I have installed this separate page to allow me to give regular updates on progress in the nest box without filling up the main blog with too many posts. A weekly update will appear on the home page, mainly on Sundays or Mondays.
11 June 2016 - day 20
Stop Press. The chicks caught me out by fledging this afternoon. See today's post on the blog home page for details.
11 June 2016 - day 20
Several times this morning I thought the birds were about to depart but in the end they decided not to. I suppose it may have been the weather that put them off. In the previous six years they have always fledged on the 18th or 19th day after hatching. I'm not even sure who makes the decision - whether it is the parent birds or the chicks.
Everything is a bit subdued inside the box just now but earlier there was a lot of activity and the chicks had moved right up to the front of the box.
As yesterday, several times a chick jumped up to look out of the entrance but didn't fancy leaving.
Sadly I'll be away tomorrow morning so I'll not be able to see them go.
10 June 2016 - day 19
I got up early this morning thinking that the birds might fly but they didn't. At one stage they looked set to go. Three times a chick flew up to look out of the hole
and early on the parents were tempting them with caterpillars outside.
First thing this morning the chicks were at the back of the box
but they soon moved towards the front.
There has been lots of flying practice this morning.
I'm pretty sure they'll be off in the morning. If they are I'll put a report on the home page of this blog.
09 June 2016 - day 18
Photos of the parents from this afternoon as they may be off tomorrow. Both looking careworn. This is the male.
And this is the female.
Lots more wing muscle exercises but they are difficult to catch on video. The chicks will be off soon, maybe as early as tomorrow.
07 June - day 16
There is a lot of stretching and preening going on with occasional wing warm-up exercises. The chicks are quite noisy now and are easily heard outside the box. They are staying in the warmth and security of the nest cup for now.
04 June 2016 - day 13
Last night was the first time the mother didn't sleep in with the chicks. This happened last year on day 12, a week before fledging so, with luck, the chicks will depart a week from now. Here they are snuggled up to keep warm.
Mother was in at first light this morning to bring them an early breakfast.
03 June 2016 - day 12
This clip shows several things. Firstly I think the chicks' eyes are now open. And they are very aware of their growing wing feathers and are spending more time preening. Then the mother comes in with some food and thinks about doing more housework but is interrupted by the arrival of the father. He is as indecisive as ever and can't decide which chick to feed. The noise is from a mower on the golf course.
01 June 2016 - day 10
The mother spends a lot of time doing the housework when the kids think she should be out collecting food.
At least dad has the right idea.
31 May 2016 - day 9
The miserable cold grey weather continues but there was a brief sunny episode yesterday afternoon. I took the opportunity of photographing the adults outside the box for the first time. This is the male. He has a high white forehead and dark markings or missing feathers on his face.
Not a great photo but this is the female. She generally approaches the box by a slightly different route so this is the only time I saw her.
Both parents look a bit careworn and will be pleased to moult into new feathers once the chicks are independent.
30 May 2016 - day 8
The chicks are noticeably more active this morning, with lots of stretching, wriggling and yawning going on. Their eyes are still closed but their wing feathers are developing and they are starting to preen.
The parents are working hard to keep the chicks fed, as you can see from this clip. The mother spends less time brooding them now as their feathers develop and the demand for food increases.
28 May 2016 - day 6
It is quite easy to tell the male and female apart as they visit the box. The female looks like this from behind.
And this is the male. I'll take some photos of them outside the box in the coming week.
27 May 2016 - day 5
The weather remains cold and gloomy but the birds are having no difficulty finding food for the chicks. The size of the caterpillars is increasing and they now easily swallow St Mark's flies.
26 May 2016 - day 4
The chicks are noticeably greyer and stronger than yesterday and have started cheeping.
25 May 2016 - day 3
The chicks have already changed appearance in less than 48 hours. They are beginning to sprout grey feathers on their heads but still look mostly like miniature oven-ready chickens. Their eyes are not yet open and they lie in a heap except when begging for food.
