacked by the male, which makes a change, so I believe that the owlets have begun flying (it's about that time), which takes the adults off of high alert. I also conclude from this that the fledglings are no longer in my yard. They're probably located nearby, however, or the adults wouldn't have taken an interest in me. The only bad new is that now that the owlets are mobile, sightings will be hard to come by.

Thanks to Emily F. & Fred H. for their postcard, and to Chuck D. for his! Also thanks to Gerry Gomez Pearlberg for the copy of her book!

By the way, I think I'm just about caught up on my owl-related email. I've been answering the messages that asked questions, and just reading the remainder. Undoubtedly, some messages must have fallen through the proverbial cracks, however. Sorry about that. In any case, thanks for all of the kind words.

May 8 - Bad news: One of the owlets died today. This afternoon I went out after the rain had cleared just to have a quick look in the trees for owls, and found an owlet face down in some grass beneath the nest box tree. It turned out to be alive, but wet, and lethargic. I took him to Sallie, my friend who is an expert raptor rehabilitator, and had her take a look at him/her. He had no obvious sign of injury, and after being carefully blown dry he perked up enough to take water and a little food. Unfortunately, he must have already been exhausted by his ordeal beyond his ability to recover, and he soon died. My best guess about what happened to him is that he was knocked out of the nest box tree by the thunderstorms that passed through our area beginning late on the seventh. From there he doesn't seem to have had the strength to get up and return to the tree, so I assume he had already lost a lot of energy to being cold and wet, and hanging-on during the storm. Sallie found he weighed 100 grams, where an owlet his age should have been about 120, so while he wasn't starving, he hadn't received all the food he could have used. That would have left him with less strength and energy than he ideally would have had to help him cope with a situation like this. Also, he had a small hernia on his belly where the yolk sack had attached to him in the egg (the equivalent of the belly-button in humans). Hernias like that become fatal if a portion of the intestines expand into them and thereby become kinked or otherwise obstructed. That does not appear to have happened in this case, however. All things being equal, he could probably have survived with it.

Needless to say, I was sad to have this happen. However, the first-year mortality rates for birds of prey are very high, so losses are to be expected.

On the plus side, there will be more food and supervision available to the surviving owlets. As sightings occur, I'll update this site.

May 7 - 4:30 PM - After a very long search, I found both adults and an absolute minimum of three owlets. Four, maybe. Three, definitely. One of the owlets is still in the nest box tree. This would be one of the two that left the nest box on the 5th, probably the youngest. Two of the owlets had tried to move into the pair of very large hackberry trees at the back of my yard. Unfortunately, they must have both fallen short in their attempts, and both landed in, or climbed into, a lantana bush. I don't know how many times I walked past that bush while staring up into the trees searching for the owlets, all the time under the watchfull gaze of both adults (and both owlets, for that matter). Anyway, once I finally noticed them there, six feet from where I was standing, I set about moving them to the limb of the hackberry tree on which their mother was concealed amongst the outer leaves. They resented being handled, but were reasonably calm about the whole thing. After they were both on the limb, and I had retreated to a decent distance, the first owlet walked right up the limb, making little, flapping leaps over twigs in the way, and soon disappeared into the outer branches. The other owlet stayed-put a lot longer, and when he/she did start climbing, he came to the first little clump of leaf-bearing twigs sprouting from the limb and stopped there. I suppose his instincts told him to hide amongst the first leaves he came to, and those where them. I spent a lot of time standing very nearby him, photographing him, and the possible fourth owlet, but even my proximity and chatter did nothing to convince him that his little tuft of leaves was anything less than sufficient cover. Short of getting out a ladder and going after him, there wasn't any more I could do, so that's where I left him. He's under the protection of both of his folks, however, so he should be fine, and he can always decide to climb later, now that I'm out of the way.

Thanks to Marianne C., Gary D., Margaret H., Tom & Peny, and Cheryl G. for the postcards!

May 5 - 11:10 PM - Owlet no. 4 still on the rail.

10:18 PM - Owlet no. 4 still on the rail. That's a perfectly good place for an owlet, provided he/she moves on before sunrise.

