Migratory Snakes

The changing seasons have the snakes on the move, heading for cover, returning to dens where they will overwinter (this is called “ingress”, i.e., the act of going in). Of our Coastal Plain snakes, adult Eastern Indigo Snakes disperse around April to May, up to one to three or more miles from Gopher Tortoise colonies in sandhills. Retracing their slitherings, they return to the same gopher ridges in October to November.

In southern Missouri and Illinois, one can observe snakes in large numbers this time of year as they move from oak bottoms and swamps upslope to sunny ledges of limestone/sandstone. When conditions are appropriate, one can observe snakes in considerable numbers on a September or October afternoon (the local fauna boasting over two dozen species of snakes) at LaRue Pine Hills Ecological Area in Shawnee National Forest, IL—a.k.a. “Snake Road”, where a primitive gravel lane separates a large Big Muddy River oxbow swamp from precipitous, towering bluffs from which one can gaze west over the Mississippi into Missouri—and similar sites. Constituents of snake dens here include serpents long and slender (Rough Greensnakes, Western Ribbon Snakes), constrictors like black ratsnakes, black kingsnakes and red milksnakes; racers; and that marvelous triumvirate of southern Illinois vipers (Western Cottonmouths, Copperheads, Timber Rattlesnake).