When I first started playing this used to drive me crazy because I didn't know what to do about it or how to prevent it. After a little trial and error I almost never run into this issue anymore.
For starters, train a couple animals to follow your hunters around. I recommend bears if you can get them since they can stun attackers, don't eat much and are pretty tanky (they can take down most predators on their own just fine). If a predator does attack a colonist they will have to deal with your pet first. This gives your pawn time to flee or attack depending on the situation
I'll leave my colonists set to flee. This is mostly so that if I have a berserk colonist, everyone will run away from them rather than attack them, potentially killing them. If I see a fleeing symbol in the colonist bar I can pause and assess the situation.
Avoid hunting small prey. If there are a small animals on the map odds are the predator will attack that rather than your colonist.
Build a perimeter wall around your base. If you have a killbox, I like to leave an open path into the box but have a wall with doors on the back side of the box. If a raid happens I can open those doors and raiders will still path into the box but this will keep animals from getting inside the base. Aside from keeping you safe from predators it keeps other animals from getting to your crops or boomrats from camping out inside your base.
As for turrets firing on predators, this is a double edged sword. If a turret could target an attacking predator what are the odds it will hit your colonist rather than the animal? If my colonist is fleeing from an attack I really don't want my own defenses to kill my colonist by mistake.
For starters, train a couple animals to follow your hunters around. I recommend bears if you can get them since they can stun attackers, don't eat much and are pretty tanky (they can take down most predators on their own just fine). If a predator does attack a colonist they will have to deal with your pet first. This gives your pawn time to flee or attack depending on the situation
I'll leave my colonists set to flee. This is mostly so that if I have a berserk colonist, everyone will run away from them rather than attack them, potentially killing them. If I see a fleeing symbol in the colonist bar I can pause and assess the situation.
Avoid hunting small prey. If there are a small animals on the map odds are the predator will attack that rather than your colonist.
Build a perimeter wall around your base. If you have a killbox, I like to leave an open path into the box but have a wall with doors on the back side of the box. If a raid happens I can open those doors and raiders will still path into the box but this will keep animals from getting inside the base. Aside from keeping you safe from predators it keeps other animals from getting to your crops or boomrats from camping out inside your base.
As for turrets firing on predators, this is a double edged sword. If a turret could target an attacking predator what are the odds it will hit your colonist rather than the animal? If my colonist is fleeing from an attack I really don't want my own defenses to kill my colonist by mistake.