Knocks heard from Great Croton Swamp south of Pawling witnessed in Putnam County, New York

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I was having a small camp fire last night alone with my small dog who at the time was sleeping. First there was something moving through the wooded area to my left. Sounded like it was on two feet and moving towards some neighbors houses. Wasn't alarmed by this, although it was dark and there was no flashlight the neighbors do walk through there from time to time. My dog wasn't alerted at all. This part of the incident may be just coincidental but it's what happened next that I'm curious about. About five to ten minutes later to the left of me way off in the distance there was an obvious wood knock then immediately to the right of me in the distance but in that direction is the Great Croton Swamp was a reply wood knock and then immediately after that another from the left. Then nothing. I've never heard anything like that before. It was about 11pm and the neighborhood was quiet and in my opinion it was an obvious call and response. Are wood knocks usually so instantaneous or do the...