The 2008 Nestbox Diary
May - Part 3
The chicks head for fledging
13 May - 14/15 days since hatching, and about 5/6 days to fledging.
At 11am it's so far so good for the Starlings today, with all three survivors apparently moving about well, all anxious to be fed - some of that feeding taking place at the entrance.
At the end of the day the three chicks were still active, and I have seen a number of wing flapping sessions taking place.
The wing testing also occurred occasionally in the Great Tit box, but I'll come back to that later.
The Great Tit chicks continue to make their good progress, with both parents making regular food deliveries.
I failed to photograph what the male (right) had brought in, but it was very thin and long, and didn't look like a caterpillar.
As usual, the caterpillars that have been brought in have ranged from the (almost) oversized,
to the very small!
I guess that over the day each chick is getting its share of large and small. I can't see one that is being left behind in the race to fledge.
Yesterday, I mentioned that the female was bringing in food pellets. Well, they have been on the menu again today, and this time I was ready to record one such delivery.
Looking at this picture of the chicks in restive mood, I can no longer see feather sheaths protruding,
And the ear of this chick is now completely covered - but its downy tufts are still obvious.
And for the final 'chick pic' of the day, a different view of a wing that was being stretched.
Usually, I'm intent on photographing the flight feathers, but this time I caught a glimpse of the underside of the wing instead.
The enlarged image on the left shows how it is being covered with downy feathers, which are still partially enclosed in sheaths.
Yesterday I mentioned hearing the chicks for the first time. Today they were even more vocal, and this evening I recorded a feeding session. This recording starts with the low frequency sounds (last less than a second) of one of the chicks exercising its wings just before a parent enters with food. The recording continues after the adult leaves, and the volume of the chirps gradually decreases until the chicks fall silent again.
Click here to listen to the recording (537KB - 34 seconds)
When the chicks exercise their wings they often flap them so fast that they just appear as a blur (except when 'frozen' in a photograph by the use of flash - see yesterday's entry).
Having recorded the sound of one of these sessions, I decided to take a look at the recording using the software 'Audacity'.
On this trace of the beginning of the recording I have indicated with red lines the portion of the line that represents the wing flapping. It suggests to me that in around 3/4 second the chick flapped 14 or 15 times, which would make the 'flap rate' nearly 20 per second.
A final note - both the Starlings and the Great Tits have been beaten to fledging by at least one Goldfinch youngster that I saw begging for food early this evening!
14 May - 15/16 days since hatching, and about 4/5 days to fledging.
Over the last three days the temperatures have been slipping back down, from highs of 24C on the 11th, 22C yesterday, and 20C today. The dry weather has continued but is forecast to end tonight.
The Starling chicks were left on their own last night and it looks as though they will be tonight as well. And at approaching 9pm Great Tit chicks are also on their own.
For the Starling chicks, the first feed came at around 5.17am. At approaching 6.30am their mother decided to remove one of the dead chicks.
For the next couple of hours the other dead chick was still visible in the nest cup, although it may be quite difficult to see in this image.
I'm afraid that the quality of images that I'm able to get from the Starling camera is declining quickly, probably down to the activity of mites on the lens surface. Hopefully they will wait another week before they blot out the view completely.
At just before 9am The second body was finally removed.
It wasn't until a bit later in the morning that we realised that this had happened after Sheila found this corps in the driveway - there was no sign of the second one.
I wonder why the mother waited so long before removing them from the nest.
I only took a few pictures of the Great Tits today.
Supplies of caterpillars continue to be good, with another large green one being brought in here.
We've reached the point where the chicks are getting to look much more like their parents while tucked into the nest cup, if you ignore details like the beak, and the short tail.
Here, mum pauses during one of her sessions of rooting about the bottom of the nest cup.
I've seen numerous sessions of wing muscle exercise going on today, and this one was carried out in the perfect spot of a photograph.
As I said at the beginning of this entry, the Great Tit chicks are on their own tonight, something I expect to see happening at this stage in the nesting process.
15 May - 16/17 days since hatching, and about 3/4 days to fledging.
Well, the hot weather is not history. Today we have had wall to wall low cloud, a high temperature that didn't even manage to reach 14C, and this evening it is raining.
The low temperatures were reflected in the less energetic behaviour of the chicks, especially the Great Tits who spent just about all day huddled together in the nest cup.
This morning, the Starling chicks were looking towards the entrance by 5.25am, but the first feed (at the entrance) didn't arrive until ten minutes later.
When the female did come into the box a little while later she spent a short time sitting on her offspring!
Yesterday I made a mistake when I said that the second dead chick had been removed. In fact it was left just below the entrance - you may just make it out in the picture.
Later in the day I thought that we were losing another chick.
At lust after 4pm one of the adults brought in what looked like a beakful of bread (or similar) which was readily accepted by a chick.
However, for the next six minutes or so the chick was in obvious distress, shaking its head vigorously and appearing to be choking (pic 1). Then it stopped moving about and slipped down onto the nest (pic 2).
It extended its wing, and kept it outstretched for the six minutes, showing no reaction on the two occasions when a parent entered (pic 3). Then it slowly slipped down into the nest cup (pic 4). It folded its wing but then stayed on the bottom of the cup, with its tail showing for over eight minutes (pic5) before suddenly reviving (pic 6).
Tonight the three Starling chicks are alone once more.
The Great Tit chicks received their first visit by mum at 5.30am and as I mentioned at the beginning, they spent most of their time huddled together to keep warm.
There seemed to be only two reasons for leaving the group, to exercise their wings, and to receive food.
