Chris’ Eastern Screech Owl Nest Box Cam’

The 2004 eastern screech owl (Megascops asio, formerly Otus asio) nesting season has concluded in this urban Austin, Texas, nest box.

The views shown here are 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 normal daylight that streams in through the entrance hole, but the extreme lighting contrast between the portions of the interior that are in direct sunlight, and the dark floor of the box where most of the action takes place, can make it difficult for the cameras to produce high quality images. At night, however, arrays of infrared illuminators take over from the sun and the entire interior is consistently illuminated and clearly visible. (Meet the nest box internals.) So, the best viewing is at night. Since the owls are nocturnal, that seems acceptable.

Daily Image Archive

March 2004
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April 2004
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May 2004
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First Hatchling: April 6  •  Eggs Hatched: 4 of 4  •  Surviving Nestlings: 3 of 4  •  All Out of Nest: May 4

Daily News

July 12 - Shortly after sunset I was surprised to encounter a pair of young screech owls, and their adult escort. The youngsters were investigating the area around the nest box tree, and one had a quick look inside the box. I studied their legs looking for bands, but even with the aid of a light, I couldn't satisfy myself that bands were present; also can't be sure that they weren't. More likely than not, however, they were this year's owlets.

May 13 - Repeated owl sightings, both pre-dawn and post-sunset, including two owlets, and both adults.

Given that they are moving between perches and trees, the owlets must be flying to some extent. They never do it while I watch, of course. Usually, they vanish from one perch, or appear on another, when I glance away for a moment. One thing that is clear is that flights are still short, and painstakingly planned. Launch speeds and landing places are carefully considered for a minutes at a time before any attempt is made. Flights are anything but spontaneous actions during this early learning period.

May 10 - ≅10 PM - Found both owlets perched together in one of the hackberry trees. When the adults arrived, they clacked their beaks at me, but eventually decided it was more important to hunt than to watch boring, old me. They may think me a pest, but it seems they don't really believe in their hearts that I'm dangerous. You'll note that one owlet appears significantly larger than the other. That may be the result of reverse sexual size dimorphism, the $10 phrase meaning that females, on average, are larger than males in this species. Put another way, the big fledgling in back is most likely to be a female, and the smaller one in front is likely to be a male.

≅3 AM - Warning clacks from one of the adult owls told me the owlets were still nearby. A search of the nest box tree and the several nearby trees turned-up both adults and two owlets. The owlets were, once again, in the big hackberry trees at the back of the yard, and the adults were following me around to make sure I didn't cause any trouble. The adults are very wary but vastly less aggressive than they were last week; even standing beneath an owlet earned me only warning bill clacks. Presumably, they know the owlets are now mobile enough that they can get out of the way of most threats.

May 8 - Around 4:30 AM, I caught sight of one of the owlets in one of the pair of intermeshed hackberry trees at the back of my yard. Together, they provide a lot of good hiding places, so the owlets may be roosting there for the time being. If so, at least one of the adults will be roosting nearby, on guard duty. However, I couldn't catch sight of any owls, young or old, during the day. If they were roosting in my yard, they found good hiding places.

May 7 - 2:30 AM - Spotted an owlet high in a hackberry tree at the back of my yard. They must have some ability to fly, already. Usually the adults calm down when the owlets start flying, so it may be that they haven't much confidence in the youngsters' skills (or judgement?), yet. I couldn't find any other owlets, but they now have a lot more room into which to spread out, so they'll be harder than ever to locate. Note that the fledgling must not be the least bit concerned about falling, because he's not bothering to use his talons to hold onto the branch.

May 6 - At 5:18 AM I located two owlets in the nest box tree, as well as a pair of defensive adults. A search around noon turned-up nothing. After sunset the adults continued their defense of the nest box tree, and were particularly interested in defending an area near two large hackberry trees at the back of my yard, not far from the nest box tree. So, the owlets are certainly in one or more of those trees.

May 5 - A search of the nest box tree by daylight turned-up two owlets, and an adult sitting guard duty very nearby. I continue to hope that I'll spot a third owlet. As you can see, they try hard not be noticed. An attempt at owlet counting this evening turned-up highly defensive adults, who prevented me from making a thorough visual search of the tree, but the presense of defensive adults means that there are owlets there to be defended, so the adults are good news. By the way, when owlets leave the nest, they go from being "nestlings", to "branchers". In a week or so, when they've learned how to fly, they'll be "fledglings".

May 4 - To my great surprise, the owlets all left one after the other around 8:45 PM. I try to be around when owlets leave the nest, and was heading home at the time, just in case one would leave tonight (I was pretty sure none would), but was still about five minutes away when they all made their break for freedom, so I don't know as much as I'd like to. I have located two of them hidden in the outer branches of the nest box tree, within a few feet of each other. (The photo shows the owlet that was easiest to find.) I expect that the third owlet is in there somewhere, too, but even better hidden. I have checked all the bad places fallen owlets have chosen to climb to in years past, and every other place in the area that I can think of, and the third owlet isn't in any of them. That's good news, and reinforces my belief that he's safe. Photos and updates will continue as opportunities present themselves over the next week. The adults are on full alert, and have already attacked me once during my owlet search, which is as it should be.

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 need to ask questions, continue to send email.

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