Down by the shore on the croft, where the woods go right down to the sea, there is an old aspen tree with a hollow branch. It's an old favourite.
Last weekend, on a whim, I peered into the hole. To my amazement, inside was a curled up butterfish.
Who put it there? Will they come back and get it?
I've been away this week, but Bill's been checking the fish almost daily. It's still there.
An otter, perhaps?
I imagine her, full after an excellent day's fishing, unable to resist catching just one more. Then she carried it up across the rocks and stashed it in this hole for a hungrier day.
Will she come back for it? Is her memory that good? Or has she forgotten that she put it there?
It's mysteries like this that make the natural world so endlessly fascinating.