Screaming or howling in Fresno County, California

It was late October 2006. My hunting partner and I were deer hunting near Heart Lake, which is located off the John Muir Trail behind Florence Lake. We'd been back there for almost a week looking for the elusive Big Daddy Buck that we've hunted religiously for the last three years. We were high up on this ridge just before nightfall. We were hiking back to our base camp and heard a loud bellowing howl that sent a shiver down our spines. We looked at each other with confused looks on our faces, not knowing what that sound was. We decided to hurry back to camp, but we heard another howl, but closer this time. We saw Big Daddy Buck running down the opposite ridge side, and busting through brush, not caring if hunters spotted him. Then again, we heard that bellowing howl, and saw on top of the ridge a dark silhouette that looked like a bear standing on its hind feet. I brought my rifle scope to my eye to take aim on this so-called bear. As I looked through the scope, I realized it was no bear. I thought it could have been a really tall man in some kind of camouflage suit, but it looked like no man that I have ever seen. It ran down the hill and disappeared into the brush, like it was chasing the deer. So we decided to go and track down this creature. Once we arrived at where it was standing, there was a footprint in the dirt that made my footprint look like a child's footprint. It was four times the size of mine. We never saw the creature again and never heard that howl, but then again, I've never gone back since then.