24 May 2016 - day 2
All six eggs have hatched by this morning. Now the hard work begins. I reckon the parents will be flat out until fledging on 10th or 11th June.
23 May 2016 - day 1
Five of the six eggs have hatched in 24 hours and there is still time for the sixth. The parents are bringing in small caterpillars but even they look too big for the chicks. The chicks can barely raise their heads.
22 May 2016
The first egg has hatched this evening. The mother was obviously excited and when she left the box briefly this was my first view of the tiny chick.
The parents immediately wanted to feed the chick and brought in tiny pieces of caterpillar. The clucking noise is to encourage the chick to open its beak. First the mother tried, then the father but he soon handed over to the mother.
I expect the other eggs to hatch within 24 hours.
20 May 2016
The female has been sitting on her six eggs for 11 days so I expect them to hatch some time next week. The male regularly brings her food such as this caterpillar.
13 May 2106
The female is sitting on her six eggs most of the time. The male brings her food from time to time - mainly caterpillars or St Mark's flies.
11 May 2016
I have been away for a couple of days and when I checked this morning there are six eggs. I expect that is the completed clutch, with the last one having been laid the day before yesterday. The bird is sitting on them most of the time.
There does seem to be a correlation between the date of the first egg and the clutch size. Looking back at the data from this box for the last six years there have been 11, 11 and 8 eggs when the first was laid before 25th April and 2, 4 and now 6 when the first was laid after 28th April. The time from first egg to hatching ranges from 18-25 days and from last egg to hatching 10-19 days, both of which seem to me to be surprisingly wide ranges.
The BTO quote an incubation range of 13-15 days but don't say whether it is from the date of the first or the last egg. They quote a fledging time of 18-21 days. In the birds in this box it is always 18 or 19 days.
I expect we're looking at hatching in the third week of May and fledging in the second week of June.
08 May 2016
I couldn't see the eggs yesterday as the bird had left them covered but I assumed there were three. Today there are four, with more to come as the bird is not brooding them yet. Laying could go on for another week. It is amazing that the eggs can be laid 10 or more days apart and yet all hatch within 24 hours.
06 May 2016
The second egg was laid overnight or early this morning. The eggs are not very easy to see as the bird tends to cover them when she goes out. She doesn't brood the eggs at this stage but will do so when the last or last but one is laid. I expect one egg a day now until the clutch is complete.
05 May 2016 - First egg
04 May 2016
Courtship feeding going on in the box this morning. The male is at the bottom of the picture.
03 May 2016
Tonight the bird has been very excited, jumping in and out of the box with a piece of leaf, seemingly not quite sure what to do with herself. No egg so far but perhaps tomorrow?
02 May 2016
Last night was the first time the female has slept in the box.
As you can see she is a restless sleeper.
01 May 2016
May Day, and it is cold and raining again. This is the 28th day of nest building and the job is more or less complete. The nest itself is now lined (top right in the photo). I haven't been watching much so I don't know if the male has come in to check recently. I expect the first egg will be laid in the next few days.
26 April 2016
Slow progress. I think the continuing cold weather is not encouraging the bird to finish the nest. Today we have had snow and sleet for much of the morning so she has spent some time in the box just sheltering from the weather. It must be warm and dry in there but it is interesting that she doesn't roost in the box at night.
The main part of the box is now filled but the corner where the nest itself will be is still unfinished.
Only once in the previous five years was the first egg laid after the end of April so we look to be on course for a late start to laying. The weather forecast for the next week shows the peak daytime temperature not exceeding 11°C here so the trees are behind schedule and the caterpillar crop that will feed the chicks in a few weeks time will also be delayed.
22 April 2016
This is the 19th day of nest building and the floor of the nest cup (in the top right as we look at it) is just starting to be covered this morning. Only once in the previous six years was the first egg laid after the end of April but this has been a cold spring and the cold weather is set to continue for the next few days. I doubt if the bird will start laying until May.
