Northern Brown Snake

Overview:

Scientific Name: Storeria dekayi dekayi
Size: 9 – 20.7” but rarely larger than 15” (adult total length)
Status: Locally common but less so to the north.

Brown Snake

Habitat:

Occupy a variety of habitats, from dense woods to open prairies, meadows, and marshes. Prefer moist soils but sometimes found in drier areas such as hillsides and pine woods. Tolerates human habitat alteration and can occupy agricultural, urban, and suburban lands.

Adult Coloration:

Brown, grayish brown, or tan, with a wide lighter brown dorsal stripe bordered on each side by a row of dark spots. Sometimes dark spots scattered on sides. Head is dark, often with dark bar at back of jaw, dark spot or two under the eye, and a dark blotch on each side of neck. Belly can be cream to buff or light pink, sometimes with small dark spots at edges.

Adult Characteristics:

Small snake with small head, keeled (ridged) scales, and divided anal plate. Males slightly smaller than females with shorter tails.

Juvenile Characteristics:

Newborns can be 2.7 – 4.6” in length and are darker than adults with a light band around the neck.

Scale Count:

Usually 17 scale rows at midbody

Species Confused With:

Northern Red-bellied snakes are similarly small, but usually have red or pink bellies and 5 scale rows at midbody. Northern Ring-necked Snakes are also small, but these lack spots or stripes on the back and have yellow or orange bellies and unkeeled scales. Garter snakes have side stripes and an undivided anal plate.

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.