Timber Rattlesnake

Viperidae (venomous snakes) in the order Squamata (lizards and snakes)

Our largest venomous snake. Generally tan or yellowish-tan, the timber rattlesnake has markings along the back that are dark brown and change from blotches on the neck to bands near the tail. Often, a dark line extends from the eye along the angle of the jaw, and there is a rust-colored stripe down the back. It has a large rattle at the end of its tail. Like all venomous snakes in Missouri, rattlesnakes have a hole between the nostril and the eye, and the pupils are vertical, like a cat’s.

Length: 3–5 feet.
Habitat and conservation: 
This rattlesnake lives on rocky, wooded hillsides and mature forests. In Missouri, it tends to congregate in selected south-facing rocky areas where it overwinters.
Timber rattlesnakes eat a variety of rodents and also small rabbits. They use their venom so that they can take their prey without a struggle. A secondary use for the venom is for self-defense.
Distribution in Missouri: 
Formerly statewide, but now eliminated from a number of counties.
Habitat loss and persecution have caused a continuous decline of this species in our state.
Life cycle: 
Active from April into early October. They bask on sunny rocks in spring and autumn. In summer they are mostly nocturnal. Courtship and mating occurs soon after they emerge from overwintering dens, or in late summer. Females produce a litter of young every other year, beginning in their fourth or fifth year of life. Birthing is in late summer into early October. Litters average about 8 or 9 young. Newborns have one rattle segment. Each time they shed their skin, a new segment is created.
Human connections: 
Poisonous snakes play an important role in many human religions. Also, the fear and curiosity that venomous animals inspire often lead us to look more closely at the natural world as a whole. Many naturalists, professional and amateur, got their start by learning about such awe-inspiring creatures.
Ecosystem connections: 
As predators of rodents and small rabbits, rattlesnakes serve a vital role in controlling the populations of those prolific breeders. Yet they, too, fall prey to other predators such as hawks, owls, minks, skunks and herons. Their young are especially vulnerable to predation.