I Fledge Allegiance

At 8:10pm tonight, the first owlet stepped up to the window, got first one, then two feet out, looked around, and flew off into the trees next to the box. All of this took 40 seconds, although he had earlier spent a good amount of time in the window before dusk set it. He actually hovered for a second or two as he looked for a place to land. Other fledging flights we have seen in the past have been more direct downward glides. This one has been in the box an extra 2 or 3 days beyond the average, and has probably developed his flight muscles and feathers to the degree that he is capable of slightly more sustained flying. He will still spend most of his time walking in the branches for the next part of his life, but he has achieved freedom from the box.
Meanwhile, back in the box, there have been no feedings as of 9:45 pm, so the parents seem to be either starving them as inducement to leave, or focusing their attention on the first fledgling (or both of the above.)
Early dusk is the normal fledging time we have seen in the past, although last year we did have 2 owlets fledge on the same night, with the second one being closer to 10pm. But in that case, he was the last of 4 to leave, so was probably quite ready to be out of the box. This year, due to the bee incident the box material isn't smelly and full of poop and bone fragments. We have always thought that ought to be a strong incentive to leave on time.
We found one of the parents vigilantly watching the whole thing in the bush just behind the nest tree. We also heard a Barred Owl not far from our property shortly after the fledging, so this added a bit of nervous tension to the evening. (Barred Owls are much bigger, and predate on Screech Owls, among other birds, rodents, etc.)
We'll keep an eye on what the other two do.

Getting Ready to Go

We thought one of the owlets would go tonight. He sat in the entrance for a good while at dusk, with his feet perched on the outside rim of the hole. He looked down, up, and all around, getting a good look at his surroundings. But in the end, two successive feeding parents came, and he stepped back inside, seemingly having decided that another night of food inside the box was a good idea. Shortly afterwards, there was quite a scramble inside the box for position near the door. But later all three settled down on the box floor, content to just wait for what was to come.

According to Gehlbach, owlets lose a bit of weight in the last week or so in the box. He speculates that this may be due to less food being available later in the season, but also because parents may withhold food in order to encourage fledging.

We hope they choose to fledge soon. They are definitely due, as the average is around 26-30 days (27.7 +/- 1.8 for you statistical types). It's time for the next stage of their lives to begin!

Getting Ready

Lots of time this evening spent contemplating the outside world. In one photo you can see the parent visiting with food. These were taken with a long lens from our deck. Fledging is likely within a day or two, usually around dusk.

Day in the Life

I've put together a time-lapse video of yesterday (May 23, 2009) in the owlets' life:

This looks like non-stop action, but in reality, there are some long periods with no action. The motion detector software doesn't capture these, so it looks more frantic than it is. But it gives a little peek into what they do all day, from midnight to midnight.

One day I'll have time to learn how to slow down the action during feedings so they can be seen better, but this is a start.

In case you missed it, here's a video from when they were younger. This one has an audio track and annotations of what's going on:


Enjoy.

Stretching

Yesterday was a day for the owlets to do a lot of stretching and climbing. At times they hung their heads down in a comical fashion as they dozed. They stretched wings, stood up tall, and at several points, all three of them were up on the railings and off the floor. They are taking short stints in the doorway, looking out at the world. These are the first owlets we've had that have actually seen the world in a dramatic way before leaving the box voluntarily. We can only speculate what they must think of it all, and what they must think of people.

A bit of lizard tail hanging out of the mouth.

Happy Together

The littlest owlet came home from the opthalmologist with a clean bill of health. The eyelid still has some swelling, but the eye is fine. So, we got him home in time for the evening feeding. All three are eagerly awaiting meals. Early on in the evening, one or the other of the owlets waited in the doorway to guarantee receipt of the food. When food arrived, the owlet often was pushed backward a bit, but usually held on and didn't fall or lose the advantageous position.

The Vet

Working with our raptor rehabber, we've decided to take the youngest owlet to her, to take in to the veterinary opthalmologist today. He will be back in the box before feeding starts tonight, if all goes well with the eye exam. The eye is open but the lid is still swollen.
The remaining 2 owlets are getting quite acrobatic. One of them even sat in the entranceway for a few minutes.

