Yellowstone National Park
Social Studies Explorer
An Expedition into the Geography, History and Economy of
The World’s First National Park
“For the benefit and
the enjoyment of the
Established in 1872, Yellowstone National Park
is the World’s First National Park. It an is a
wild wonderland of fire and ice. Yellowstone is
home to over half of the world’s thermal
features, including Old Faithful.
Yellowstone is a place of extreme beauty,
solitude and chaos. The Yellowstone Caldera
remains one of the most powerful geologic and
volcanic systems in the world. Paradoxically
the Great Yellowstone Ecosystem fuels a
complex diversity of life. The Yellowstone
River, which originates in the park is the largest
undammed river in the country and is one of
the last pristine water systems in the U.S.
So grab your binoculars and prepare as we go
on a Social Studies tour of Yellowstone, learning
about the park’s geography, history, culture and
A land of fire and ice
What is Geography: the study of the physical features of the earth and its
atmosphere, and of human activity as it affects and is affected by these,
including the distribution of populations and resources, land use, and
• Four spheres: the atmosphere, biosphere, hydrosphere and lithosphere
• The biosphere is the global sum of all ecosystems. It can also be termed
the zone of life on earth. It is largely self-regulating (troposphere,
hydrosphere, lithosphere (rocky crust))
• Hydrosphere is composed of all the water on or near the earth. This
includes the oceans, rivers, lakes and even the moisture in the air. Ninety-
seven percent of earth’s water is in the oceans. The remaining three
percent is fresh water, three quarters of the fresh water is solid and exists
in ice sheets
• Yellowstone National Park is located deep in the wild backcountry of
Montana, Wyoming and Idaho in the Northern Rockies. Yellowstone
land of fire and ice; a wonderland of chaos and conflict peace and
solitude. It is a land of extremes from frigid winters to sublime
summers, tranquil alpine lakes and thundering geysers and boiling hot
• Yellowstone is one of the earth’s most geographically diverse and
dynamic bionetworks. The park is located atop the Yellowstone
Plateau and Yellowstone Caldera. The park is crisscrossed by the
backbone of the Continental Divide. Yellowstone is home to
mountains, valleys and alpine habitats. The park has dozens of
microclimates depending on varying factors of volcanic, geographic
and geological forces.
• Yellowstone’s geography is complex, unique and interconnected. The
geography of this land of fire and ice is the crux of flora, fauna and
human interactions within the park.
Yellowstone Geography Quick Facts
- 96% of the land area in Yellowstone is
located within the state of Wyoming.
Another 3% is within Montana, with the
remaining one percent in Idaho.
- Yellowstone is an active supervolcano.
- The park is 63 miles north to south and
54 miles west to east by air.
- Yellowstone National Park spans 2.2
million acres. In area it is larger than the
states of Rhode Island or Delaware.
Yellowstone is the second largest national
park in the continental U.S. after Death
Valley NP in CA
- Yellowstone’s geography is a diverse
confluence of open forests, rivers and
lakes, thermal areas, mountains, canyons
- Yellowstone lies on the 45th Parallel
- 5 park entrances: Gardiner MT, West
Yellowstone MT, Cooke City (Northeast) MT,
Eastern Entrance (70 miles west of Cody WY)
and the southern entrance from the Tetons
Quick Facts Continued
- YNP is a designated World Heritage Site and
designated Biosphere Reserve
- Highest Point: 11,358 feet (Eagle Peak
- Lowest Point: 5,282
- Approximately 5% of park is covered by
water; 15% is grassland; and 80% is forest
- Precipitation ranges from 10 inches at the
north boundary to 80 inches in the
- Temperatures at Mammoth Hot Springs
(north entrance to park): January: 9 degrees,
July: 80 degrees
- The park is home to over 67 species of
- 3 million people a year visit Yellowstone
from around the world!
- Yellowstone has over 1000 miles of
backcountry trailheads that trek into the
diverse topography, allowing visitors to tour
the geography of the park on foot.
• Famous mountain explorer John Bridger called Yellowstone, ‘the place hell
bubbled up.’ Yellowstone is one of the world’s most active volcanoes.
Lewis and Clark Explorer John Colter is the first white man who glimpsed
into Yellowstone’s wonders– the stories of lakes of fire and sulfur steam
were so astounding people laughed Colter off as a maniac. They
nicknamed the land of Yellowstone as ‘Colter’s Hell.’
