This week we're visiting the Holkham Estate in Norfolk. Joe Crowley witnesses the awesome spectacle of thousands of overwintering pink footed geese leaving their roost. Matt Baker unearths the remarkable life buried deep in long-abandoned ponds and discovers which exotic creatures have a penchant for a certain type of oak. Charlotte investigates why the UK's sugar beet farmers are facing an uncertain future, and it's a visit to the vet for Adam's trusty sheepdog Peg. Could her working days be numbered?