another warbler thread eh? lol .....I'll get me coat...
I'm a bit basic with my computer and can't listen to that sound
...... however....I would go with a barn owl or short earred owl. The shorties here can call almost the same as the barn and send my dogs wild crazy when out on a midnight walk. Their call that alarms my dogs is a relativley very loud and short 2-tone burst repeated about every 15secs as they fly.
Mind...snipe can be quite alarming too!