[3] The rattle consists of a series of loosely interlocking hollow shells, each of which was at one point the scale covering the tip of the tail.

In most other snakes, the tail tip, or terminal spine, is cone-shaped, hardly any thicker than the rest of the skin, and is shed along with it at each successive molt.

In this case, the end scale, or "button", is much thicker and shaped like a bulb, with one or two annular constrictions to prevent it from falling off.

This process continues so the succession of molts produces an appendage consisting of a number of interlocking segments that make an audible noise when vibrated.

Strike distance depends not just on the snake’s size, but also on many other factors, including its species, the position of its body, and its degree of agitation.

These include other snakes, such as kingsnakes (Lampropeltis), coachwhips (Masticophis), indigo snakes (Drymarchon), and racers (Coluber); birds, such as hawks, eagles, owls, roadrunners, and ravens; and mammals, such as cats, coyotes, foxes, wildcats, badgers, skunks, and pigs.

Two cases were reported in which dead hawks found near venomous snakes had suffered hemorrhage and gangrenous necrosis due to snakebite.

Females at an age of 26 months undergo vitellogenesis as they enter their third hibernation,[13] mate the following spring, and give birth later in September or October.

[14] Second, the platelet antagonist crotalin creates a severe bleeding effect as it binds to the surface proteins, blocking aggregation.