What's going on here?

We were out for a walk yesterday, to Goredale Scar in Yorkshire. It was very hot and we were relaxing before returning to the car yet  we saw near us, a tall bearded man and he had beside him, on the ground, a small ornate cage which contained a bird that was hopping about and banging its head against the cage sides and roof. Neither of us have any idea what the bird is nor why it was in such a small cage on a very hot day (27c). Any ideas?