• Yellowstone’s geothermal activity is fueled by a subterranean hotspot
where light, hot molten rock from the mantle rises towards the surface. A
series of eruptions 2.1 million, 1.3 million and 640,000 years ago create the
majority of geologic and geographic features within the park today. The
final eruption caused the Yellowstone Volcano to collapse forming a 30 by
45 mile caldera. The caldera rim is visible around the park, including Fairy
Falls in the Lower Geyser Basin region.
• Yellowstone is home to over 10,000 thermal features – over 2/3 of the world’s
geothermal activity. Thermal features are concentrated mostly within the
boundary of the 30 by 45 mile caldera rim. Geothermal activity is divided into
• Thermal features within the park include: Geysers, Hot Springs and Fumaroles
• A fumarole, also called a steam vent, occurs when a hydrothermal has so little water in
its system that the water boils away before reaching the surface. Steam and other gases
emerge from the feature's vent, sometimes hissing or whistling. Steam vents are often
superheated, with temperatures as high as 238°F
• A GEYSER is a hot spring that erupts periodically and forcibly ejects water. Three
ingredients are necessary for a geyser to exist: a source of heat, an abundant
supply of water, and a special underground plumbing system. Yellowstone is
home to over 500 geysers, more than any in the world; including the world’s most
powerful geysers Steamboat (Norris Basin), most powerful predictable geyser:
Grand Geyser (Upper Basin) and most famous geyser in the park: Old Faithful
Hot Springs are the most common hydrothermal features in Yellowstone. Beginning as precipitation,
the water of a hot spring seeps through the bedrock underlying Yellowstone and becomes
superheated at depth. An open plumbing system allows the hot water to rise back to the surface
unimpeded. Convection currents constantly circulate the water, preventing it from getting hot
enough to trigger an eruption.
Yellowstone Thermal Features: Life at the
• Hot Springs Colors Many of the bright colors found in Yellowstone's
hydrothermal basins come from "thermophiles" —microorganisms that
thrive in hot temperatures. So many individual microorganisms are
grouped together—trillions!—that they appear as masses of color.
• Different types of thermophiles live at different temperatures within a hot
spring and cannot tolerate much cooler or warmer conditions.
Yellowstone's hot water systems often show distinct gradations of living,
vibrant colors where the temperature limit of one group of microbes is
reached, only to be replaced by a different set of thermophiles.
• Grand Prismatic Spring is home to millions of living bacteria and is a
dynamic ecosystem. Many microbiologists study thermophiles and their
ability of adaptation, including cancer research and alternative energy
Yellowstone’s Geothermal Features demonstrate the interconnectedness of our earth’s geology,
geography and social sciences. The geologic forces mold the geography, while the geography affects
the biodiversity and human interaction with the land. The economy of Yellowstone is linked strongly
to the tourism of the park’s thermal features including Old Faithful.
Old Faithful is the most famous geyser in
the world. It erupts on average every 90
Grand Prismatic Hot Spring is the
world’s second largest hot spring.
- 80% of Yellowstone National Park is
covered in forest and the greater
Yellowstone ecosystem (stretching from
WY to ID to MT) is home to twenty-seven
national forests including the Bridger-
Teton, Gallatin, Shoshone, Custer and
- Forests in Yellowstone are complex
habitats serving as the lifeblood of the
park. The forest ecosystem provides
homes for the smallest of park wildlife
such as birds and squirrels to Grizzly and
Black Bears, Elk, Moose and more. The
forest ecosystem is home to hundreds of
plant species as well as bugs,
microorganisms +++ the forest is
interconnected in a circle of life
• The Park is home to seven species of conifer:
- Lodgepole Pine
- White bark Pine
- Engelmann Spruce
- Subalpine fir
- Rocky Mountain Juniper
- Limber pine
- The park is also home to some deciduous species, including:
- Quaking Aspen and Cottonwood
Yellowstone’s forest ecosystem is driven by
intervals of fire. Fire is a force of destruction.
In 1988 over half of Yellowstone’s forest were
consumed by flames. Forestry experts
assumed Yellowstone’s vibrant forest
ecosystems were lost or marred for
centuries. What they learned is
extraordinary, the forest naturally reseeded
itself. Species such as Lodgepole Pine and
Quaking Aspen only reseed during period of
extreme heat. Quaking Aspen’s root system
is so deep that it begins to regrow from its
roots even if its entire forest structure is
burned to ash. Yellowstone’s forests are
thriving again. Foresters understand that fire
is a force of rebirth in the park, allowing the
forest to stay healthy – preventing
overcrowding of trees, freeing up space for
more habitat and allowing for a flourishing
diverse ecosystem. The balance of fire and
life is a delicate one in Yellowstone Park.
