The beaching of twenty six pilot whales in Scotland's Firth of Forth made headlines, and highlighted the importance attached by many of us to the creatures which live, largely unobserved, in our seas. In Open Country this week, Richard Uridge travels further north, to the Moray Firth, to test the health of its mammal populations, and to try to fathom what it is about these creatures which strikes such a chord in humans.