Box1 has a visitor!
This looks an old hand. It's breast feathers, which you can see a bit of at its side, look ruffled and its plumage generally has that well-used look.
At last, something seems to be going on in Box1!
It doesn't seem to do very much before leaving. Again, you can see its generally scruffy look.
It's back again. But is it the same bird? This one looks much smarter.
Clearly something outside is antagonising it!
Just another bluetit. Clearly, not a friend!
It takes a closer look.
It's a very smart bird, isn't it?
The bird in the box is still in defensive mode.
Eventually, the bird outside flies off.
After short while it looks out of the hole to see what's going on.
Nothing is going on! So peace returns.