One of the most unique characteristics of the Grand Canyon is its vast array of terrains. Because of its great length and breadth (over 1,900 square miles), environmental factors have affected the land immensely. Plantlife evolved and adjusted to variations in sun exposure, temperature, and air pressure, depending on where they stood in the canyon's 8,000 feet of elevation. Today, there are approximately 1,737 discovered species of plays, 167 types of fungi, 64 species of moss, and 194 varieties of lichen thriving in the canyon. From dusty desert clay to snowcapped forests, the foliage found within the canyon is as diverse and layered as the canyon walls themselves.
Prominent Plants: coyote willow, catclaw acacia, seep willow, saltcedar, arrowweed, western honey mesquite
The "bottom" layer of the canyon ecology is the riparian community - the plants growing along the bank of the Colorado River. With access to the water from the river and regular sunlight, these plants can grow large enough to shade hikers and river rafters.
Prominent Plants: white bursage, ocotillo, big sagebrush, rubber rabbitbrush, mariola, four-wing saltbush
Beyond the Colorado riverbank and past the riparian foliage the land becomes rocky and dry. Plants that survive here are hardy and need little water - they thrive in the rugged desert conditions.
Prominent Plants: Utah agave, Indian ricegrass, snakeweed, needlegrass, Mormon tea, banana & narrowleaf yucca
The woodlands of the canyon begin at the end of the desert scrub and extend 6,200 feet up the canyon. While this ecological layer of the canyon does not receive much water, the shrubs and small trees here receive a great deal of sun exposure.
Prominent Plants: Ponderosa pine, Engelmann spruce, white fir, blue spruce, mountain ash, Douglas fir
The dense forests of the Grand Canyon emerge at 6,200 feet elevation and continue to the incredible 8,200-foot height of the North Rim. Large trees like these require constant water and can only survive at higher canyon altitudes. Also scattered throughout the forests are wilds grasses that can endure the sub-alpine weather.
Prominent Plants: blue and black grama grass, Indian ricegrass, Aristida grass
These gorgeous grasslands rely on sunlight and plentiful water. At the Grand Canyon, vegetation like this can only thrive in the North Rim.
Of the over 1,700 known plants growing in the Grand Canyon, 12 are endemic - meaning they can be found nowhere else on earth outside of the park's boundaries. Additionally, 63 plants have been designated as "special status" by the U.s. Fish and Wildlife Service. Visitors to the canyon should know that it is not permitted to pick, collect, or remove any form of wildlife from the canyon. Researchers and those working in fields that require plant removal can, however, obtain a permit to do so.
Over the billion years that the Grand Canyon has existed, the face of the North American terrain has changed greatly. The Southwest became increasingly arid and hot, eventually forming 4 deserts: The Mojave, the Sonoran, the Great Basin, and the Chihuahuan. Of these 4, the Grand Canyon cuts through the first 3 of them. As the desert conditions began to take over the land, wildlife in the canyon had to adapt to the temperature in order to survive. This meant depending on alternate food sources, minimizing their need for water, learning to hunt at night when the air was cooler, and finding shelter in the ever-changing forestry. These evolutionary changes took thousands of years, creating the diverse animal kingdom that thrives within the canyon today.
Prominent Mammals: bighorn sheep, bison, elk, coyotes, mountain lions, desert cottontails, raccoons, skunks, squirrels, bats
A great variety of mammals roam the canyon's expanse, from small herbivores like rabbits and squirrels to large animals like elk and bison. Predators like mountain lions and coyotes are a rare sight, as they are quite afraid of humans. Larger animals in general tend to live in less-visited canyon areas, but guests on helicopter tours may catch an aerial glimpse of an elk grazing!
Because the canyon walls are so high - and in some areas, so far apart - many mammals and other creatures exist only on one side or one rim of the canyon. For example, Kaibab squirrels lives only on the North Rim while Abert squirrels (recognizable by their big, fluffy ears) can only be found on the South Rim. Because the South Rim is the most highly toured, Abert squirrels are quite used to humans in their homeland and are typically not at all hesitant to approach guests for a treat - something that is strictly prohibited at the park. Bats are another common sight at the canyon. In fact, there are 22 different species of bat found in the park, both carnivorous (eating insects) and herbivorous.
