The Grand Canyon rattlesnake (C. oreganus abyssus) is a subspecies of the more broadly spread Western rattlesnake (Crotalus oreganus). Blending into Grand Canyon's varied rock layers, this venomous pit viper uses its rattle to warn predators off, the tiny muscles firing up to fifty times per second--some of the fastest known to science. Take a "Minute Out In It" to appreciate the power of a zoom lens, since our ranger knew to keep a very safe distance from the hemotoxic venom of this coiled carnivore.
Rattlesnakes
Nine species of rattlesnake are found in the general vicinity of Grand Canyon (one of which, the Western Rattlesnake, is represented by two subspecies in the park).
Five species are found within the boundaries of Grand Canyon National Park (Western Rattlesnake [Grand Canyon and Great Basin subspecies], Speckled Rattlesnake, Black-tailed Rattlesnake, and Prairie Rattlesnake), and four have been documented below the rim inside the Grand Canyon (Western Rattlesnake [Grand Canyon subspecies], Speckled Rattlesnake, Black-tailed Rattlesnake, and Western Diamond-backed Rattlesnake
Rattlesnakes fill important ecological roles as both predators and prey. Rattlesnakes are generally harmless when left alone but will strike in self-defense. When threatened, these snakes usually try to escape or hide before biting. Please observe these venomous predators from a distance.
Identification
The rattlesnake’s most prominent physical feature is the rattle on the end of its tail. The rattle is made of interlocking segments of keratin (the same material found in human hair and fingernails). When threatened, the snake’s rattle creates a buzzing noise that warns off potential predators. By scaring away predators without a fight, rattlesnakes avoid injury and conserve their venom needed for hunting.
Rattlesnakes have a thick, broad body and a distinctive diamond-shaped head, although this is also true of some of our non-venomous snakes.
Rattlesnakes are pit vipers. Pit vipers are venomous snakes that have heat-sensing pits on the sides of their face that help them detect prey.
Rattlesnakes documented in Grand Canyon National Park
Grand Canyon Rattlesnake
Crotalus oreganus abyssus
Often described as pink in color, this species is found nowhere in the world but the Grand Canyon. Commonly observed from Lees Ferry to the vicinity of National Canyon, primarily below the rim.
Great Basin Rattlesnake
Crotalus oreganus lutosus
Commonly observed on the north rim from the House Rock Valley region to Tuweep above the rim on the north side of the Canyon. Occasionally observed between the rim and the top of the redwall limestone in this same region.
Black-Tailed Rattlesnake
Crotalus molossus
Occasionally observed from the vicinity of Havasu Canyon to Pearce Ferry above and below the rim.
Prairie Rattlesnake
Crotalus viridis
Locally common above the rim from the Echo Cliffs region to the region above Havasu Canyon. This snake has not been documented below the rim.
Speckled Rattlesnake
Crotalus pyrrhus
Commonly observed in the western part of the park from the vicinity of Havasu Canyon to Pearce Ferry below the rim.
Other Rattlesnakes
Documented in the Grand Canyon Region, but not confirmed in Grand Canyon National Park
Arizona Black Rattlesnake (Crotalus cerberus) Infrequently observed above the rim on the south side of the canyon west of Havasu Canyon.
Western Rattlesnake (Crotalus oreganus) Midget Faded Rattlesnake (Crotalus oreganus concolor) A subspecies of the Western Rattlesnake. Common near parts of Lake Powell.
Western Diamond-backed Rattlesnake (Crotalus atrox) Common in the vicinity of Lake Mead, but rarely observed below the rim. Documented solely from Peach Springs Canyon below the rim.
Sidewinder (Crotalus cerastes) In our area, this species has been infrequently observed in Grand Wash, which is near (but not part of) Grand Canyon.
Mohave Rattlesnake (Crotalus scutulatus) Relatively common near Pearce Ferry and documented above the rim in the vicinity of Quartermaster Point, this species has not yet been documented in (below the rim of) Grand Canyon.
Habitat
While they are occasionally found on the rim, rattlesnakes are primarily observed within the canyon.
Most rattlesnakes in Grand Canyon are observed adjacent to springs, streams, and the river.
Rattlesnakes have adapted to a wide variety of habitats and occur throughout much of the continental US.
Rock crevices, burrows, and leaf litter make for excellent cover from predators and hiding spots to ambush prey.
Behavior
Rattlesnakes are ambush predators; they wait motionless until their prey (small mammals, birds, and other reptiles) move close enough to strike.
During the winter, rattlesnakes enter a state called brumation. Similar to hibernation in mammals, when a reptile brumates it becomes lethargic and slow, sometimes not moving at all for the duration of cold weather.
Because rattlesnakes are ectotherms (meaning they do not regulate their body temperature metabolically like mammals do), they are often observed basking in the sun to warm themselves during cooler weather.
Fun Facts
According to the Arizona Poison and Drug Information Center, less than 1% of rattlesnake bites result in human deaths.
Rattlesnakes are ovoviviparous, which means the egg sacs are incubated within the mother so that the young emerge fully developed. This essentially means that rattlesnakes give birth to live young.
Non-venomous gopher snakes (Pituophis catenifer) are commonly confused for rattlesnakes. They have a series of black bands on their tails that mimic the rattle found on rattlesnakes. When threatened, a gopher snake will rapidly vibrate its tail, confusing an attacker into thinking it’s a venomous rattlesnake.
Page Contributors: Andy Holycross, Brandon Holton, Tessa Corsetti, and Trevor Persons