Though some bull snakes can be docile, and with some time become accustomed to handling, most are quite defensive.

When bullsnakes detect live objects too big to be prey, they seem to perceive the object as a predator and take defensive action.
Their first action is to remain quiet, not moving.
Then, when they feel they are able to move away from the object, their next line of defense is to move away as quickly as possible.
Bullsnakes, however, are not fast movers and often must take other defensive actions.
When threatened by anything as large as a human, a bullsnake's next defensive action is to rear up and make itself look as large as possible, while at the same time hissing at the perceived threat.
It typically then begins lunging and retreating at the same time to escape.

Bullsnakes can sometimes be mistaken for rattlesnakes and killed.
Owing to its coloration, dorsal pattern, and semikeeled scalation, it superficially resembles the western diamondback rattler (Crotalus atrox), which is also common within the same range.
The bullsnake capitalizes on this similarity by performing an impressive rattlesnake impression when threatened.
First, it hisses, or forcibly exhales through a glottis or extension of the windpipe.
The end of the glottis is covered by a piece of cartilage known as the epiglottis, which flaps back and forth when air is exhaled from the right lung, producing a convincing rattling sound.
It also adopts a rattlesnake-like "S-curve" body posture as though about to strike.
It commonly vibrates its tail rapidly in brush or leaves, and flattens its head to resemble the characteristic triangular shape of the rattlesnake.
These defensive behaviors are meant to scare away threats, however, and not to sound an attack.

In contrast to rattlesnakes, which usually keep their tails elevated to sound the most efficient rattle, bullsnakes tend to keep their tails in contact with the ground, where they can be vibrated against leaves, for example.
Though some bull snakes can be docile, and with some time become accustomed to handling, most are quite defensive.
When bullsnakes detect live objects too big to be prey, they seem to perceive the object as a predator and take defensive action. Their first action is to remain quiet, not moving. Then, when they feel they are able to move away from the object, their next line of defense is to move away as quickly as possible. Bullsnakes, however, are not fast movers and often must take other defensive actions. When threatened by anything as large as a human, a bullsnake's next defensive action is to rear up and make itself look as large as possible, while at the same time hissing at the perceived threat. It typically then begins lunging and retreating at the same time to escape.
Bullsnakes can sometimes be mistaken for rattlesnakes and killed. Owing to its coloration, dorsal pattern, and semikeeled scalation, it superficially resembles the western diamondback rattler (Crotalus atrox), which is also common within the same range. The bullsnake capitalizes on this similarity by performing an impressive rattlesnake impression when threatened. First, it hisses, or forcibly exhales through a glottis or extension of the windpipe. The end of the glottis is covered by a piece of cartilage known as the epiglottis, which flaps back and forth when air is exhaled from the right lung, producing a convincing rattling sound. It also adopts a rattlesnake-like "S-curve" body posture as though about to strike. It commonly vibrates its tail rapidly in brush or leaves, and flattens its head to resemble the characteristic triangular shape of the rattlesnake. These defensive behaviors are meant to scare away threats, however, and not to sound an attack.
In contrast to rattlesnakes, which usually keep their tails elevated to sound the most efficient rattle, bullsnakes tend to keep their tails in contact with the ground, where they can be vibrated against leaves, for example.
Bullsnake