Open Eyes

The update on the bee saga is that right eyelid of the youngest owlet seems to be reducing its swelling. In the 2nd and 3rd photos, you can see the youngest owlet, which spent most of the evening on the rear railing, has its eyes open. Although it still has its left eye closed a lot of the time, the eye can open, and appears to have a nice pupil and iris. We are still monitoring it to see whether a veterinary opthalmologist needs to be consulted, but if things continue to improve in the next day, we think we're out of the woods.
The other 2 owlets continue to seem normal, although the oldest one still seems to have a swollen cere. We're not worried about it, as the nostrils seem wide open. None of the owlets are displaying any kind of abnormal behavior, being quite active, self-preening, and climbing around on the railings.
Soon, we expect wing-flapping and exercising to begin in earnest, as the owlets will begin to learn how to use their wings in anticipation of their first big flight to the tree branches within a week or so.

Cleanings

Regular watchers of our camera will have noticed the fog that developed over the camera window yesterday. When we cleaned the box during the bee incident, we must have cleaned it inadequately. Today, I went up to clean it. I took the opportunity to check on the owlets, and only one of them now has an eye swollen shut. So, they're on the mend.


I also did a bit of research on the No Pest Strips that killed the bees. They contain a nerve agent, called dichlorvos, that the EPA has considered banning. It is a nerve agent developed around WWII, and has caused birth defects in rodent studies. It can cause lung, eye, and muscle problems, and death. The idea behind it's "safety" is that in low doses, it is much more toxic to insects than to people.

According to OSHA:
1. Effects on Animals: Dichlorvos is an anticholinesterase agent and may cause excessive salivation, eye tearing, sweating, constricted pupils, respiratory distress, anorexia, vomiting, diarrhea, weakness, twitching, paralysis, a slow and irregular heartbeat, convulsions, coma, and death [Hathaway et al. 1991]. Dichlorvos also has reproductive effects and causes malformed offspring in rodents. The acute toxicity of dichlorvos for laboratory animals is significantly high; the dermal LD(50) for rabbits is 107 mg/kg and 80 mg/kg in rats; and the acute oral LD(50) in rats is 25 mg/kg [NIOSH 1995; ACGIH 1991; Sax and Lewis 1989]....
2. Effects on Humans: Dichlorvos is an organophosphorus pesticide and is therefore a cholinesterase inhibitor. Overexposure to this substance causes symptoms that vary by route of exposure. Inhalation causes ocular and respiratory symptoms. Ingestion causes gastrointestinal effects, while skin absorption causes localized sweating and muscle twitching in the area where entry occurred. If exposure is severe, muscle weakness, twitching, fasciculation, and paralysis may occur. Paralysis of the respiratory muscles may cause death. Cardiac irregularities, including complete heart block, may also occur [Hathaway et al. 1991]. Dichlorvos is easily absorbed through the skin, gastrointestinal tract, and lungs because of its high volatility [Parmeggiani 1983].

And according to the New Zealand Environmental Risk Management Authority:

Dichlorvos is also very ecotoxic to aquatic organisms, birds and honeybees.

We decided that as small and fast-growing as the owlets are, it could definitely cause them some problems, so I took down one of the strips in the morning. With no additional bees by 2pm, we knocked down the other strip, and have left them toxic-free.

Bees!!

