Black-necked Garter Snake

There are three recognized subspecies of the blackneck garter snake, two of which, Thamnophis cyrtopsis cyrtopsis and Thamnophis cyrtopsis ocellatus, are described below.

Western blackneck garter snake. Thamnophis cyrtopsis cyrtopsis (Kennicott, 1860) The western blackneck garter snake may attain 107 cm (42 inches) in total length. The snake is colored dark olive with an orange-yellow stripe that is displayed on the middle of the body from the top while the underside is usually a cream or light shade of gray. The western blackneck is a water snake that lives near rivers, swims, and eats small fish and tadpoles.

Eastern blackneck garter snake. Thamnophis cyrtopsis ocellatus (Cope, 1880) The eastern blackneck garter snake is smaller than the western blackneck garter snake, with an average total length of less than 51 cm (20 inches). It is frequently found on dry land near a water source rather than in water. It displays three light stripes on a dark-colored body with uniform orange and orange-yellow spreading throughout.

The blackneck garter snake can be found in southeastern and central Arizona, parts of the southwestern United States, Mexico and Guatemala.

It is active during the day and during twilight activities, and occasionally at night, hibernating from late fall to winter and mating in late spring or summer.