Surveying eastern indigo snake habitats

Hello everyone! My name is Roxanne Buckman, and I am a keeper here at Zoo Atlanta in our Ambassador Animals Department. This past year I was the recipient of the Mickelberg Field Conservation Grant, which funded my trip to southern Georgia to participate in the Orianne Society’s field surveys for eastern indigo snakes. The Orianne Society is a conservation organization that focuses on reptiles and amphibians in the southeastern United States. Each winter, from about November through February, researchers at the Longleaf Stewardship Center outside of Lumber City, Georgia, survey indigo snake habitats to gain valuable information about the snake populations in southern Georgia and the health of the individuals. They have around 70 sites total that they survey on a three-year rotation. 

I was able to spend a full week with the Orianne team, and we surveyed six different sites, which were a mix of private, public, and Orianne-owned land. Each day we would load up our equipment and drive to our first site, which was sometimes up to two hours away. Our main focus was mapping gopher tortoise burrows. Like many species, eastern indigo snakes rely on gopher tortoise burrows for shelter. We had GPS data of burrow locations from the last time the sites were surveyed back in 2021. It was our job to see if those burrows were still in use, and to map any new burrows that had appeared since then. All the while we were looking for signs of recent snake activity, and of course, actual snakes! We spread out and methodically covered acres of land each day, walking miles and miles back and forth over the areas.  

The area was beautiful, but many sites were fire suppressed, meaning they had not been allowed to burn naturally. These fire suppressed habitats were overgrown and covered in thick brambles. Not only did this mean the habitat was no longer suitable for gopher tortoises and indigo snakes, but it meant we were fighting our way through sharp thorns, pokey sticks, ticks, and mosquitos. It was also deer hunting season, so we had to be careful about where we were and at what time of day and wore high visibility clothing. And as if all this wasn’t enough, this area of Georgia had been hit hard by the hurricanes earlier in the fall. Many of the sites had a lot of downed trees and some of the habitat areas were severely flooded and altered.  

Despite all this, we were able to get three different indigo snakes in hand over the course of the week. That may not sound like much, but indigo snakes have large territories and are solitary outside of breeding, so even though we were covering large areas, our chances of encountering snakes were still fairly low. Three individuals in hand was more than I expected for my first survey. Getting snakes in hand is always exciting, because that’s how we really start to gather information about the population.  

So how does one get one of the largest species of snake in North America in hand? It’s actually pretty simple- we just pick them up! They are surprisingly amenable to the entire process. None of the snakes we handled displayed any signs of aggression, and getting a hold of them was as simple as walking over and picking it up. They were of course unaccustomed to being handled and were a bit wiggly, and this was done by professionals with years of experience handling wild snakes (we would not recommend walking up to any snake in the wild and handling it without this type of experience).  

Each snake that is caught undergoes a full exam, and many different types of samples are taken. To start, the snakes are weighed, measured, and checked for PIT tags. PIT tags are small subcutaneous transponders which will give information on that individual when scanned. It works just like the microchips you can get for your pets. If a snake hasn’t been tagged, the field technicians will implant one using a hypodermic needle. Samples are then taken. The snake’s body, head, and cloaca are swabbed, and small clippings of scales are taken for DNA. These different samples will later be screened to look for signs of disease and parasites. After the exam is complete and the samples are taken, the snake is released to a burrow so it can recuperate.  

These exams give researchers a lot of important information about the species. First, the number of snakes found year to year and the areas they are found in, along with how many recaptures vs. newly found snakes there are, can help scientists determine the approximate population numbers. These numbers can tell us if eastern indigo snakes are thriving, or if they are becoming endangered. Secondly, the samples taken help scientists to monitor diseases that affect not only indigo snakes, but many different snake species. Namely, snake fungal disease and snake lung worm. Snake fungal disease is a fungal infection that can cause lesions on snakes, leading to secondary health issues and even death. Snake lung worm is a small parasitic crustacean that embeds in the respiratory tract of snakes and can affect their ability to breathe and eat, especially in smaller snake species. Sampling done by Orianne can be compiled with information from other agencies all over the country and allow the spread of these diseases and their environmental impacts to be understood and monitored.  

While the entire week was a wealth of new information and experiences, my favorite part of my time with the Orianne team was when we captured the third snake. We were in a wooded area, and like all the times before, were fairly spread out trying to cover ground in a systematic manner so that we didn’t miss any burrows. As I was walking towards one of the burrows mapped on my GPS, I saw a large black snake coiled up on the ground about 10 feet away. I called out to the field technicians, and with their go ahead I was able to get ahold of the snake. During our examination of it, we determined that it was a male about 6 feet long, and it had not yet been tagged! This was exciting because, as the one who found and captured the snake, I would get to name it for the records associated with the tag number. That night on the phone I consulted with my 11-year-old son, who was adamant that the snake should be named Larry. So if you ever find yourself surveying for eastern indigo snakes in southern Georgia and you come across Larry, tell him Roxanne says hi!