RedDead Redemption Unusual Happening in tall trees?

i was playing RedDead redemption On singleplayer while hunting in tall trees for grizzleys at night. Something to the right of my location caught my eye between the treeline. My frist thought was a Bear but after being shot this thing veered left and came at me in a matter of secodns. it was the fastsest thing i ever hunted, faster than a cougar. After Taking a semi shotgun blast to the leg it killed me and my horse in one hit. I went back looking for it again but havnt been able to find it. Its goign on 2 hours now and no luck. anyone have any clue what it was i read on wiki that there may be an easter egg werewolf and might have found it? may be a glitch too but ive never seen anything like this before.

http://i608.photobucket.com/albums/tt164/Bman231/w... <---the link provides the pic in which i labeled it werewolf. i hope R star has this easter egg as a werewolf and not a glitch liek san andreas has big foot, can anyone else confirm this? my friend saw soemthing liek it too but it ran off too fast for him to kill.