Diagnosis:
HARMLESS. The Western Ribbonsnake is characterized by keeled scales, a single anal scale, a stripe on each side of the body situated on the third and fourth scale rows (counting from the belly up), upper lips without dark vertical bars, and a uniform olive-gray, dark green, or black skin color between the stripes. The stripe down the middle of the back is red, orange, or yellow and those on each side of the body are light yellow or cream. The belly is white, cream, or gray with some dark coloration along its edges. Females grow slightly larger than males.
Adults normally attain 51.0- 76.0 mm (20-30 inches) in total length. The largest specimen from Kansas is a female (FHSM 7243) from Edwards County with a total length of 101.3 cm (39½ inches) collected by James Gubanyi and Keith Coleman on 2 June 2002. The maximum length throughout the range is 126.7 cm (497⁄8 inches) (Boundy, 1995; Powell et al., 2016).
Fossil History:
Pleistocene fossil specimens are known from Meade and Jewell counties. Fossils from the Williams Local Fauna of Rice County (Pleistocene: Illinoian) (Preston 1979; Holman 1984; Holman 1995), Kanopolis Local Fauna of Ellsworth County (Pleistocene: Rancholabrean I) (Preston 1979, Holman 1972, Holman 1984; Holman 1995), Mount Scott Local Fauna of Meade County (Pleistocene: Illinoian) (Preston 1979, Holman 1987; Holman 1995), Butler Spring Local Fauna of Meade County (Pleistocene: Illinoian) (Tihen 1962; Preston 1979; Holman 1995), Cragin Quarry Local Fauna of Meade County (Pleistocene: Sangamonian) (Hay 1917; Etheridge 1958; Etheridge 1960, Tihen 1960; Tihen 1962; Brattstrom 1967; Preston 1979; Holman 1995) (species indeterminate), and Courtland Canal/Hall Ash local fauna of Jewell County (Rogers, 1982; Eshelman and Hager, 1984) are referable to this taxon.
Natural History:
This slender, nervous snake frequents the edges of swamps, marshes, lakes, streams, and rivers. It is active from March to October and is both diurnal and nocturnal depending upon prevailing temperatures. This species spends the day foraging along water-edge vegetation or basking in the sun on matted reeds and grasses. When frightened, it glides swiftly across water to escape. Gloyd (1928) found this species active and feeding on frogs at night during April in Franklin County. During winter, it retreats to burrows beneath the ground to avoid cold temperatures.
Western Ribbonsnakes mate during April and May, but courtship is unknown. Each female gives birth to young anytime from late June to September. Number of young per litter ranges from four to 28 (Fitch, 1985), with an average of twelve or thirteen. Gloyd (1928) collected a female in Franklin County which gave birth to eight young on 27 July. In Miami County, Gloyd (1932) found a female containing six well-developed young on 31 August. Collins (1974) obtained a gravid female collected in Franklin County which died on 13 August and contained twelve well-developed young.
This species feeds on small frogs, toads, salamanders, and fishes. Caldwell and Glass (1976) observed a Western Ribbonsnake eating a small Bullfrog in Woodson County. Taggart (1992) observed a Western Ribbonsnake consuming a Western Narrow-mouthed Toad in Chase County.
Predators of adult Western Ribbonsnakes include birds, mammals, and larger snakes. Young snakes are eaten by large frogs and fish (Collins, 1993).