This chick is stretching a wing during a preening session, and prior to flapping its wings.
In this picture of a chick's wings there are now no feather sheaths visible.
In this second image the wings are almost fully extended - no wonder that the other chicks are keeping their heads low.
The Alula (thumb feathers) of the right wing is clearly seen.
Caterpillars continue to be the main part of the chicks' diet.
Most of them seem to be green in colour, but they appear to be of a number of different species.
I thought I'd take a closer look at a few that were brought in while I was at the nest box.
This next one is thinner, and darker in colour,
and the last one has a sharply pointed red spike at its rear end.
This should make it possible to narrow down the species. My caterpillar guide shows a similar caterpillar that lives on Oaks - could it be Svensson's Copper Underwing (Amphipyra berbera)?
Tonight, the last food delivery took place at 8.07pm before the chicks were left on their own for the night.
16 May - 17/18 days since hatching, and about 2/3 days to fledging.
Another grey morning, a temperature of 11C at 8.45am, and all chicks huddled together for warm in both boxes, although the Starlings are taking an occasional trip to the entrance to look out for the next food delivery.
Today there has been an increasing sense that the chicks are readying themselves for fledging, with lots of wing testing by both Great Tit and Starling chicks, and in the case of the Great Tits, at least a couple of very brief test flights!
But first, the continued business of food supplies. For the Great Tits, the green caterpillars remain the main food type.
With only one food item brought in on each visit, there is always competition, and when this large caterpillar was offered, the ends were grabbed by two chicks, although only one would end up with its hunger satisfied, for a while at least.
While I was watching the box early this evening, the mother brought in a couple of more 'exotic' caterpillars (when compared with the usual green ones!).
Unfortunately, each time my reactions weren't quick enough to focus on the caterpillar before it disappeared into a mouth.
The two, similar caterpillars were brought in over a short period of time, so perhaps the female found them on the same plant.
The temperature hasn't got much above 12C all day, but while the chicks spent time huddled together, there was much more activity today as the chicks preened, stretched and flapped their wings.
There was a surprise in store for its mother when a chick decided to stretch its wings while she was in the box.
The chick seemed to drop back into the nest cup,
but then the stretching then turned into vigorous flapping and the chick took off, landing on its mother's back before she had chance to react!
As I write this at 9pm I'm being distracted by the sight of one of the chicks that is still trying out its wings while its siblings are trying to sleep, and it just took off momentarily.
For the Starling chicks, the day stared with a first look out at 5.20am followed by competition between all three chicks for the best position at the entrance when the first food was brought at 5.30am. Around 9.30am the mother tried again to remove the dead chick but failed again, leaving it up against the entrance.
During the day, there was some wing testing in their box, although I didn't see any sign of a chick taking off!
There was no repeat of yesterday's choking scare, and this evening all three Starling chicks appeared to be healthy, despite the continued presence of the body of their dead sibling next to the entrance.
The adults are taking more interest in the left hand box now - I wonder if they are already preparing for a second brood, as happened last year.
17 May - 18/19 days since hatching, and about 1/2 days to fledging.
The grey, cool weather continues with a maximum temperature of 13C. Despite there being a glimpse of blue skies this morning, the low cloud soon rolled in and while there was no rain during the day, there was a touch of dampness in the air this afternoon.
The cool conditions encouraged the chicks in both boxes to stay together for warm, but the need to preen and exercise ready for fledging meant that the chicks were very active today.
Here are the Great Tit chicks during one of their restful moments. Look carefully and you will see all six chicks, although one has its back towards the camera.
The tranquillity doesn't last long, as one decides that a wing needs some attention.
Then, the others need to duck as a full scale test is carried out on those wings.
This second picture of the same event shows how the chicks have now outgrown the nest box, at least when their wings are extended.
The inside of the box is about 6" (15cm) wide.
The caterpillars keep coming,
and so do the pellets. This is another picture to include all six chicks.
The pellet could well have come form our bird table as I decided to try some 'Seed & Insect suet Treats' from my local garden centre
With fledging due either tomorrow or the day after, the chicks continue to preen and stretch their wings as I write this at 8.20pm - in fact, I've just seen one of them launch itself into the air and fly up to a top front corner of the box. It was after 9pm before they started to really settle down for the night (without mum present).
The Starling parents continued to make frequent food deliveries today, and their chicks were very active in the box, although I'm not sure that they are exercising their wings as much as I see the Great Tits do.
On rather sad aspect of today was that anyone looking up at the box from our driveway would have seen the head of the dead chick protruding out through the entrance, and it stayed like this for most of the day. It remained there despite the adults trying to remove the chick from the box several times.
You can see the body of the chick in this picture of the three healthy youngsters.
To end today's entry, a different nesting predicament facing neighbours from opposite us. We knew that they have House Sparrows nesting in their roof, but today they came across the road to tell me that one of the parents had been seen feeding a chick through the holes of an air brick. The problem was that the air brick is just a foot or so above ground level. I went across, and sure enough you could hear the chirping of a hungry chick that was very close by, but inside the cavity wall of the house.
The Sparrows have been going in and out of the roof space for at least a couple of weeks, so I could only assume that a chick that was nearly ready to fledge had wandered from the nest and fallen down between the two layers of brickwork. There would be no chance that the sparrow could get back up to the top of the wall. With the options rather limited, on my suggestion a hole (as big as a Sparrow box entrance) has been drilled through the outer skin of the wall, next to the air brick, in the hope that the youngster will find its way out. The hole will be left open for perhaps the next week before it is sealed again.
Click on the images to see larger versions -