Springwatch is back for its second week at the National Trust's Sherborne Estate in Gloucestershire. Chris Packham, Michaela Strachan and Gillian Burke bring updates on the dramatic events that unfolded over the weekend. The blue tits were due to fledge, but did they get out before the woodpecker found them? And there was high drama in the swallows' nest when a rouge jackdaw came to visit. Meanwhile Martin Hughes-Games has travelled to Scotland to track down some ecosystem engineers - a population of beavers. Staying north of the border, we also meet a very special family of pine martens hiding in an attic. There is new science showing how the quality of a dipper's song is related to the quality of its territory, and we drop in on an eight-legged love story, playing out on a small pool on a heath.