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Natural Highlights: Swamp Snakes

Of the 23 or so species of snakes known to occur in this area, 7 are considered water snakes, adapted to spending their lives in and around water.

Water snakes are very common in the Wolf River, especially in the unchannelized upper Wolf. Their abundance is an important indicator of the wildness of the Ghost River and other sections, adding to the beauty and adventure of paddling trips there. The Northern or Midland Watersnake (Nerodia sipedon) is probably seen more frequently than any other, though the venomous Cottonmouth or Water Moccasin (Agkistrodon piscivorus) is also quite common.  Other species include the Diamondback Watersnake, the Banded Watersnake, the Plain-bellied Watersnake, the Green Watersnake, and the Eastern Mud Snake. Except for the Cottonmouth, all of our water snakes are non-venomous, which is not to say most of them won't bite if harassed. They all make their living consuming other creatures: small fish, frogs and tadpoles, large insects, other snakes, and small birds and mammals. The Mud Snake seems to specialize on amphiumas and sirens.

            

         

  Northern Watersnake                                                      Cottonmouth

The triangular pit viper head of the Cottonmouth is one way to distinguish it from the other watersnake species, most of the time. When frightened, many of the non-venomous watersnakes can do a pretty good imitation of a Cottonmouth by flattening out their heads, a defensive adaptation.  In general, Cottonmouths appear overly bouyant when swimming, their entire body length visible on the surface of the water; the other watersnakes tend to stay mostly submerged.  Also, Cottonmouths are heavy-bodied snakes which are more likely to be found lying quietly on logs or camouflaged on the bank than in overhanging tree branches.

As the days grow short and cool, all snakes will begin to brumate (not hibernate, which is something only mammals do), crawling into burrows, beaver and muskrat lodges, or under logs or tree roots in the uplands surrounding the river and its wetlands. They  will often share quarters with other snake species and will be mostly torpid and inactive until temperatures warm in the spring.  Even in the middle of winter, however, snakes might come out and bask in a sunny spot on an occasional warm day. 

Posted by Cathy Justis at 7:40 PM