National Park Service National Park Service U.S. Department of the Interior U.S. Department of the Interior

Grand Canyon National Park

A Living Canyon: Discovering Life at Grand Canyon

1 rand Canyon's scale and beauty Goverwhelm the senses and inspire awe. At first glance the great chasm appears lifeless, but thousands of interconnected plants and animals bring this magnificent stone wilderness to life.

The canyon's extreme elevation changes and dramatic topography produce a range of climates, creating homes for a surprisingly rich diversity of living things. These organisms' interactions with and adaptations to this rugged environment define Grand Canyon's ecology.

This living canyon is only one part of a larger story. Its forests, deserts, and rivers do not begin or end with Grand Further Information Canyon, just as threats to this ecosystem do not exist only Field Guide to the Grand Canyon by Stephen R. Whitney inside park boundaries. As global climate changes, plants and Field Guide to the Grand Canyon (Pocket Naturalist Series) animals must adapt or they will die. by James Kavanagh nps.gov/grca/learn/nature Whether by foot, bicycle, shuttle bus, or car, Grand Canyon

WATERCOLOR AND SKETCHES © JOHN D. DAWSON provides you with unique opportunities to explore diverse COVER PHOTO: DESERT BIGHORN SHEEP © MIKE BUCHHEIT biological communities and make your own discoveries.

EXPERIENCE YOUR AMERICA™

What Makes Grand Canyon So Special? Living Communities The park's diverse biotic communities provide a range of Life Zones of Grand Canyon What Is the Key to Desert Life? opportunities for many different species of plants and animals to thrive. In fact, Grand Canyon hosts the highest number of Five distinct biotic communities exist in Grand Canyon's In 1889, C. Hart Merriam, head of the Merriam revolutionized the concept of life Water—summer monsoon rain plant species of any national park. How many will you find? ecosystem. Interdependent plants and animals comprise United States Biological Survey, studied zones, which forms the basis of modern and winter snow play a vital Vascular Plants: 1,750 species Exotic (non-native) each unique community. Elevation, light, temperature, Grand Canyon and the San Francisco ecology. He alleged that temperature role in shaping Grand Canyon's Birds: 373 species Animals: 23 species Plants: 198 species slope, aspect, precipitation, and natural disturbances— Peaks, near Flagstaff, Arizona. In 50 short alone dictated life in each zone. Today, we communities. Monsoons form Mammals: 92 species such as fire and flood—contribute to the complexity and miles (80 km) from the summit of the study communities instead of life zones when warm air from the south Endemic (found only in Fish: 18 species (5 native) the park) dynamics of these communities. As you travel through the peaks to the bottom of Grand Canyon, and understand that many more factors rises and cools over northern Reptiles and Amphibians: 57 Animals: 20 species park and beyond, notice how your surroundings gradually Merriam encountered 10,000 feet contribute to each biotic community. How Arizona, creating quickly species Plants: 9 species change. (3,048 m) of elevation change and does Merriam inspire you to investigate moving, violent thunderstorms. Invertebrates: 8,480 known species observed the biological equivalent of Grand Canyon? Conversely, winter storms traveling 1,750 miles (2,816 km) from originate from the north and west, Look for numbers ( , , , etc.) in this brochure. Each species identified with a number is described on the back page. Canada to Mexico. bringing precipitation as snow. Data from Park Profile 2014

Mixed Conifer Forest Located only on the North Rim, this community is the highest and Merriam's Canadian life zone coolest in the park. Life here adapts to an extreme winter climate. See pages 4–5. Summer temperatures: 75°F (24°C)–44°F (7°C) Winter temperatures: 39°F (4°C)–17°F (-8°C) Precipitation: Averages 25 inches (64 cm) per year, including 11 feet (3.5 m) of snow

Ponderosa Pine Forest These forests thrive on the North Rim and South Rim, acting as a Merriam's transition life zone transition zone between the mixed conifer forest and pinyon-juniper See pages 6–7. woodland. Air temperatures are slightly cooler and precipitation is slightly greater than the pinyon-juniper woodland.

