Now is a great time for a walk on a moonlit, windless night over the heath as nightjars are back on their breeding territories.
They are invisible during the day when they rest brilliantly camouflaged on the ground or motionless on a tree branch. But come nightfall they take to the wing to hunt insects.
If you are lucky enough to be close to where one is flying you may just make out a shape similar to a kestrel or cuckoo, with pointed wings, a long tail and perhaps even the white patches in the wings.
Much more likely though is that you will hear the rise and fall of a sustained ‘churring’ made by males from a perch on a small tree or post.