18 April 2016
It is two weeks since nest building began. Progress has been better in the second week so maybe she is getting the hange of it. More moss and grass was brought in over the weekend. The cup of the nest itself is yet to be built.
Here is the female this morning with a very small contribution.
The weather continues cold and is forecast to be colder next week so I expect the birds are in no rush. Laying probably won't begin for another two weeks or so.
15 April 2016
This is as far as we have got. The front half of the box is filled in but a lot more material will be needed to form the nest. There is no rush as laying isn't likely to begin for another two weeks.
Here is a short video clip showing the female doing her fluttering dance to spread out the nest material. She'll do the same to form the cup of the nest.
13 April 2016
I have been away for a few days and on my return there has been some progress in the nestbox. The weather has been very poor so it may be that the bird doesn't want to bring damp material into the nest. As one would expect, the body of the nest will be at the back of the box, on the right as we look at it.
09 April 2016
So this is as far as the bird has got after six days. She doesn't seem to have the hang of it at all. She spends as much time taking stuff out of the box as bringing it in so the net effect is not much. At one point I wondered if she was raiding this box for another one but I don't think so. Judging by previous years things should improve but it is frustratingly inefficient to watch.
08 April 2016 - Shelter from the storm
Mrs B-T definitely has a permanent dark zig-zag mark on her left cheek, reminiscent of Harry Potter's lightning scar on his forehead. This, and the narrow white band above her beak make her very easily distinguished from her mate. I'll take some proper photos of the two of them outside the box but only when the nest is built so that I don't put the birds off.
Yesterday we had a hailstorm. I came in from the garden to shelter and Mrs B-T did the same, hiding in the box until the storm had passed.
06 April 2016
Nest building always gets off to a slow start, especially when the weather is poor as it is this week. The female is bringing in a few bits of moss, mainly in the mornings. Her behaviour is very ritualised and sometimes she picks up a bit of moss and takes it out again! Not working to maximum efficiency. It was frustrating watching last year's bird do this as I thought she'd never get it finished. Although there isn't much material this female is already doing her fluttering spread-wing circular dance which will eventually distribute the stuff and form the cup of the nest.
Yesterday and today the male popped in very briefly to check on progress.
He came in first and called to her but then left a second or two after she came in.
If you compare the close up of the male above with the female below you can see she has a mark or dark feathers on the left cheek which, for the moment at least, makes it easy to tell them apart. He also seems to have a whiter forehead, noticeable in the photo of the two of them above.
04 April 2016
Nest building started this morning in my camera-monitored box just outside the front door. After six years of blue tits this year I changed the entrance plate from 28 to 32mm, hoping for either tree sparrows or great tits. So who has moved in? Another pair of blue tits! I haven't kept details of the start of nest building for each year but looking back through the video clips and stills I can see it was 27 March in 2010, 29th in 2012, 9th March in 2014 and 29th last year. So this is a late start, presumably because of the recent cold weather. Tree sparrows are already active in some of the other boxes and I have also seen blue tits and great tits in other boxes. As I did last year, I'll make another page (accessible via the Nestbox Camera 2016 tab above) to document day-to-day developments once there is more activity and put a weekly update on the main page.
Although nest building started almost a week earlier last year, the first egg wasn't laid until 29th April. The first egg hatched on 18th May and the chicks fledged on 5th June. So if the weather improves there is plenty of time for this year's birds to catch up.
Each year I have submitted data from this box to the BTO Nest Box Challenge. Being in the north of the country I expect laying and fledging dates here to be slightly later than average. BTO data below for blue tits show the laying date (first egg) for the previous six years. My dates were 22/04/2011, 24/04/2012, 10/05/2013, 23/04/2014, and 29/04/2015 - on average three days later than the national average.
The female bird builds the nest alone, although several times last year the male bird popped in to have a look as well - perhaps he's in charge of quality control. He does bring in food for the female when she is incubating the eggs and both parents feed the chicks. I'm looking forward to seeing how this year's occupants get on.
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