There has been a lot happening since the last blog post when I thought that possibly we were only going to have two eggs. Aluco lay these two and then, when the period passed for a third, I thought that perhaps we were stopping at just the two. When Aluco left one night, it was clear that there were some dimples in one of these two eggs. It was difficult to see it these are going to affect the development. I fear that this egg is not viable. So, when 3 days later, another egg appeared, I was very surprised. Aluco had already started incubating, so this third egg will hatch several days after the first, which puts it at a distinct disadvantage unless there is a lot of food being brought in.
Normally, we don't get many views of the male, Strix. He will bring food to Aluco whilst she incubates as she will not hunt for herself, but it is usually just s short glimpse of him arriving at the nest box. We have another nest box at the very end of the garden. It faces out over the River Severn and gets the sun just about all day. It has a wide veranda and both owls use this box out of breeding season. In breeding season, Strix sometimes uses it as a place to roost. On the 5th, he spent all day there, either sunning himself outside or inside the box.
It is a real treat to see him up close and in daylight. He is a little smaller than Aluco and has a very pale facial disc, compared to Aluco's browner face. He is so beautiful! I have watched these clips over and over again and I never tire at looking at him.
On Feb 6th, Aluco left the nest box for a short period. She only leaves the box for about half an hour every 24 hour period. As she came out the nest box, it was clear that she was limping quite badly.
These are wild animals and injuries do happen. With her spending most of the next month incubating, I hoped that it would give it a chance to recover. I was very relieved when, after just a few days, she seemed to be using the leg normally again.
On the 7th Feb, Aluco left the nest box to reveal her third egg. Tawny owls usually have 2-3 eggs in a clutch.
Every year, I worry about how much food is being brought into the box for Aluco. On average, he only delivers one, maybe two, prey items. These are usually wood mice, rats or birds. If she has not eaten for nearly 24 hrs, she is very hungry and it doesn't last long!
If you are watching the live stream, you will see that Aluco changes position quite regularly. It must get uncomfortable sitting in there all day, so she stretches and turns around. She will also check on the eggs and move them, turning them. This ensures that the owlet develops properly. She has a brood patch, which is where she removes the feathers underneath. This ensures skin contact on the eggs. You will see her stretch up to position herself and then she will drop down on them and wiggle to make that contact.
Before I started filming tawny owls, I had not appreciated how many birds they catch. It is often early in the morning that Strix will appear with birds. It is often difficult to tell what species they are, but I have filmed everything from jackdaws and magpies to goldcrests and blue tits being brought in over the last four years.
Incubation is 30 days, so for now, enjoy the lovely views of Aluco incubating. When I was on site last week, I zoomed the camera in a little ... what a beauty!
We have a camera on a small woodland waterhole, close to the nest box. A lot of rats clean up the seed at night. It was good to see Strix take advantage of this. He was unsuccessful this time, but there is a lot of opportunities for a meal in this location!
Let's hope there are no more dramas now and the rest of the incubation period runs smoothly.
