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Wednesday, August 13, 2014
Animal Connections - Eastern Indigo Snake
Eastern Indigo Snake
Drymarchon couperi, the Eastern indigo is the longest native snake in North America. Larger males can reach eight feet in length. Although it prefers tropical climates, the indigo extends its range throughout the Florida peninsula to southeastern Georgia by using the burrow holes of large animals such as the gopher tortoise (Gopherus polyphemus) during colder weather. Burrow holes are also important for indigos "shedding their skin" no matter what the latitude. And as the gopher tortoise species goes, so goes the Eastern indigo. Both are Threatened Species in at least one of the areas where they are found.
A burrow is a necessary, if temporary, shelter for this snake. It does not hibernate, but continues to hunt and feed outside the burrow throughout the year. And it dines on anything it can overpower, from fish to small mammals. It doesn't wait until its victim has expired - merely incapacitated. In short, it's not a fussy eater. It will even eat juvenile gopher tortoises (which seems a bit self-defeating). The indigo is not venomous, but it is resistant to the venom of snakes that are. An Eastern indigo can survive the bite of a copperhead or rattlesnake and subsequently consume either without ill effect. Not only is that trait advantageous, it's downright necessary because venomous snakes also take shelter in gopher tortoise burrows. There's only so much room down there...
If you've seen a picture of an indigo you might rightly wonder why it has the appellation, "indigo snake."
The scales of the snake refract sunlight to give its body a shimmery blue-black appearance, although that doesn't always show up in a photo. When seen in the shade, the iridescence is lost; and the snake looks like any other (large) black snake. The snake's taxonomic name, "Drymarchon," roughly translates into "forest ruler." Large and powerful as these animals are, it seems apt. Its other common names, "gopher snake," or "blue gopher," reflect its choice of gopher tortoise burrows for shelter.
Eastern indigos do not mature until three or four years of age - relatively late in the snake world. Females, when ready, will emit a pheromone to attract a male. If multiple males pick up on the scent then they battle for the female by intertwining their bodies trying to pin the other's head to the ground. Females lay about a dozen eggs, preferably in the shelter of an abandoned gopher tortoise burrow. The slow maturation rate of the Eastern indigo and its dependence upon the gopher tortoise for sources of shelter make resurgence of this species a complex goal. Snakes may not be on everyone's "favorites" list, but Eastern indigos, like all members of the Serpentes families, keep populations of smaller animals in check. Protecting its place in this world will involve allowing both the Eastern indigo and the gopher tortoise that benefits it sufficient habitat to survive.