Conspirosy

I've taken down almost every legendary animal with the same 3 poison arrows, since you can pick them back up after. 1 well placed poison arrow in head or neck will slow it down and cause it to collapse in agony. Then just approach and put it out of its misery. I needed 4 arrows to take out the wolf and it nearly killed me. However, poison arrows didn't help with the gator and bear. I kept firing at its face until it tore me apart. Should I just use rolling block rifle for those?