Make sure the bird box is at least 6 ft above ground level on a wall that a cat cannot climb.
Don't put them in trees, as cats can get to them easily there.
Don't have a landing perch on them, as the magpies will be able to get at the young then.
Yes, a camera is a good way of keeping track on the birds in the nesting box.
Don't place the box in direct sunlight, as it can get so warm the chicks die if you do.
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