Constrictor snakes usually are not aggressive and flee when confronted. They hunt for food but do not attempt to make a meal out of any creature that is too large to constrict.
Skills: Snakes have a +4 racial bonus on Hide, Listen, and Spot checks and a +8 racial bonus on Balance and Climb checks. A snake can always choose to take 10 on a Climb check, even if rushed or threatened. Snakes use either their Strength modifier or Dexterity modifier for Climb checks, whichever is higher. A snake has a +8 racial bonus on any Swim check to perform some special action or avoid a hazard. It can always choose to take 10 on a Swim check, even if distracted or endangered. It can use the run action while swimming, provided it swims in a straight line.

Constrictor snakes hunt by grabbing prey with their mouths and then squeezing it with their powerful bodies.
Constrict (Ex): On a successful grapple check, a constrictor snake deals 1d3+4 points of damage.
Improved Grab (Ex): To use this ability, a constrictor snake must hit with its bite attack. It can then attempt to start a grapple as a free action without provoking an attack of opportunity. If it wins the grapple check, it establishes a hold and can constrict.
SEE WIKIPEDIA ENTRY: Snake

---

System Reference Document -> List of Creatures (SRD)