Prominent Birds: bald eagle, common raven, peregrine falcon, golden eagle, great horned owl, turkey vulture, red-tailed hawk, wild turkey
There are over 200 species of bird seen at the Grand Canyon. Over 60 of them are native to the canyon and have been breeding here for generations. The others are migratory, breeding elsewhere and flying to the canyon seasonally. Due to the ever-evolving canyon foliage, the increased growth in vegetation along the riverbanks (the Riparian area) brought a large amount of birds to nest in the Inner Canyon.
Prominent Reptiles and Invertebrates: rattlesnake, gila monster, collared lizard, short-horned lizard, desert tortoise, black widow spider, bark scorpion
While many people find reptiles and arachnids to be off-putting, these beautiful creatures are a vital component to the Grand Canyon ecosystem. There are actually 17 different species of snake found in the canyon including the pink rattlesnake, which lives nowhere else in the world aside from the Grand Canyon. It is rare that visitors to the canyon will encounter snakes or other reptiles, however, as they live almost exclusively at the bottom of the canyon.
Prominent Fish: humpback chub, speckled dace, razorback sucker, flannelmouth sucker, bluehead sucker
Thousands of years ago there were likely many, many species of fish swimming the Colorado River, but today there are only 5 species native to the waters. There rest were unable to survive the changes in water temperature and the increased speed at which the water began to flow due to erosion. Over the last century, significant efforts have been made to restore and conserve the population of these fish as well as the introduction of a dozen new fish species to the Colorado River.
Fishing in the canyon is permitted for those who obtain a fishing license from the Arizona Game and Fish Department. There are also multiple fishing companies near the canyon that can take fishermen to prime fishing areas like Tapeats Creek and Bright Angel Creek.
Every effort is consistently made to ensure the natural beauty of the canyon remains undisturbed by man. However, the force of nature - specifically flooding - has proven to be the most powerful modifier of the canyon. The combination of the canyon's narrow walls and the regular summer monsoon season cause the Colorado River to regularly flood. In many cases throughout history, the river has flooded to incredibly high levels. For example, in 1921 the Colorado River reached a record flow of 200,000 cubic feet per second, 25 times the river's average flow. Over a 24-year period these rushing waters moved a calculated 4 billion tons of sediment, mud, and sand which slowly but drastically altered the canyon's floor and walls. The power of the flooding also regularly uprooted and washed away the foliage growing along the riverbank.
In order to counteract these effects, the Colorado River Storage Project was developed by the U.S. Bureau of Reclamation. This act depended upon the building of four major water storage units, including the Glen Canyon Dam. After a ten-year construction, the Glen Canyon Dam opened in 1966, about 10 miles from Lee's Ferry. The dam is an integral part of the project as it controls flooding, stores water, generates hydroelectric power to the Southwest, and fills the massive man-made reservoir Lake Powell, a popular recreation area. However, the construction of the dam had unforeseen effects on the Colorado River - and subsequently the plants and animals of the Inner Canyon.
The cold water regularly released from the dam was a shock to the river's native fish, encouraging all 7 species to migrate to warmer waters like Havasu Creek or the Little Colorado River to breed. Major efforts had to be made to reintroduce fish to the area, including several non-native species. Conversely, while the fish population dropped in the Inner Canyon the tamarisk plant population began to grow out of control, covering the riverbanks. The dense branches of this plant cluster in the river to provide a natural dam and flood control but their large growth on land creates a difficult blockade for hikers.
Many of the unexpected effects of the Glen Canyon Dam have proved beneficial to the wildlife. With the flooding under control, algae (an essential food source for many fish) has the opportunity to thrive and grow without being washed away. The abundance of algae has allowed the fish population, as well as insects, butterflies, and moths to grow significantly. Additionally, the perennial plants along the riverbank no longer risk being uprooted by the flood and provide a major food source to dozens of herbivorous animals. Indeed, while the Glen Canyon Dam has played a role in transforming the canyon, it has enabled the plant and animal life in the Inner Canyon to flourish where it otherwise would be wiped out.