Mike Coon wrote:
It might be because the day-length is similar to that in Spring and
they have not noticed that days are shortening instead of
lengthening. I don't think you'll see any interest until the weather
is bad enough to justify their roosting in the box.

An update. The pair is still very interested in the nest box. I did see a
third bird taking an interest but it was definitely not welcomed!

When I saw a bird removing a fecal pellet, which has been reported
elsewhere as an activity of the female tidying up after a roosting male, I
thought I should have a night-time peek. This confirmed that a bird is
roosting, surrounded by poo that I did not leave when I cleaned the box out!

But I don't know whether the roosting is a reaction to the recent frosts or
a (premature) reservation manoeuvre in anticipation of nesting.

Perhaps it will stop when the clocks go back! ;-)

Mike.
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