Road Cruising for Rare Reptiles

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by Kevin Stohlgren

Driving slowly down a rural dirt road, trying to stay alert, I notice a tell-tale shape in the road. As I get closer I realize that what lies before me is none other than………a stick. This is a common theme for me as I conduct road cruising surveys in southern Georgia. Our goal is to find new locations for two rare, and possibly declining species of snake—the Southern Hognose Snake (Heterodon simus) and the Florida Pine Snake (Pituophis melanoleucus mugitus).

Southern Hognose Snakes and Florida Pine Snakes are denizens of upland, sandy habitats with open canopies and grassy groundcover, and they are rarely encountered, even by herpetologists that are specifically looking for them. This is due in part to the fact that they are highly fossorial species, meaning they spend a great deal of time underground. There is speculation that they may also be declining throughout their range from habitat loss, fragmentation and degradation, which has lead to a proposal to have them listed as a Threatened species under the Endangered Species Act.

The question is, how do you find snakes that spend most of their time underground and, when they are on the surface, sport excellent camouflage? Our answer: road cruising. Roads are a significant threat to many snakes as they serve as a source of direct mortality (road kill), but they also provide a way for herpetologists to survey for snakes. When snakes are active, they frequently have to cross the roads that we have built through their habitat. And while they are on roads, they are more visible than they would be in their natural habitats. Another benefit of road surveys is that you can also cover more ground in a vehicle than on foot. So in an effort to identify new locations for these species, we have identified roads that go through what looks like suitable habitat that we can survey.

An unfortunate reality of road cruising is seeing road-killed snakes. But even road kills can provide us valuable information, as it indicates a species is present and persisting in the area that it was found. And because a dead snake may remain on the road for hours or even days, we are more likely to encounter a dead snake than one that is quickly trying to cross. So we record all species we encounter, alive or dead.
So far we have not encountered any Southern Hognose Snakes or Florida Pine Snakes, but we have made a few good finds including all six of Georgia’s venomous species. The best encounter this fall has been a live hatchling Eastern Indigo Snake (Drymarchon couperi), which is the flagship species of the Orianne Society and one that is already listed as federally Threatened. We know little of the ecology of juvenile Eastern Indigos because they are so rarely encountered, so this find was particularly exciting.

Here is a list of the species we have encountered this fall:

Black Racer (Coluber constrictor)

Eastern Indigo Snake (Drymarchon couperi)

Eastern Hognose Snake (Heterodon platirhinos)

Eastern Kingsnake (Lampropeltis getula)

Coachwhip (Masticophis flagellum)

Rough Greensnake (Opheodrys aestivus)

Cornsnake (Pantherophis guttatus)

Gartersnake (Thamnophis sirtalis)

Copperhead (Agkistrodon contortrix)

Eastern Diamondback Rattlesnake (Crotalus adamanteus)

Timber Rattlesnake (Crotalus horridus)

Pigmy Rattlesnake (Sistrurus miliarius)

Cottonmouth (Agkistrodon piscivorus)

Coral Snake (Micrurus fulvius)