How a rat snake climbs a vertical wall?

A rat snake clmbing a wall.

A rat snake

The rat snake is an accomplished climber.

This one is showing his skill by climbing the brick side of a building.

He is apparently a young one, since he fits nicely into the grooves between the bricks.

He loves to dine on rats and mice.

The Audubon Society Encyclopedia of Animal Life reveals his special skill in climbing:

Rat snakes have weakly keeled ventral plates. At least one function of the keel is to provide a sharp corner or projection that the snake can press against bark and thus obtain better purchase. It can climb up the trunk of a large tree by wedging its body between the ridges of bark and hitching upward at least partly by means of the keeled ventrals.” 

His presence on a tree may make him the target of a flock of screaming, dive-bombing blue jays.

A trek up the side of this building will probably not end with birds or bird’s eggs on the menu, but it could provide a siesta on warm bricks.