Two Eggs

Mrs. Owl was out all of last night, from 8:06 pm Monday night until 5:45 am Tuesday morning. The first photo shows her returning. She spent all day incubating and turning the egg. Occasionally she preened her feathers. Sometime between 7:23 am and 4:36 pm she laid another egg. She never got off the first egg long enough for us to see exactly when in that stretch the second egg was laid.

Tonight, she left around sunset, and hasn't been back in 4 hours so far.

Monday night was a cold night for spring, dipping into the upper forties, so she probably hasn't started incubating the eggs in earnest. Once she starts incubating them, she will only take short 5-20 minute morning and evening breaks, relying entirely on her partner for hunting.

In our experience, full-time incubation usually starts with the second egg, so tonight may be the last night she spends any significant time outside the box.


Unlike some birds, owls start incubating before the full clutch is complete, which leads to staggered hatching, 1-2 days apart. This means the eldest owlet will be significantly bigger than the youngest at first. This, combined with the owls' tendency to feed the most aggressive, means that if the food supply ends up being disappointingly small, the youngest will probably starve. Luckily, this year, the abundant rains probably will mean an abundant supply of insects and reptiles, and all hatched will probably make it.

This strategy allows owls to maximize brood size without knowing in advance how good the food supply is going to be. The youngest ones are a reproductive bonus, if the food supply ends up being average to good. But in a bad year, while some may die, it ensures that at least some get enough food to survive and fledge. The alternative could be starvation for everyone in a famine. A seemingly harsh strategy, but in nature, whatever strategy produces the largest number over time will tend to flood out the rest of the strategies, just by sheer exponential math. This is the basic mechanism of evolution: It's not really survival of the fittest. It's flooding of the gene pool by the reproductive strategies that produce the most surviving offspring, generation after generation. They do have to be fit enough to survive to reproduce and pass on an above average batch of youngsters, hence the notion of fitness. But it's really a game of numbers, not strength.

It's not all quite so cold and calculating as the previous description suggests. We have observed owls ignoring taller offspring and pushing down to feed smaller ones. But we haven't really experienced a year of famine, and our friend Chris Johnson has experienced young owls dying and becoming food for their siblings.

An egg and a bird

Sometime this afternoon, Mrs.Owl laid an egg. We think there was a photo from about 2:10pm in which there was no egg, and then at about 4:02pm, you can clearly see an egg.
Also visible in this photo is a bird in Mrs. Owl's mouth. We haven't had time to review last night's photos to see when it was brought in, or what species it may be.

Wet Morning

Mrs. Owl just returned to the box about 7:34am after enduring a huge thunderstorm outside the box. We have no idea why she didn't just return to the box before the storm started. Those are raindrops on the glass that she brought in on her body.

Interesting Photos from Today

In the first, you can see her "ear" tufts in reaction to my stepping out into the yard. She had been in the doorway, and I didn't realize it. She dropped down. However, she was back in the door watching the morning a few minutes later.

In the second picture, she is stretching up just before she climbs onto the upper perch, using her wings as leverage.

In the third picture, she watches from a recessed position. I think she really likes this upper perch.

Here for the Day

Mrs. Owl showed up at 11:32 on March 16th, after 2 full days absence. She spent about 25 minutes in the box, rearranging the nest floor. She returned at 12:56am for 12 more minutes, and then stayed out all night until 7:24 am on the 17th. She is still out hunting at night, and will do so until she (hopefully) lays and starts sitting on eggs.
She stayed all day, sitting up in the entryway a few times during the day. She left at 7:53pm, returning an hour later at 8:51, but only for 6 minutes. Right now she is out of the box, hopefully on a St. Patty's Day date with Mr. Owl. We hope to find her in the box in the morning, and maybe with an egg.

Nobody home

Nobody visited the box last night. We'll probably have to wait and see what happens tonight.

Here To Stay?

Sunday morning we woke to find Mrs. Owl in the box, probably to stay put for the day! She paid us a brief visit Saturday night at about 8:50pm, but only stayed a few minutes. Sunday morning, she showed up at 7:10 am for a few minutes, and then again at 7:36 and stayed all day. She spent quite a while firmly planted on the top perch (thanks Max for that idea!).

