ECOVIEWS: Pine snakes eat rodents, not pine cones
“Do pine snakes eat pine cones?” The answer is no. The name refers not to what they eat but to where most of them live, in sandhill, longleaf pine forests that once covered millions of acres of the Southeast. But someone who does not know that all snakes are carnivorous and none make a living eating plants might think that is why they are called “pine” snakes. People cannot be expected to know the biology of animals unfamiliar to them. And snakes, like other animals, can exhibit peculiar and unexpected behaviors. Efforts are underway to replace longleaf pine habitats in many areas, not just for the return of the pine trees themselves but also to recreate homes for the many other plants and animals that depend on them, including the iconic pine snake.
Pine snakes, the eastern counterpart of western bull and gopher snakes, are a touchstone of a thriving longleaf pine forest. They lay among the largest eggs of North American snakes. When the babies hatch, they are more than a foot in length, longer and heavier than many snake species reach as adults. Most adult pine snakes are 4 to 6 feet long, but some get over 7 feet. They are powerful constrictors, eating mostly small mammals. Rats, squirrels and even rabbits may be on the menu. Pine snakes have pointed noses that serve them in burrowing snout-first into sandy soil. They are one of America’s largest native snakes, but their biology is poorly understood.
Much of what is known about their ecology is the result of rigorous and remarkable field work conducted in the New Jersey pine barrens for more than 40 years by two people – Joanna Burger and Bob Zappalorti. They and their colleagues have discovered previously unknown behaviors of these extraordinary animals. For instance, their large size northern pine snakes lay their eggs underground after digging horizontal tunnels a foot underground and as much as 6 feet long. Other egg-laying females will enter the same burrow and use the same hollowed out chamber, creating a communal nest site. They also dig beneath the soil, sometimes as much as 6 feet deep, to hibernate. What pine snakes do in the southern part of their range remains unknown – an ecological mystery waiting to be solved by some young herpetologist.
Burger and Zappalorti have done a superb job of identifying the conservation threats pine snakes may encounter, a necessary first step in finding ways to help any wildlife species persist in its natural habitat. Simply staying alive in the face of relentless predators that prey on eggs or juveniles is the first hurdle and is part of the natural process. But like so many species of our native wildlife, the additional hazards of living in the modern world can be overwhelming because of human-caused problems. Habitat loss from unchecked development and improper forest management are cited as two problems. Another source of mortality faced by many snakes, especially large, slow-moving ones like pine snakes, is becoming roadkill. One completely unacceptable threat to pine snakes in the study areas where the research is conducted is poaching by collectors who sell snakes. Pine snakes face the same suite of survival risks wherever they occur.
Pine snakes are indicators of a healthy environment, and Burger and Zappalorti are consummate conservationists dedicated to protecting them. Pine snakes are seldom common anywhere these days, so finding one is a good sign that a population has persevered in an area. Perhaps the return of longleaf pine forests combined with more enlightened forest management in sandhill regions of the Southeast will mean the return of more pine snakes as well. With rigorously enforced regulations for habitat protection, pine snakes should do well – as long as they stick to eating rodents, not pine cones, and stop being killed on blacktop roads or illegally poached. Clearly, we humans can play a role in ensuring their continued existence.