Even if you are wearing ghille staying near it too long will cause it to agro,so I suggest setting a timer for about 2 mins after its feed time becomes more frequent due to the initial wait time of 5+ minutes on high lvls.
For beginners these things will spot you in a split of a second so don’t even think of going up to it with a stimberry in your hot bar. Instead, get a ghille suit and sneak behind it and feed it a beer! Don’t use stimberries it is pain And time consuming unless you have a bush of stimberries. They eat berries after they are tamed though. Not beer.