A fox hunting

During my last polar bear tour based in Churchill, Manitoba, Canada, we came upon this red fox who was hunting for mice. I told my group to quickly switch to a fast shutter speed because foxes use a technique in which they'll jump in the air and then pounce on the prey. Within a few minutes, the fox did exactly that and the fast shutter enabled us to freeze the action. In a picture like this, anything less than tack sharp ruins the shot. For wildlife -- not birds -- 1/1250th of a second will freeze pretty much any action sequence. The camera settings were 1/1250, f/10, and 400 ISO. I used a Canon 100-500mm zoom plus a 1.4x teleconverter, giving me 700mm of focal length.