Whooping in Snohomish County, Washington

On a hike from Barlow Pass through Monte Cristo up to Silverlake my girlfriend and I had a strange experience. On the lower part of poodle dog pass there is a set of steep switchbacks in the trail. It was logged a few years before but was too steep to see above us on the trail. All of a sudden verything got real quiet. All the birds stopped singing. Then we heard a whooping noise. It started about 100 yards away above us on the hillside. We stopped and listened. The noise continued about every 2 minutes and got closer and closer. Once it got within about 30 yards away directly above us, it was really loud. We could smell something that was like a dirty wet dog smell. I pulled my sidearm. I did not remember ever hearing anything like this before and was concerned we were about to be attacked by something big. We sat waiting on the trail for about 5 minutes after the last noise. I was scanning the hillside above us but could not see or hear any movement. The birds started singing again and the smell went away. My girlfriend has less time in the woods than I so she asked me what that was. I calmly stated it was "just a bigfoot, but he's gone now". I was kind of kidding to make her relax but not sure I was wrong. We slowly continued up the trail. It was dry hard gravel and dirt so there were no tracks. We did not see anything so we went on up to the lake and had a good time. Once we got home I went to the BFRO site and listened to the sound recordings. One of them was exactly what we heard. The hairs on my neck stood up. What ever made that noise in the recording was what we heard. Also I thought the smell could be some type of plant that smelled like a dog and that was why it was called poodle dog pass. I looked around at the plants but did not see any that smelled like that wet dog. At the top of the trail near the lake there is some stinky plants but they are different than what we smelled.