Screaming or howling in Marion County, Oregon

Nov 13th, 2006: 9:00 pm, dark, rainy and cold. My husband and I had just put our oldest son to bed, and were settling down to watch TV in our living room. My husband heard "someone" screaming "bizarrely", very loud far off across our lake, so he opened our back sliding door to get a better listen. That was when we both heard a, maybe 3 at a time, organized pattern of what can only be described as roaring screams. We knew immediately they were not human. I had heard the Klamath audio before and this made my hair stand on end because it was exactly the same. This animal was closer, just across a 6 acre or so lake/pond. We heard probably a total of 4, 3-at-a-time, scream patterns. The individual screams were alarmed, but not frantic. It seemed to be almost 'responding' to dogs barking. The 'runs' were all about .5 - 1 second apart. The interval in between patterns was probably 1 minute or so. All was quiet for about 3 minutes and somewhere in the dark across the lake we heard something very, very large and strong tussle successfully with a dog. At the end of the tussle the dog let out a sharp yelp and we heard a thud. At that point we (I flipped out) shut the door, locked all the doors, sawed a serious dowel for our back slider, turned on our kids white noise machines and went to listen from another part of the house. We heard a few more screams but it sounded farther away at this point and then seemed to go away. Whatever tangled with that dog was extremely fast, extremely large and very strong. Based on what we heard, it sounded like the creature must have either approached or walked past a tied up dog. We heard a quiet small scuffle probably as the dog tried to bite it. Then an enormous amount of thudding, bushes rustling, and a loud pained yelp and a thud. All was quiet after that and we heard some quiet splashing in the lake. The splashing could have been disturbed waterfowl, however. It was pitch black and we were looking out our back sliding doorway into the blackness basically just trying to listen when this occurred. The tangle with the dog occurred about 3 minutes after we heard the vocalization pattern. In total, the vocal pattern seemed to be moving slowly from the northwest end of the lake to the northeast end, where we believe the dog incident occured. I have a BS in zoology from the University of Washington and a considerable amount of outdoors experience. I have heard all different types of animal calls, screams, etc... I'm even quite good at discerning the subtle differences between a Beluga whale click and a porpoise call. I have perfect pitch and a well trained ear from years of classical voice training. This was most certainly a primate type call, almost with a Siamang type quality to it. It was most definitely not human, and I'm certain it was not any other animal common around our area (coyote, deer screaming in pain, rabbit, fox, racoon, other). It was extremely similar to the Klamath falls recording only louder and closer, and it scared me more than anything I've ever encountered. My husband and I discussed our observations at length. There is honestly no other explanation for this type of call and activity, though we understand how rare and extraordinary this must be because we live in a settled area near freeways and quite honestly we've never really considered "bigfoot" before much more than "what a neat theory!" Let me just state again that this was not human. Not even close. Even a human trying to imitate something like that would have had a 'narrower', more nasal sound as a human just doesn't have the head/throat size to accomplish such volume and tone. Further, it had a squeal and roar quality at the same time, like nothing I've ever heard except the various recordings, in particular the Klamath. Also a human scream would have had some identifiable emotion to it (drunk, scared, angry etc...) as humans we're quite good at picking up on tones of other humans. This had none of that. It was entirely foreign to us. Update: this morning as I look through my binoculars across the lake, exactly where we heard the dog tussle incident, the neighbor's canoe dock is destroyed. It looks to just be made of plywood but it's cracked and half-sunk as far as I can tell