The seemingly endless variations of elevation, exposure, and moisture allow for
an astonishing range of plant and animal communities. The Canyon also acts as a
barrier to many nonflying creatures who live on just one side of the Colorado River
or only in the Inner Gorge. Some mammals evolved into separate subspecies on each
rim. The Abert's squirrel, though common in the Southwest, lives within the park
only on the South Rim. This squirrel has tufted ears and a body and tail that are
mostly gray with white undersides. The shy Kaibab squirrel, easily identified by
an all-white tail and tufted ears, lives only on the North Rim. It probably evolved
from Abert's squirrels that crossed the Colorado River thousands of years ago. Spruce-Fir Forest Ponderosa Pine Forest Pinyon-Juniper Woodland Desert Scrub Riparian Woodlands
Common ravens fly at all elevations in the Canyon and in every season. You may wonder
how they manage under the hot summer sun with their jet-black color, but the
shiny feathers actually
reflect much of the sunlight. The California condor has made a comeback to the Canyon,
thanks to breeding and release programs. You may see them using their nine-foot
wingspan to ride the thermals.
You'll find dense forests of spruce and
fir and groves of quaking aspen on the Kaibab Plateau of the North Rim, mostly above
8,200 feet. Common trees include Engelmann and blue spruce, Douglas fir (not a true
fir), white and subalpine fir, aspen, and mountain ash. Lush meadows, dotted with
wildflowers in summer, spread out in shallow valleys at the higher elevations.
Animals of the spruce-fir forest include mule deer, mountain lion, porcupine, red
and Kaibab squirrels, Uinta chipmunk, long-tailed vole, and northern pocket gopher.
Birds you might see include turkey, great horned owl, saw-whet owl, broad-tailed
hummingbird, hairy woodpecker, hermit thrush, Clark's nutcracker, Steller's jay,
and mountain bluebird.
Stands of tall ponderosas grow between
elevations of 7,000 and 8,000 feet on both rims. Mature forests tend to be open,
allowing in sunlight for Gambel oak, New Mexican locust, mountain mahogany, greenleaf
manzanita, cliffrose, wildflowers, and grasses.
Animals and
birds found here include most of those resident in the spruce-fir forests. The Abert's
squirrel, though common in the Southwest, lives within the park only on the South
Rim. This squirrel has tufted ears and a body and tail that are mostly gray with
white undersides. The shy Kaibab squirrel, easily identified by an all-white tail
and tufted ears, lives only on the North Rim. It probably evolved from Abert's squirrels
that crossed the Colorado River long ago, perhaps during the Pleistocene epoch.
These smaller trees abound in drier
and more exposed places between elevations of 4,000 and 8,000 feet. Their neighbors
commonly include broadleaf yucca, cliffrose, rabbit brush, Mormon tea, sagebrush,
fernbrush, serviceberry, and Apache plume.
Mule deer, mountain
lion, coyote, gray fox, desert cottontail, Stephen's woodrat, pinyon mouse, rock
squirrel, cliff chipmunk, lizards, and snakes (including rattlesnakes) make their
homes here. Birds include mourning dove, plain titmouse, Bewick's wren, black-throated
gray warbler, and pinyon and scrub jays.
Except near permanent water, the low-desert
country below 4,500 feet cannot support trees. Instead, you'll find such hardy plants
as blackbrush, Utah agave, narrowleaf yucca, various cacti, desert thorn, Mormon
tea, four-wing saltbush, and snakeweed.
Animals include bighorn
sheep, black-tailed jackrabbit, spotted skunk, desert woodrat, antelope ground squirrel,
and canyon mouse. Most reptiles hole up during the day, though lizards seem to tolerate
higher temperatures than snakes. Chuckwalla, spiny and collared lizards, common
king snake, whipsnake, and the Grand Canyon rattlesnake live in this part of the
Canyon. The shy Grand Canyon or pink rattlesnake, a subspecies of the western rattlesnake,
lives nowhere else. Birds of the desert scrub have to either look elsewhere for
nesting trees or choose a spot in cliffs or on the ground. Species you might see
include common raven, turkey vulture, golden eagle, red-tailed hawk, rock and canyon
wrens, and black-throated sparrow. You'll probably hear the song of the water-loving
canyon wren without ever seeing him; he sings in an unforgettable descending scale.
Until 1963, seasonal floods of the Colorado
River ripped away most vegetation below the high-water mark. Then, when the Glen
Canyon Dam was completed upstream, tamarisk (an exotic species originally from the
Arabian deserts) speeded up its takeover of formerly barren beaches. Native cattail,
coyote willow, and arrowweed now thrive too. Seeps and springs support luxuriant
plant growth and supply water for desert wildlife.
Beaver,
river otter, ringtail cat, raccoon, deer mouse, spotted sandpiper, blue grosbeak,
Lucy's warbler, Woodhouse's toad, and the tree lizard make their homes near the
streams. Fremont cottonwood trees in the tributaries provide welcome shade for overheated
hikers. The cold, clear waters that flow from Glen Canyon Dam have upset breeding
patterns of the seven native fish species; they now spawn in warmer waters at the
mouths of the Little Colorado River and Havasu Creek. Rainbow trout and 10 other
species have been introduced.