Not sure how many people are aware of this or not, but every time you defeat an ambush by your prey they'll run off and vanish, but they actually move somewhere relatively nearby and hide in stealth.
When they retreat a little misty blood cloud will trail away from wherever they were. If you follow it and find the larger cloud they'll be stealthed inside, click on them to riposte them and get a chunk of progress towards your hunt (and work towards an achievement too) #entertainment