Black snake, also known as Western rat snake, is a non-venomous snake species found in central North America.
Adults of black snake can become quite large, with a reported typical total length of 106 – 183 cm. They are the largest snake found in Canada. The body mass of this rat snake can range up to 0.5 – 2 kg in adults.
Juveniles are strongly patterned with brown blotches on a gray background. Darkening occurs rapidly as they grow. Adults are glossy black above with white lips, chin, and throat. Sometimes traces of the “obsolete” juvenile pattern are still discernible in the skin between the scales, especially when stretched after a heavy meal.
This species is a constrictor, meaning it crushes the bones of its prey, coiling around small animals and tightening its grip until they can no longer draw breath, before eating them. Though they will often consume mice, voles and rats, western rat snakes will readily consume any small vertebrate they can catch.
Black snakes are oviparous. The female lays about 12 – 20 eggs. The eggs hatch about 65 to 70 days later in late August to early October. The hatchlings are 28 – 41 cm in total length, and they look like miniature fox snakes.