Pinyon-Juniper Woodland This mixture of trees flourishes inside the canyon and along the Merriam's upper Sonoran warm, sunny areas of canyon rim. The trees are shorter because this life zone community receives less precipitation than higher elevation forests. See pages 10–11. Summer temperatures: 82°F (28°C)–50°F (10°C) Winter temperatures: 44°F (7°C)–20°F (-7°C) Precipitation: Averages 15 inches (38 cm) per year, including 5 feet (1.5 m) of snow

Desert Scrub Found down inside Grand Canyon, this is the hottest and driest Merriam's lower Sonoran community. Life here adapts to extreme heat and a very dry climate. life zone Summer temperatures: 103°F (39°C)–74°F (23°C) See pages 12–13. Winter temperatures: 58°F (14°C)–32°F (-0°C) Precipitation: Averages 9 inches (23 cm) per year, including 2 inches (5 cm) of snow

Riparian Riparian areas of the inner canyon include springs, seeps, and streams, See pages 14-15. as well as the Colorado River and its banks. Precious water allows for a rich diversity of life, even though air temperatures and precipitation amounts resemble the desert scrub community.

© LISA KEARSLEY Mixed Conifer Forest 3

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An Eventful Life People vs. Predators vs. Prey The high elevations of the North Rim produce a short, As settlers arrived on the North Rim, fears for personal 5 frenzied growing season. Dense, dark spruce and fir forests safety, loss of livestock, and the desire to protect deer and broken by bright, open meadows dominate this landscape. other game animals led to the systematic extermination of 4 In late spring and summer, these meadows will delight you many predators. Hunters killed all the wolves (Canis lupus). with colorful wildflowers and a symphony of bird songs. Mountain lions and bobcats narrowly escaped the same fate. Quaking aspen mix with conifers, often sprouting in areas disturbed by fire. Overhunting, missing predators, and open grasslands meant the deer population exploded and overgrazed native More than Meets the Eye Aspen trees dropping their festive gold leaves signal plants in the forests and meadows. Thousands of deer ate Your trip to the North Rim is winter's approach. The meadows appear stark as plants themselves out of food and starved to death during winter not complete unless you see deer graze in the meadows. become dormant. Some animals busily prepare for winter, 1924–25. This fragile and unique scurrying to store food. Others simply avoid winter through ecosystem comprises only 0.003% of the park. Found hibernation or migration, just as many of you hide inside or Predator populations slowly recover, and we now interspersed with the mixed travel to warmer climates when the snow falls. understand the essential role predators play in maintaining conifer forest, meadows feature amazing diversity, with a healthy balance with their prey. Though wolves have not 15–30 plant species per 0.1 acre In winter, each species must endure or avoid the deep snow returned, park biologists now study a relatively healthy (0.4 ha). Approximately 90% of the grasses, sedges, and other and cold temperatures. Evergreen trees survive with the mountain lion population and how these predators interact plants are native. help of tough, narrow needles packed with chemicals that with their prey, desert bighorn sheep. act like antifreeze. This needle adaptation helps them use While meadows cover only a tiny area, their rich and healthy every warm day for photosynthesis and growth. habitat indicates good air quality—though visibility may be reduced due to air pollution blowing through from other regions. What can you do to reduce air pollution in your daily life to protect Grand Canyon's meadows? An estimated 800 mountain lions, 550 bobcats, 30 wolves, ABOVE PHOTO NPS / TOM BEAN and 5,000 coyotes were killed prior to 1931. TOP BACKGROUND PHOTO NPS / TOM BEAN BACKGROUND PHOTO NPS

