One very active fox

Work-wise, January was a very quiet month. I was often finished by lunchtime. At 4.50 p.m. German time, I then switched on ITV3 via the Internet and then settled down to an evening of crime series, always kicking off with Midsomer Murders. 

Now when I was growing up, I never ever ever heard a fox. However, every time there is a night-time scene on Midsomer Murders, you hear the cries of a fox.

What I wonder is this: do they just play a recording of a fox to make the scene a bit more interesting or is there one very star-struck fox in the area who, whenever he or she sees a camera crew at night, rushes over to take part in the filming?