We've had a few brief visits by wasps, too. Hopefully they won't decide to try to set up shop in there.

She stayed all day, even showing herself in the opening a couple of times. At 7:55pm she left, returning 20 minutes later, a fairly typical time for an evening "constitutional" (bathing, pooping, spitting out a pellet, etc.) But instead of staying the night, she only stayed for 5 minutes, and we haven't seen her since (it's now 9:06pm Monday night).

Hopefully she'll return tonight and spend another day in the box.

Morning Visit

At 5:43 this morning, an owl visited for 6 minutes. This was likely Mrs. Owl, as she moved around the nesting material on the bottom of the box during the visit. We think we've only seen this behavior from Mrs. Owl. So, hopefully, she is preparing the accommodations for a lengthy stay.

The camera was out of commission yesterday evening, so we don't know whether anyone visited last night.

Squirrel Visit

Brief squirrel visit at 7:15 this morning.

First Visit

Last night, an owl visited! Based on past experience, it was likely the female, as she seemed interested in the interior of the box, but we can't be sure. The owl arrived at about 7:21pm, staying for about a minute, and then came back at 7:27, staying for 10 minutes. Hopefully, the female will come to stay in a few days and start laying eggs. In our box, the egg-laying has usually happened pretty quickly. They don't spend much time setting up house.

And they're gone

The last owlet had a mostly quiet day in the box. He did seem to take advantage of having all the room with no brothers in the way. He walked around the box, stared at the camera compartment and at things in the box (ants?) He stretched his wings (look at the beautiful flight feathers in photo 3). The flight feathers had grown in just 30 days since hatching. In the evening, rather late (about 8:40pm), he went into the doorway and looked around. But then he popped down again and we thought it was getting a bit dark for him to venture out.
However, around 9:00, he got active again, stretching wings and climbing around. Then he got up in the entrance and sat a couple of minutes, but with his feet safely planted on the inside rim of the hole. Then he did what his two siblings did before, and shifted the feet and his weight to the front rim of the entrance. And then he was gone.
It was too dark to see where he went, but I heard the sound of him crashing into leaves, so I think he landed in a tree. I went to look with a flashlight, to be sure he was safely off the ground from cats, and didn't find him. We can only hope for the best at this stage, but we have yet to end up with an owlet on the ground. One owlet one year ended up on a the compost pile fencing, but the rest have all landed in trees.
We may or may not be able to locate them in the branches the next couple of days, but after that, this will likely be the last time we'll see them. They should spend the summer in our neighborhood, learning to fly and hunt. Then, they'll be chased off the territory to avoid inbreeding, and will find homes of their own. We feel very fortunate that they chose to nest with us again. We've learned some lessons about bee management, and will likely be able to allow bees and owls to be peacefully separated should this happen again.
We thank all those people who watched the screechcam this year, and told us their own nestbox, owl, and bird stories, or just told us how much they were enjoying it. Hopefully we've entertained and educated a few people with this story. Join us again next year. We'll try to send out an update on twitter and the yahoo group when the season begins again.

And then there was one

This morning, the second owlet fledged. It was quite a busy night with lots of moving around, some mutual preening of feathers, and some jostling for the entrance hole. They did some wing stretches (photo 1). The parents continued to bring food (photo 2). Then, close to 6:10am, one of the owlets (we assume the middle child, but can't know), got up in the entrance. He sat there for a couple of minutes, then moved his feet further out, so they were sitting on the outside ledge. After a couple more minutes, he flew. His nestmate looked up suddently at his departure, and within 7 seconds was up in the window himself. But he must not have felt ready to follow suit, and came back down. He was fed soon afterwards (photo 3: a cicada). You can see him gulping it back in photo 4. Why leave when food keeps coming in? We're expecting a departure tonight, but will wait and see. The sycamore and cedar elm trees that they perched in last year in the days following fledging are much sparser in leaf due to the drought. I looked for, and failed to find the fledged two this evening, so perhaps they are staying down in the denser-leaved ligustrum or live oak branches.
Now we wait to see what the remaining nestling will do tonight.

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.