The Bluetit Pitty

They cannot see me,
As small as I am,
But I can see them,
The face of cruel man.

"They cannot see me"
Instead of saying
"As small as I am"
I think it would draw more attention to point out
They cannot see me
and the mention how bright and beautiful the bird is instead of small... perhaps:

They cannot see me
Though I be bright and pretty
For they are obsessed
with growing their city