I had almost given up on a nest in the camera box this year. Then three days ago I saw a single strand of grass that hadn't been there the day before. And two days ago a blue tit arrived.
As well as having a good look around it did the wing-spread dance that is used to place nest material and form the nest cup - even though there was only one strand of grass to work with! I hope this is good news and is a sign that blue tits will move in. I have seen them jumping around in the bushes opposite so they are certainly interested. Here is a short video of the bird's visit.
My nest box was put up in 2009 and was occupied every year from 2009-2019, once by great tits, once by tree sparrows and nine times by blue tits. In the nine years blue tits produced 54 eggs (0-11 per year) of which 53 hatched and all 53 fledged. For the last two years the box has been unused with no attempt at nest building. I am not sure why as there have been plenty of blue tit nests in other boxes.
This is a late start but the weather has been miserable. Previously the latest start for building was 04 April. The date of the first egg has ranged from 23 April to 10 May with a later date strongly associated with a smaller clutch, probably weather-related.
Data from the BTO BirdTrends show that nationally blue tits are laying their first egg about a week earlier than 50-odd years ago, probably related to climate change. There is wide year-to-year variation, again probably weather-related. (Day 110 is 9th April.). The first egg has been laid here between day 120 and day 137, so later than the nation average as we are farther north.
Over the same period the BTO data show a reduction in clutch size, brood size and number of fledglings.
Despite this blue tits are doing well with an increase in adult survival.
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