Autumnwatch returns for an eight week celebration of UK wildlife. Chris Packham and Kate Humble visit the south coast to witness bird migration in action - autumn is the cue for summer visitors like swallows and martens to leave our shores as redwings, fieldfares and others arrive. Kate also reveals a real autumn screamer - the sika deer, while Chris gets up close to some spectacular spiders. In the Scottish Highlands, biologist Liz Bonnin is hoping for an encounter with the rare and elusive Scottish wildcat and closer to home Martin Hughes-Games is on the trail of the best of your stories.