Thank you to Mr & Mrs Ginsler who did some research on the noise that they heard a few weeks ago in the middle of the night at Arowhon Pines. All the guests at the resort heard it again the other night, loud and clear!
Mrs Ginsler passed along a UTUBE video which captures the sound. Very eerie. It seems like it is either a fox in distress or a male fox mating call.
Here is the link: http://www.youtube.com/watch?v=0cPg7_nyoBc&feature=related
(the video quality it not great, but the sound is perfect)
Thanks again Mrs Ginsler! See you next year!