Chris Packham and David Tipling watch a male nightjar on its roost. The female is on the nest somewhere nearby. The male will return to the same roost regularly - he has several roosts in the area. He is fantastically well camouflaged. As twilight comes they head out onto the heath to watch the male's activity. Nightjars are usually elusive, but David has been photographing this one for three years and gradually been able to get closer and closer. Jazz music can be heard from the nearby campsite, but Chris hopes the nightjar will drown it out. The male arrives and calls to the female. His beak looks small but can open really wide to catch insects. Nightjars are crepuscular - they come out at dusk and dawn. They can fly several kilometres in search of food.