22 May 2018
Final confirmation that this year's attempt at nesting has failed. I don't know what went wrong as the effort seemed to fizzle out rather than stop abruptly. The photo below was taken just now and the one below that three days ago so nothing has been into the box in that time. It is only the second failure in 10 years. Let's hope for more success next year.
05 May 2018
I fear something has happened to one of the birds as nest building seems to have stopped. I guess one may have been taken by a sparrowhawk. This was the view yesterday
and this is today.
Hardly a piece of grass has moved and if you compare with last week (below), no new material has been brought in. One bird was still visiting the box occasionally up until yesterday but I doubt very much that there will be eggs.
Only once in the last 10 years was the first egg laid later than this. If this ends up a failure it will be only the second time so overall it is not too bad.
29 April 2018
It is now 25 days since the nest building began and after another eight days there hasn't been much progress. The bird(s) pop in occasionally but nest building seems to have stopped. I don't know whether this is due to the cold weather or whether they have given up. I can tell at least one of them has been in as the image of the nest material is different each day. These are the last two days.
The latest date of the first egg was 10 May in 2013 so all is not lost. It could be that they are delaying because of the late spring. They need to time it so there will be plenty of caterpillars when the chicks need feeding and caterpillars need fresh tree leaves.
21 April 2018
Eight days after the last update there has been progress. The nest cup is not yet formed but space has been left for it in the centre at the back of the box. The blue tit has continued to take out nearly as much as she brings in so it is still quite an inefficient process. She seems to have a compulsion to grab a beakful of something just before she leaves and sometimes it is quite a lot of stuff.
Previous years' data from this box show that clutches started after 24 April never have more than six eggs so I don't think this will be a record year. From the look of the nest tonight I don't think this bird will be laying within the next week. I'll update again when she does, and perhaps before.
13 April 2018
Some progress has been made in the last three days despite the weather. The birds have been in and out all day, although the nest building is not very efficient. She is still almost as likely to take stuff out as bring it in. And she spends a lot of time hammering at the entrance or doing her little dance. This was this morning.
This is her bringing stuff in.
An this is after she had dragged a couple of loads out again.
Here she is doing the dance.
I think removing the material is just a programming error and isn't deliberate (as in serving a useful purpose). Despite multiple trips there has been only a slight net gain during the day. The weather is due to improve from tomorrow so with luck things will speed up.
10 April 2018
I think this bird was a bit embarrassed when she read yesterday's post (below) as she has been doing a bit of work this morning, even though it has been pouring with rain. It is still fairly inefficient as she sometimes takes stuff out with bringing anything in but overall there is a bit more than there was. The weather should improve after today so she may increase the work rate.
09 April 2018
Final confirmation that this year's attempt at nesting has failed. I don't know what went wrong as the effort seemed to fizzle out rather than stop abruptly. The photo below was taken just now and the one below that three days ago so nothing has been into the box in that time. It is only the second failure in 10 years. Let's hope for more success next year.
05 May 2018
I fear something has happened to one of the birds as nest building seems to have stopped. I guess one may have been taken by a sparrowhawk. This was the view yesterday
and this is today.
Hardly a piece of grass has moved and if you compare with last week (below), no new material has been brought in. One bird was still visiting the box occasionally up until yesterday but I doubt very much that there will be eggs.
Only once in the last 10 years was the first egg laid later than this. If this ends up a failure it will be only the second time so overall it is not too bad.
29 April 2018
It is now 25 days since the nest building began and after another eight days there hasn't been much progress. The bird(s) pop in occasionally but nest building seems to have stopped. I don't know whether this is due to the cold weather or whether they have given up. I can tell at least one of them has been in as the image of the nest material is different each day. These are the last two days.
The latest date of the first egg was 10 May in 2013 so all is not lost. It could be that they are delaying because of the late spring. They need to time it so there will be plenty of caterpillars when the chicks need feeding and caterpillars need fresh tree leaves.