4 A Living Canyon: Discovering Life at Grand Canyon Grand Canyon National Park 5 Ponderosa Pine Forest

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An Inviting Openness A Powerful and Creative Process On a warm day near Grandview Point, you may smell the Our Changing Views Forest fire—what comes to mind? While this word may faint aroma of vanilla or butterscotch and see some of the conjure terrifying images for you, the ponderosa pine During the last 100 years, tallest trees on the South Rim. This sweet scent radiates humans altered the forest forest requires this ingredient to survive. Lightning often from the ponderosa pine. These towering pines, with around you by suppressing accompanies summer monsoon storms, bringing the straight trunks, long needles, and orange bark, thrive in wildfires. Before settlement, potential for forest fires. Naturally occurring, low-intensity 9 old-growth ponderosa pine 8 the cooler, wetter areas along the canyon's edge. As you forests featured open, grass- fires clear the forest and add crucial nutrients to the soil. approach Cape Royal on the North Rim, look for this plant covered spaces. Now, you These fires reduce competition, allowing trees to grow tall Do You See the Difference? see thick underbrush and The tassel-eared Abert's squirrel community between the mixed conifer forest and pinyon– dense debris in many places. and healthy. (left) on the South Rim and juniper woodland. Unfortunately, this generates Kaibab squirrel (right) on the hotter, faster fires that have North Rim share a common the potential to consume all With specialized adaptations, ponderosa pine thrives under ancestor. The canyon acts as Ponderosa pines adapt to the region's dry climate with a of the large trees in a forest. natural fire conditions. Deeper root systems provide safety a barrier between the two squirrels. Genetic changes widespread root system and long taproot. Competition for Today, fire managers work to from ground fires. The thick, fire-resistant bark of mature that occurred because of this moisture, nutrients, and sunlight, coupled with frequent safely restore the forest using trees shelter it from all but the most intense forest fires. isolation brought about a distinct fire, creates open forests. Thickets of Gambel's oak grow natural and prescribed fire, coloration in each species. The hazard fuel reduction, and North Rim is the only place in scattered through this plant community, providing an fire effects monitoring. Their the world where the Kaibab important food source and shelter for wildlife. Listen for efforts return balance to the squirrel lives. ecosystem and prepare the ABOVE LEFT PHOTO © US FOREST SERVICE; the Steller's jay scolding from a treetop and perhaps catch forest to face future climate COCONINO NATIONAL FOREST changes. ABOVE RIGHT PHOTO © J.G. HALL a glimpse of wild turkeys (Meleagris gallopavo) strutting TOP BACKGROUND PHOTO NPS / TOM BEAN through the forest.

In 1902 (left), the Matthes Survey encountered a naturally open Hidden Connection ponderosa pine forest. Decades of wildfire suppression resulted Tassel-eared squirrels thrive almost exclusively in ponderosa pine forests, sharing one of Grand Canyon's in a much denser forest (right). closest bonds. The squirrels feed on every part of the ponderosa pine: pollen, cones, seeds, inner bark, and ABOVE (LEFT) PHOTO NPS ABOVE (RIGHT) PHOTO © US FOREST SERVICE, mycorrhizae (a fungus on the roots that helps trees absorb water). Through their scat, the squirrels COCONINO NATIONAL FOREST provide nutrients and spread the helpful fungus which benefits the trees. BACKGROUND PHOTO NPS

11 6 A Living Canyon: Discovering Life at Grand Canyon Grand Canyon National Park 7 Resident Regulars

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17 18 19 6 NPS NPS / MICHAEL QUINN NPS NPS / MICHAEL QUINN Grand Canyon Generalists Do Not Feed Me Back from the Brink While some animals survive in specific Approaching or feeding wildlife is The California condor, largest bird in Today, the greatest threat to condors communities, others thrive nearly prohibited and dangerous. Seemingly tame North America, is a scavenger with a remains poisoning. Unbeknownst to them, anywhere. No matter which Grand Canyon animals are wild and may injure you or a wingspan up to 9.5 feet (2.9 m). Shootings, the birds ingest lead bullet fragments in the community you visit, your best chance to loved one. Many animals carry diseases habitat loss, and lead poisoning almost animal carcasses they feed on outside the see wildlife is to walk quietly and look for that can be transmitted to humans. Animals caused their extinction. In 1996, biologists park. Land managers promote using non– one of these resourceful creatures: raven, develop a dependency on human food and reintroduced condors to Arizona and now, lead ammunition, which helps preserve and rock squirrel, deer, coyote, or elk. are more likely to die younger. For your some condors use remote caves in Grand expand the current endangered condor safety—and the animals'—view wildlife Canyon as nest sites. population. from a safe distance of 75 feet (23 m).

8 A Living Canyon: Discovering Life at Grand Canyon Grand Canyon National Park 9 Pinyon-Juniper Woodland

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Life in Dry Woodlands You Can Save a Life Hot, dry breezes rise from inside the canyon. Thin soils Invasive Elk The seemingly bare ground between large plants is rarely close to the canyon's edge hold little water, and trees unoccupied. Extremely sensitive biological soil crust takes grow short, gnarled, and twisted. Trees conserve precious decades to form. These crusts play important roles in