It started a normal day, like any other in owland. Mrs. Owl spent over an hour in the box in the morning preening the owlets. One of the owlets even made an attempt to get to that interesting doorway where all the comings and goings are. What must that world be like out there?
Well, starting at 1:36, the world began to come to them. For 4 hours bees came in and out, investigating the box, with perhaps 25 or so present at any one time.
Then, suddenly, at 5:40pm, they began to swarm in by the hundreds, exploring the walls, the floor, and eventually clustering on the ceiling. The owlets seemed rather disturbed by all this, but eventually things settled down.
We became very concerned what would happen during the night with all the comings and goings of feeding. We called around to a wildlife rehabber, various beekeepers, and Fred Gehlbach (author of “The Eastern Screech Owl,” the definitive book). The general advice was to get a beekeeper to remove the bees, but the beekeeper we talked to had tried twice already this season with smoke, vacuum, and dust, and neither set of owlets had survived the ordeal. We were also told that there were cases of bees and owls peacefully coexisting, but this didn't seem likely, given the quantity of bees on the ceiling and all the comings and goings related to feeding. So, we took the advice to hang Hot Shot No Pest Strips, which smell foul, have a poison that doesn't harm birds, and was supposed to drive the bees away. We thought this would gradually drive the bees off, as they flew out and chose not to fly back in.
Unfortunately, what began to happen, though, was that the bees began to sicken, and fall to the floor, interacting with the owlets. The owlets began to flick their wings and twitch as if being stung or trying to get the bees off themselves. We called around quickly again, and made the emergency decision to bring the box down and remove the owlets, as the floor was now crawling with bees.
It is always best for baby birds to be raised by their parents if at all possible. So our idea was to clean the bees out of the box, get the owlets a medical checkup, and then return them the same night, or as soon as possible, to the care of their parents.
We gently placed the owlets in a cardboard box filled with wood shavings, and went to our friend Sallie, a raptor rehabilitator. She gave them a thorough checkup. Two of them had been stung on the eyelids, and the eyes were thus swollen shut. The other had been stung on the cere (the flesh that partly covers the bill and nostrils). But they seemed all right, if a bit shell shocked. They spent the whole time out of their nestbox very huddled down, hoping not to be noticed, and seeming very lethargic. But Sallie said they're just terrified, and exhibiting normal defensive behavior.
She then fed them some freshly carved mice to make up for their missing the best feeding part of the evening. She mostly had to open their bills and place it in their mouths directly, because they were so unwilling to move. They did swallow it on their own. She fed them in a box with an older owlet under her care, so he could reassure them with his confident eating behavior.
It is extremely important for owlets to eat whole animal food, bones and all. They need the calcium for their bones to develop properly. Many an owlet hand-raised by non-experts has ended up crippled for life by being fed hamburger or other inappropriate owl foods.
Upon returning home, we cleaned the box, refilled it with wood shavings (never sawdust!), put the owlets back in, and hoisted it back up the tree. Within 20 minutes, the parents began coming with food again. The owlets began acting normal, preening, reaching to take food, and probably happy that the nightmare was over, and the maid service had cleaned the box, to boot. You may notice the clearer view that the camera has.
More photos at Picasa.

Mother

We found Mrs. Owl outside the box this evening. She doesn't spend much time in the box any more, as it is so hot.

We're sorry we haven't had much time to blog and post photos from the box this year. Things have gotten busy, but below is a little selection. The ants are now a constant stream, but they don't seem to be causing any hardship with whatever food scraps they must be eating.

A Busy Evening

This has been a busy evening in a number of ways. After her evening break, Mrs. Owl returned with a gecko (photo 1). She began to feed it to the owlets. Merely 2 minutes into this process, Mr. Owl arrived with a lizard. He expected his usual reception, which is for Mrs. Owl to reach up to the doorway and grab it from him. However, her mouth was full of gecko, so he came down into the box. A lot of confusion resulted, in which he tried to hand it to her, as the owlet heads bobbed up and down in anticipation of all this lovely food. (photo 2). As he could get nobody to take his offering (the owlets being too small to grab a whole lizard), he left after about a minute (photo 3).



The next chapter of this unusual evening involved a fair bit of worry on our part. After Mr. Owl left, we heard a Barred Owl call in the back yard. Barred Owls are much bigger owls that eat, among other things, Screech Owls. There have been a pair of Barred Owls in our neighborhood since last summer, and on occasional nights during the last few months, we have heard their "YOOOOU-aaaall" or the full "Who cooks for you, who cooks for YOOOOU-aaaall?" song. We have been concerned that they might prevent or interrupt the Screech Owl nesting by eating one or both of the parents.
So after hearing the Barred Owl call tonight, we didn't see Mr. Owl for nearly 2 hours. During this time, Mrs. Owl went out several times, sometimes for as long as 23 minutes, and returned with food each time. We began to get concerned that perhaps something had happened to Mr. Owl, and she was being forced to hunt for the owlets' dinner. We began to speculate on what we would do if he did disappear, when he finally showed up with a food delivery. It turns out we missed a couple of deliveries that were recorded on the camera frame captures on the computer. But he was absent for over an hour, and Mrs. Owl's hunting behavior was unusual. Our conclusion is that it was a rather warm night (still over 70 degrees at midnight), and that perhaps she didn't need to incubate the owlets all the time. Perhaps she decided she might as well join the hunting effort. That or a bit of cabin fever.

Just the Three of Us

It's definitely three owlets now.

In the second photo, Mrs. Owl feeds a baby.

In the third photo, you can clealy see 3 little fuzzy bodies.