Documentary series. A guide to the best places in Britain to see wildlife in autumn. Chris Packham visits Aberdeenshire to see tens of thousands of Icelandic geese take their holidays on the Loch of Strathbeg. Sanjida O'Connell watches leaping salmon migrating up the River Tweed. And Mike Dilger is at Slapton Ley in Devon for an iconic sign of autumn - the starling roost.