20 water with waxy coatings on their needles or scale-like reducing soil erosion and increasing water conservation. leaves. Though it does not appear lush, the pinyon-juniper You can prevent damage to delicate vegetation by walking Bluebird Feast In early winter, bluebirds relish woodland houses fascinating relationships. on established trails. 27 the small, succulent pink berries of juniper mistletoe. Mistletoe is a partial parasite, dependent Animals bring life to this community. Pinyon jays co- On the South Rim, off–trail on its host tree for water and evolved with pinyon pines: they eat and spread massive foot traffic nearly trampled one minerals, but feeds itself by 24 photosynthesis in its yellowish- amounts of pine nuts—not a true nut, but a seed—storing miniature, ground-hugging green stems. them in soil miles away to return to and eat later. Every few Viewing the large elk herds in member of the pea family out ABOVE PHOTO NPS years, when the pinyons put out a bumper crop of pine the park is exciting. However, of existence. Today, fencing TOP BACKGROUND PHOTO © NPS / TOM BEAN park managers consider nuts, the jays cache far more than they need for food, giving non-native species, like elk, protects the endangered sentry birth to a new generation of trees. invasive to Grand Canyon. milk-vetch, a plant that only In the early 1900s, humans introduced Rocky Mountain grows along the canyon's edge American robins (Turdus migratorius), bluebirds, coyotes, elk into Arizona. Elk migrated in narrow bands atop the porous north from the Williams area Kaibab Formation. and gray foxes all depend on the berries—or modified and eventually made a home cones—of the Utah juniper for a year-round food source. at Grand Canyon. They survive You may see the beginnings of a new juniper with a bit of here quenching their thirst Park botanists are experts at on unnatural water sources organic fertilizer attached. Look for these large tan seeds or and feasting on non-native growing and replanting this blue berries in orange-brown coyote scat. grass. What role can you play fragile plant where careless to manage non-native species where you live? footsteps almost eliminated it. ABOVE PHOTO NPS / MICHAEL QUINN Your actions to stay on trails can TOP RIGHT PHOTO NPS / MICHAEL QUINN 23 MIDDLE RIGHT PHOTO NPS / MICHAEL QUINN protect this community, BOTTOM RIGHT PHOTO NPS including its endangered and endemic species.

10 A Living Canyon: Discovering Life at Grand Canyon Grand Canyon National Park 11 Desert Scrub

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Adaptations to Desert Life Climate Chroniclers If you hike down into Grand Canyon, with every step you Windows to the Past Ancient hoarders provide a glimpse into will quickly discover it gets hotter and dryer. Elevation Grand Canyon's past. Packrat (Neotoma spp.) urine and temperatures at Phantom Ranch, at the bottom of the solidifies middens containing evidence of seeds, leaves, canyon, equate to those found in Phoenix, Arizona. Here, and bones collected nearby. Middens can survive more limited precipitation comes as cold, gentle winter rain and than 30,000 years in this dry climate, providing wonderful violent summer monsoon thunderstorms. snapshots of past environments.

28 The Sonoran, Mohave, and Great Basin deserts meet in Middens, along with giant ground sloth (Order Pilosa) Hiking Down into Grand Grand Canyon, sustaining a rich diversity of life. Following dung, condor bones, and pollen preserved in caves, Canyon in Spring? a wet winter, spring wildflowers will delight and amaze illustrate stable, colder temperatures 11,700 years ago. Some Keep your eyes out for 12-foot you. The beautiful descending whistle of the canyon wren What will packrats find plant species, such as the limber pine (Pinus flexilis), have (3.7 m) tall flowering yellow at Grand Canyon in the stalks. While some plants bloom (Catherpes mexicanus) adds a memorable soundtrack to centuries to come? Our own since disappeared from Grand Canyon. Other species, like annually, the century plant your hike. daily actions influence global juniper, are now only found at higher elevations. blooms only once after 15–25 climate, which in turn affects years and then dies. Ancestral the plants that grow here Puebloan people and the Nocturnal animals, such as ringtails, owls (Order and the animals that depend Although climates always change, human activities Havasupai Tribe made baskets on them. Will future packrat and hair brushes from this Strigiformes), and bats (Order Chiroptera), avoid the middens contain the same currently accelerate this process. Park managers implement plant's fibers. scorching heat by resting during the day and emerging from seeds and bones they do sustainable practices that decrease greenhouse gas ABOVE PHOTO © JO SUOMALA today? TOP BACKGROUND PHOTO NPS / TOM BEAN shelters at night. This useful adaptation helps them survive emissions, conserve water, increase recycling, and use ABOVE PHOTO OF MIDDEN © NANCY E. the extreme heat. Take a hint from these animals and avoid MULEADY-MECHAM alternative energy and fuels. What daily practices do you hiking in mid–day heat. 31 use to protect your planet?

