The sounds are coming from some kind of Herons or cranes.
First time I heard it, I was like, WTH??! I pictured some kind of rabid bobcat with his tail in a bear trap...
We went outside with my high power flashlight and we could see the birds in the trees. We see them during the daylight hours, but they act more civilized then.
http://i.pbase.com/u30/dlee/upload/1...lake018PSE.jpg
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