9:20 PM - Owlets 3 and 4 are out of the nest box. No. 3 has already leapt to a tree limb, and walked off into the tree canopy. No. 4 is still sitting on the rail deciding what to do. I had been out keeping an eye on him, but gave up after concluding that he wasn't going to do anything while I was watching.

May 4 - Same as yesterday; still two owlets to go. From what I've seen, I believe the adults have begun reducing food deliveries to the nest box in order to encourage the owlets to leave. They don't seem to have received the message, however. It's easy to understand why the youngest might be holding back, being three days younger than owlet no. 3, but that leaves no. 3's reticence a bit of mystery. It could be that the two older siblings were sufficiently more successful in competing for food that they developed even faster than their age differences would suggest, leaving the two youngest with some catching-up to do.

Thanks to Mariann C.A. for the postcard!

May 3 - Two down. Two to go. Still. Put another way, neither of the owlets remaining in the nest box chose to leave today, which is a divergence from the ideal schedule, but try telling the owlets. The adults continue reasonably routine food deliveries to the nest box, so they aren't making any particular effort to encourage the owlets to leave. For myself, persistent sleep deprivation has begun to loose its charm after nearly two months (as usual), so I've been encouraging the owlets all I can. Unfortunately, extolling the virtues of the outside world to the owlets on my TV is having no obvious effect.

Thanks to Mark I., Susan, Gary D. (thrice), Anne H., and Jewell T. for their postcards!

May 2 - At 12:23 AM, the first owlet left the nest box. He appears to have ended-up on the ground at the base of the nest box tree, and has climbed up the trunk to (relative) safety. I'd like to see him another 10 or 20 feet up, but he's not going to move while I'm around, and his parents aren't going to tolerate me getting out a ladder, grabbing him, and placing him higher-up in the tree. But with both adults on high alert, he should be OK. Here he/she is as of 1:39 AM.

3:19 AM - The owlet that left the nest box has climbed high into the nest box tree where its safety is assured.

8:14 PM - Owlet no. 2 exited the nest box four minutes after sunset and began climbing high into the canopy of the nest box tree. After stepping out onto the owlet rail, he/she spent five minutes or so sizing up the situation in the fading light. Having made up his mind, he then walked over to the stick extending back from one end of the owlet rail, walked along it a short distance, which took him slightly around the side of the nest box, then leapt to a major limb of the nest box tree which rises slightly behind and off to the side of the limb on which the nest box is mounted. He then began climbing up that limb, leapt to another limb, then another, met up with one of the adults who gave him a small food item, then he was climbing again, leapt to yet another limb, and then he headed up toward the highest outer canopy of the tree, where I lost sight of him. This was my first opportunity to get a good look at an owlet as it climbed a tree, and I must say I was impressed. He was fearless, quick, sure, and strong. Even dealing with substantially vertical limbs, he wasn't so much climbing as fast-walking up them. If the going got at all difficult, he'd flap his wings to keep himself against the tree, and to make it that much easier to lift himself up it.

During the week or so that the owlets are out of the nest, but can't yet fly (they're known as "branchers" during this time), the adults are on maximum alert. During the day, at least one of them sits with the owelts in the outermost, uppermost branches of the tree, where they try hard not be noticed. Come nightfall, the strategy is different; they won't tolerate anyone getting anywhere near the tree in which the owlets are sitting, and they try not to be away for long while hunting. When the adults see, or more probably hear, something approaching the owlet tree, they fly to a perch from which they can watch the intruder and issue vocal warnings. If that doesn't dissuade the interloper, they will dive down at it, whooshing past it just an inch or two from making contact. If that doesn't unnerve the invader, they repeat the high speed dives past it, but they hit it with their needle-sharp talons as they go by. So, for anything to get anywhere near the owlets, it would have to be incredibly stealthy and lucky, or indifferent to pain and extremely determined.

Meanwhile, the two owlets remaining in the nest box continue to receive food deliveries, and, when hungry, they fight one another for the opportunity to sit in the entryway and monopolize those deliveries.

Things to Know About

If you are enjoying the Eastern Screech Owl Nest Box Cam' this season, please send a picture postcard from where you live. My address is: Chris W. Johnson, P.O. Box 302042, Austin, TX 78703, USA. If you have questions, continue to send email.

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