Wednesday, June 16, 2010
Big Blue Returns to Alabama
The year was 1954. Marilyn Monroe married Joe DiMaggio, Great Britain ended the food rationing program begun during World War II, and it was the last time a free-roaming and wild indigo snake was ever seen in Alabama. Indigo snakes once ranged throughout the southeastern United States from Georgia to Mississippi, crawling around clumps of wiregrass within longleaf pine forests, taking refuge within gopher tortoise burrows, and chowing down on just about anything they could fit into their mouths, including rattlesnakes. Today however, they’re thought to be gone from Mississippi and Alabama and restricted to isolated patches in Georgia and Florida.
Over the last few decades, the once expansive and continuous longleaf pine forest has been decimated and fragmented due to conversion to agriculture (among other land uses) and road construction. Due to frequent lightning strikes, longleaf pine forests once burned about every three years; the trees and plants typical of this forest were adapted to this disturbance and thrived. When the forest became fragmented, burns were no longer able to sweep across the landscape and in some other areas, fire was actively suppressed by land managers. The end result was the invasion of hardwood and deciduous trees, changing the makeup of the pine forest and making it unsuitable for indigo snakes.
Gopher tortoises, whose burrows often provide essential shelter for indigo snakes, were having their own problems. Harvested for food, run over by cars, and also suffering from habitat loss and degradation, populations of this stoic reptile crashed throughout their range. When they disappeared, so did the indigo snakes’ favorite hiding spot. Together with collection for the pet trade, habitat loss and road mortality conspired to make the indigo snake increasingly rare, protected in each state where it was known to occur and federally listed as a Threatened species.
Conecuh National Forest in south-central Alabama has been experiencing an ambitious restoration effort for several years. Over time, the landscape has gradually transitioned back to a healthy longleaf pine forest, with numerous clusters of gopher tortoises enjoying the open canopy and abundant sunlight. It wasn’t long before some people started wondering whether it might just make sense to try to bring the indigo snake back to this vast and improved forest. Indigo snakes are important predators, eating rodents, snakes, and frogs. In turn, they provide food for large mammals and raptors. No natural area can be considered whole when it’s missing a species that plays such an important role; Conecuh could never return to its former glory until it again held all the species that once called it home.
Perhaps most importantly, an indigo snake reintroduction would allow generations of Alabamians to experience a thrill that has been denied to them for years. When indigo snakes once again roam through the state, nature enthusiasts hiking through the woods would know they had a chance to come across a giant snake that could reach up to nine feet long! The thought is probably a terrible one for those who suffer from ophidiophobia (i.e. an irrational fear of snakes) but for those of us who appreciate magnificent beasts, the opportunity to spot an indigo snake is terribly exciting. The animals of the southeastern United States are part of our culture, when we lose a species such as the indigo snake, which is found nowhere else in the world, we lose part of our heritage.
All of this was on my mind this morning as I met about thirty other people in an Andalusia parking lot and carpooled to a remote spot in Conecuh National Forest. We whispered to each other and pointed as we spotted two containers, each holding indigo snakes about to be released into the forest. The snakes released today were the offspring of Georgia animals, captured in 2008 and brought into captivity before they laid eggs. After laying, the adults were released back to Georgia although their eggs stayed behind. Held in incubators until they hatched, Auburn researchers monitored the eggs carefully and made sure the proper temperature and humidity levels were maintained. After hatching, the snakes were fattened up on a diet of fish, frogs and lizards to ensure they grew large enough to be inserted with a radio-transmitter. They also received PIT-tags, which are tiny microchips that give each snake a unique identification number. When a PIT tag is detected by a special handheld PIT-tag reader, it will give off a loud beep and the snake’s ID will pop up on the screen.
Releasing snakes back into the wild isn’t as simple as dropping them off and hoping for the best. Some of the animals were to be held in huge pens bordered by hardware cloth fences. The thought is that if snakes are held in these pens for some time, they would be more likely to stay put when the fences were removed and they were free to wander at will. To test whether or not the fences are a benefit, some other snakes were released outside of the pens. By tracking the radio-transmitters inside the snakes, researchers will be able to determine survival rates of the two groups, and whether animals outside of the pens moved greater distances. For a wide-ranging snake like the indigo, frequent movements may expose them to perils such as roads and associated cars.
Anticipation was in the air while the project’s partners, including Auburn University, the U.S. Fish and Wildlife Service, Alabama Department of Natural Resources, Alabama Natural Heritage Program, Zoo Atlanta, and Project Orianne discussed their role in the release. Finally, long-time indigo snake researcher and retired Auburn professor Dan Speake was granted the honor of releasing the first animal. Cameras clicked and flashed as an indigo snake was dropped into a pen and it disappeared into the undergrowth. Just like that, the indigo snake had returned to Conecuh National Forest and the state of Alabama.
One might think that for a reintroduction effort such as this, success has been achieved when the snakes are released and they are crawling through the woods on their own volition. In truth though, it may be many more years before we will know what this huge project has achieved. Having a handful of snakes in Alabama is one thing, but it is essential these snakes eventually form a population capable of reproducing and sustaining itself. As Auburn professor Craig Guyer noted this morning, we won’t know whether all the hard work has paid off until a snake is captured in Conecuh and multiple scans with a PIT-tag reader fail to produce a single beep.
Indigo snake picture courtesy of Kelly Jones
6/18/10 update: The day after the snakes were released, those tasked with tracking the snakes via their radio-transmitters were confronted by a pleasant surprise. The first snake they found was in the process of devouring a copperhead! This gives us all hope these snakes will be able to find their way in the wilds of the Conecuh National Forest.
Posted by David Steen at 8:01 PM