Whistling is a feature introduced in Red Dead Redemption. It allows the player to call his or her mount over from any distance by pressing up on the d-pad on the controller. Players are able to do this in both singleplayer and in certain multiplayer modes. If the player's mount dies, whistling will cause the mount to respawn, but there is a short delay before this is allowed.
If the player first uses a horse deed from Marston's inventory, then a horse of that breed will respond to the whistle; otherwise a random two-star horse will spawn.
While riding on a mount behind a herd of cattle, whistling can also be used to motivate the cattle to move faster. In this scenario the action alternates between whistling and calling out other forms of encouragement.
- If a Dog is near the player at the time the player whistles, the dog will walk up to and follow the player. The dog can be used for hunting dangerous animals, but it's usually not worth the effort.
- If you whistle near a Stagecoache while it's moving they will stop and let you hop on it. If it is already stopped, the driver will just say "Hop on board." Or something along that. This always happens if you whistle for your horse outside the Armadillo safehouse as the stagecoach is so close, just behind the freight station across the road.
- The random encounter where an NPC asks for a ride, then steals your horse, can be quickly resolved simply by whistling, upon where the horse will buck the thief off, and return to you, provided Marston has bonded sufficiently with that particular horse.