Seeing a flock of black and white striped, powder puff pink flanked long-tailed tits bouncing through the grey and brown winter landscape is a cheering sight. Scruffy and bandit faced they are often heard before they are seen with piping calls to keep the flock together. Charging around in family groups these diminutive birds will spend the coldest winter nights roosting together, lined up along a branch jostling for the best position. Naturalist John Walters takes Chris Sperring to the southern fringes of Dartmoor to introduce him to one particular family group.