Riparian Oases in the Desert Springs and seeps make up just 0.01% of Grand columbine (Aquilegia flavescens), and crimson Some, such as Roaring Springs below the North Park scientists study the springs, seeps, and Canyon's landscape, but species concentrations monkey flower Mimulus( cardinalis). Each unique Rim, provide drinking water for visitors. Proposed streams, as well as the hydrology of the may be 500 times that of the surrounding desert. water source provides a home to plants or insects, mining claims and new developments near the surrounding plateaus, applying the best science Essential to life, these enchanting places showcase some of which are found nowhere else on Earth. park threaten springs by drawing water from to protect this life-giving resource. How can you delicate maidenhair fern (Adiantum sp.), yellow aquifers extending beyond park boundaries. reduce your water use where you live?

12 A Living Canyon: Discovering Life at Grand Canyon Grand Canyon National Park 13 Riparian Effects of Glen Canyon Dam on the Colorado River Characteristic Pre-Glen Canyon Dam Post-Glen Canyon Dam Water Color Reddish-brown, sediment-laden. Cold and clear except when tributaries contribute sediment.

Water Temperature 33–40ºF (0.5–4.4ºC) winter. Near 48ºF (9ºC) year-round. Warms 75–85ºF (24–29ºC) summer. slightly during summer and downstream. Sandbars/Beaches Plentiful. Renewed by annual Dramatic decrease in size and number. flooding. Vegetation Scoured from beaches during annual Increased growth to water's edge. flooding. Little plant life growing in Dominated by tamarisk. Single-celled river due to sediment load. diatoms and algae growing in river. Human Activity Limited. Unregulated. Very popular for rafting. Strictly regulated. 35 Floods Seasonal. Scoured debris and rebuilt Controlled or human-made. Much beaches. Scoured vegetation from smaller scale and duration. river edge. 36 Glen Canyon Free-flowing river through natural, Full of water and sediment. Overcoming Obstacles wild canyon. Provided wildlife habitat Created Lake Powell and its recreational The Colorado River originates in Colorado's Rocky and scenic beauty. activities. Mountains and flows over 1,400 miles (2,253 km) to the Gulf of California. As it runs 277 miles (446 km) through Grand Canyon, it loses 2,000 feet (610 m) of elevation, Why Do Tributaries Matter? At Grand Canyon, 768 year-round averages 300 feet (91 m) wide, and 40 feet (12 m) deep. and intermittent streams and The river, together with its tributaries, seeps, and springs, rivers flow into the Colorado River. The canyon's intricate comprises the riparian community of Grand Canyon. rand Canyon's dynamic ecosystem system of tributaries survived the construction of Glen Canyon Dam, provides a sanctuary for an incredible Construction of Glen Canyon Dam in 1963 brought about G and today National Park Service diversity of life. While the biological communities biologists use these protected a series of changes to the river and its ecosystem. However, places to manage native fish the powerful waterway still exists as a safe haven for several inside the canyon may be different from those on species. native species of fish, including the endangered humpback the rim, relationships between living things and Using a method called tributary chub (Gila cypha), speckled dace (Rhinichthys osculus), translocation, biologists their adaptations to the environment connect all transport populations of native flannelmouth sucker Catostomus( latipinnis), bluehead fish to tributary environments sucker (Catostonus discobolus), and razorback sucker parts of this remarkable place. downstream in western Grand Canyon. Warmer water (Xyrauchen texanus). Endangered razorback sucker were temperatures and fewer even discovered spawning here in 2014 for the first time The qualities that make Grand Canyon an important refuge nonnative predators provide the for plants and animals also make it an important retreat ideal conditions the fish need to in decades. Active management of these native fishes by reproduce. National Park Service biologists enables the Colorado River for humans in a time when access to nature is increasingly ABOVE PHOTO NPS to continue to be a significant regional refuge for these limited. It is truly a place of exploration, wonder, and TOP BACKGROUND PHOTO NPS / NIC K. BEREZENKO unique species. discovery for you to enjoy and protect. 34 Tread carefully. Your actions impact every community you visit because everything is connected. Whether at Grand A Complex Condition Canyon National Park or in your own neighborhood, you Since the Glen Canyon Dam introduced a steadier flow regime and eliminated spring floods, tamarisk (Tamarix spp.)—an invasive shrub—dominates beaches throughout Grand Canyon. However, tamarisk have the power to positively influence your surroundings attracts insects, providing food for birds and animals. In fact, Bell's vireo (Vireo bellii), a bird in decline and help protect natural places for future generations. across its range, extended its range more than 100 miles (161 km) upriver because of the food provided in these new nesting sites.

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