Butler’s Garter Snake

Overview:

Scientific Name: Thamnophis butleri
Size: 15 – 29” (adult total length)
Status: Species of Special Concern and Species of Greatest Conservation Need

Habitat:

Prefers wet meadows and prairies, borders of marshy ponds and lakes, and other moist grassy areas. Will also inhabit vacant urban and suburban areas.

Adult Coloration:

Three conspicuous yellow or orange stripes on black, brown, or olive brown background, sometimes with two rows of dark spots between the stripes. Stripes on scale row 3 and adjacent halves of scale rows 2 and 4 toward the head. Head black or olive often with two small yellow spots on the large scales at the back. Labial scales (along the mouth) are yellow, sometimes with brown shading or speckles. Belly pale green or yellow with brown edging and often dark spots along the edges.

Adult Characteristics:

Rather small and stout snake with keeled (ridged) scales and a single anal plate. Head is same size as or barely wider than neck. Males smaller and more slender with longer tails.

Juvenile Characteristics:

Newborns range from 5 – 7.3” in length. Same coloration as adults but with proportionately larger heads.

Scale Count:

19 scale rows at midbody

Species Confused With:

Ribbon snakes and other garter snakes have relatively larger, longer heads. Eastern Garter Snakes have side stripes on scale rows 2 and 3.

References:

Amphibians and Reptiles of the Great Lakes Region by Jim Harding
Harding, J.H. and J.A. Holman. 2006. Michigan Snakes. MSU Extension Ext. Bulletin E-2000,74 pp. [revised].
Ruthven, A. G., H. B. T. Gaige, et al. 1912. The herpetology of Michigan, by Alexander B. Ruthven. Crystal Thompson and Helen Thompson; Memoranda towards a bibliography of the archaeology of Michigan, by Harlan I. Smith; prepared under the direction of Alexander G. Ruthven. Lansing, Mich., Wynkoop Hallenbeck Crawford, State Printers.
Holman, J. A. 2012. The Amphibians and Reptiles of Michigan: A Quaternary and Recent Faunal Adventure. Detroit, Mich., Wayne State University Press.
Conant, R., and Collins, J. T. 1998. Reptiles and Amphibians: Eastern, Central North America. Houghton Mifflin Harcourt Press.