Whooping in Jasper County, Texas

I [work] in Jasper County, Texas. On Thursday August 4, 2005, [in the early evening] I was walking [outdoors on company property surrounded by the Big Thicket]. There was some rustling in the underbrush about thirty yards off to the left side of the dirt road which I was travelling down. Shortly after hearing the rustling I began to smell what seemed like a mixture of a skunk and strong coffee mixed with kind of like a dead fish smell. At first I thought that it might have been some wild hogs bedding down for the evening, so I stopped to listen for anything that might have indicated piglets since wild sows are dangerous if they are protecting their young. After about thirty to forty-five seconds, the rustling around stopped. I couldn't see into the brush, but I felt like whatever was in there was watching me. Not wanting to be the focus of a hog charge, I hollered in hopes that I would scare off whatever it was in the brush. After not getting any response, I figured that whatever it was had left, so I resumed [what I was doing]. I had to go down to a gate and turn around. When I passed the spot where I had my encounter, I heard a whoo--whoo--whooping sound coming from behind me. It was quiet at first then it got louder as I got farther away. I was puzzled as to what could make that sound. I am an experienced deerhunter, and I have never heard that sound before. It sounded kind of like a howler monkey. In fact that's what I would have thought that it was if I didn't know any better. About two and a half hours later [at a different location] I smelled the same smell. I have smelled that smell there several times after dark. I would like for my specifics to be kept confidential, as well as my job title.