21 April 2018
Eight days after the last update there has been progress. The nest cup is not yet formed but space has been left for it in the centre at the back of the box. The blue tit has continued to take out nearly as much as she brings in so it is still quite an inefficient process. She seems to have a compulsion to grab a beakful of something just before she leaves and sometimes it is quite a lot of stuff.
Previous years' data from this box show that clutches started after 24 April never have more than six eggs so I don't think this will be a record year. From the look of the nest tonight I don't think this bird will be laying within the next week. I'll update again when she does, and perhaps before.
13 April 2018
Some progress has been made in the last three days despite the weather. The birds have been in and out all day, although the nest building is not very efficient. She is still almost as likely to take stuff out as bring it in. And she spends a lot of time hammering at the entrance or doing her little dance. This was this morning.
This is her bringing stuff in.
An this is after she had dragged a couple of loads out again.
Here she is doing the dance.
I think removing the material is just a programming error and isn't deliberate (as in serving a useful purpose). Despite multiple trips there has been only a slight net gain during the day. The weather is due to improve from tomorrow so with luck things will speed up.
10 April 2018
I think this bird was a bit embarrassed when she read yesterday's post (below) as she has been doing a bit of work this morning, even though it has been pouring with rain. It is still fairly inefficient as she sometimes takes stuff out with bringing anything in but overall there is a bit more than there was. The weather should improve after today so she may increase the work rate.
09 April 2018
I am not sure what is going on here. I was away for three days and when I came back the birds hadn't added to the nest at all. Then this morning one of the birds (I think it may have been the male) was coming and taking stuff out. Both birds were coming to the box frequently but nothing was getting done. 
This is the picture just now so a small amount has been added this afternoon. But there is a lot more to be done if they are going to make a go of this. They may be young birds and haven't quite sorted out what is to be done.
04 April 2018
The blue tits have been coming into the camera box for the last eight weeks but work on building the nest started only this afternoon. They have been checking out the box regularly, although I obviously can't be sure it has always been the same pair. Most of the time I have seen the female but sometimes the male comes in first and calls to his mate. When she comes in he leaves so quickly that it has been very difficult to catch them both on a still frame.
Here they both are on video. The female has been spending a minute or more each time checking out the box.
I am surprised she chose today to start building as it has been so wet and I thought she would wait for a dry day. This is the equal latest start day for nest building in the camera box. This photo shows the first few strands of nest material.
Once there is more material the female will start to fashion the cup of the nest at the back of the box by doing a circular dance while fluttering her outstretched wings. It was interesting to see her doing that today, even though there is hardly anything in the nest so far.
The box went up in 2009 and had blue tits in every year from 2010-2016. In the first year it had great tits and last year I put on a 32mm entrance plate and the box had tree sparrows. Although they were great to see, videoing the sparrows was very difficult because of the construction of their nest so I reduced the entrance plate to 25mm this year and I now have blue tits again.
I have records of the date of the start of nest building for 4 of the previous 5 blue tit nests and it varied between 09 March and 04 April, presumably influenced mainly by the weather. This has been a miserably cold wet spring and this is presumably why they have waited so long this year. First laying dates have varied from 23 April to 10 May with clutches of 2 to 11 eggs. The later the first egg the smaller the clutch so I expect this won't be a record year. In the 7 years of blue tit nests altogether there were 43 eggs, of which 42 hatched and all 42 fledged, so productivity has been high.
Data from the BTO Nest Record Scheme show that blue tis have been laying their eggs earlier over the past 50 years but there is very wide year to year variation (depending on the weather). My local laying dates have been about three days later than the national average. (01 April is day 91 so these are around 20 April - early May.)
More BTO data show that clutch sizes have been getting smaller,
and the number of fledglings per breeding attempt has fallen slightly,
but overall the blue tit population is doing OK.
As in previous years I will document day-to-day progress on this "Nestbox camera 2018" page, with occasional updates on the home page. I just hope these two blue tits will evade the sparrowhawk.
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