The term “black snake” in North America often refers to one of two distinct species: the Eastern Rat Snake (Pantherophis obsoletus) and the Eastern Racer (Coluber constrictor). Both are non-venomous and share the uniform dark coloration that leads to the common name. Their feeding habits, however, contrast sharply between the powerful, climbing predator and the quick, ground-level pursuer.
The Constrictor’s Menu
The Eastern Rat Snake is a powerful, heavy-bodied predator that primarily targets warm-blooded animals, reflecting its role as a natural rodent controller. Its diet centers on small mammals, including mice, rats, voles, and chipmunks, which it consumes whole after subduing them. Adult Rat Snakes are large, reaching lengths of up to seven feet, which allows them to take on substantial prey, including small rabbits, squirrels, and juvenile opossums.
This species is also highly arboreal, using its keeled scales to ascend trees and structures in search of food. Once aloft, the Rat Snake frequently raids bird nests, consuming both nestlings and eggs. Juveniles, however, often rely on a higher proportion of cold-blooded prey, such as frogs and lizards, before transitioning to the predominantly mammal-based diet of their adult years.
The Racer’s Rapid Diet
In contrast to the Rat Snake’s focus on warm-blooded prey, the Eastern Racer is a more opportunistic carnivore with a broader menu of smaller, quicker targets. Racers are known for their speed and agility, which they use to capture a diverse range of amphibians, reptiles, and invertebrates. Their diet includes small frogs, lizards, and even other snakes, demonstrating a tendency toward consuming quick-moving, cold-blooded animals.
Young Racers rely heavily on insects and other soft-bodied invertebrates like spiders and crickets. While adults do consume rodents, they typically target smaller individuals like shrews and young mice, as opposed to the larger rats and squirrels favored by the Rat Snake. This specialization on a variety of smaller prey allows the Racer to thrive in open habitats like prairies and fields.
Hunting Strategies and Prey Capture
The two species employ fundamentally different mechanisms to acquire and incapacitate their meals. The Eastern Rat Snake is a classic constrictor, subduing prey by wrapping its body tightly around the animal. Research indicates this pressure overwhelms the prey’s circulatory system, leading to rapid unconsciousness and death from ischemia, rather than suffocation.
Rat Snakes hunt using both active foraging and ambush tactics, relying heavily on chemosensory cues detected by their forked tongue and Jacobson’s organ to track down rodents. The Eastern Racer, despite its Latin species name constrictor, does not truly constrict its prey. It is a highly visual, active hunter that pursues its quarry, often raising its head to survey its surroundings in a behavior known as “periscoping.” Smaller prey is frequently overtaken with a quick strike and swallowed alive, while larger items may be pinned to the ground with a loop of the body or chewed until they expire before being consumed.