The dark brown bird box hung on the side of the static caravan for years. I often saw it as I walked past. One spring, blue tits raised a family in it. Then the caravan changed owners and the newbies slung the box away. I found it that winter in a bramble patch. Bringing it home, I put the bird house up in our hedge at head height. Since then, we’ve had front-row seats as generations of blue tits and tree sparrows have laid eggs and reared young in the rescued wooden lodging.