Forest Fires act as a force of destruction
Yellowstone’s Lakes and Rivers: Yellowstone is
a diverse hydrosphere.
• Yellowstone’s lakes, rivers, and water systems fuel the greater
Yellowstone Ecosystem, nourishing the land, flora and fauna.
Yellowstone Lake is the largest body of water
in Yellowstone National Park, spanning 136
square miles and 110 miles of shoreline. At an
altitude of 7,732 feet , it is the largest high
elevation (above 7,000 feet) lake in North
Yellowstone Lake is home to the native
cutthroat trout. Unfortunately the indigenous
Cutthroat is being threatened by the invasive
non-native Lake trout. Efforts to save the
cutthroat trout include scientific studies into
spawning grounds and protections, angling
(lake trout are caught to remove them from
Fishing Bridge used to be a popular spot for
fishing, as it lies at the spawning ground of
Cutthroat. Over fishing depleted the
population. Fishing at Fishing Bridge is now
outlawed but it is still a wonderful spot to
catch a stunning view of Yellowstone Lake.
• Yellowstone has countless backcountry lakes from the tiniest – Isa
Lake, with straddles the Continental Divide, to Heart Lake, and
Shoshone Lake, the largest backcountry lake in the lower 48.
• Both Heart Lake and Shoshone Lakes are home to isolated thermal
features. The hike to Shoshone Geyser Basin is nearly twenty miles
roundtrip on foot. Heart Lake Basin can been accessed in a moderate
11 mile RT hike.
• Isa Lake is so small it resembles a pond. In truth ‘it is a lake’ that
straddles the Continental Divide. Its waters flow to Atlantic and
Pacific! Isa is know for its beautiful water lilies in the summer
months. (see photo below)
The Yellowstone River
- The Yellowstone River is the longest
free-flowing river in the continental
United States. It traverses over 600
miles of rugged and pristine
wilderness from Yellowstone Lake to
The Grand Canyon of the
Yellowstone, Tower Falls and more.
- The Yellowstone River is a tributary
of the Missouri River. The
Yellowstone is vital to providing
moisture from Wyoming to North
- The Yellowstone River has played a
role in forming the landscape of the
park, cutting away at canyons
including the spectacular Grand
Canyon of the Yellowstone.
Each river is vital to the Yellowstone
Ecosystem. Each river has its own
personality and beauty. You can explore
Yellowstone Rivers through backcountry
hiking trails, white water rafting and angling
Yellowstone is a angler’s paradise. Just
remember: ‘Catch and release.’
Yellowstone is a Wonderland of Waterfalls
The Lower Falls of the Yellowstone Tower Falls of the Yellowstone
• Yellowstone’s mountains are part of the Rocky Mountain front.
• There are at least 70 named mountain peaks over 8,000 feet in Yellowstone
in four mountain ranges.
• The Washburn Range and the Red Mountains are completely enclosed in
the boundaries of the park.
• The Gallatin Range begins approximately 75 miles north of YNP near
Bozeman and dominates the northwest corner of the park.
• The Absaroka Range, the largest range in the park, begins approximately 80
miles north of the park near Livingston Montana and runs southeast into,
then south through the entire eastern side of the park to the Wind River
Range in Wyoming.
• Yellowstone is a land of canyons, each opening a window into the
geologic forces of nature that created the spectacular gorges, as well
as the geography of the land. Canyons in Yellowstone were carved by
erosion, volcanism and glaciation
• Yellowstone has dozens of canyons, each with a unique history and
striking appearance. The most famous of the park’s canyons is the
Grand Canyon of the Yellowstone. Other major canyons include: The
Black Canyon of the Yellowstone, Lewis Canyon and the Golden Gate
Grand Canyon of the Yellowstone
• Formed by volcanism, glaciation, uplift, erosion and the power of the Yellowstone
River, The Grand Canyon of the Yellowstone is a symphony of nature’s art in
motion. It is an awe-inspiring beauty of depth, drama and color.
• The Canyon is twenty-four miles long and between 800 and 1,200 feet deep. It
has a width ranging from .25 to .75 miles across.
• The canyon serves as a habitat for the park’s osprey and eagle populations.
Grizzlies, elk and other mammals live on the precipice of the canyon rim in
• The canyon’s palette of yellows and pinks are stunning, but the canyon’s claim to
fame is its breath taking waterfalls.
• The Upper Falls of the Yellowstone tumble 109 feet from the canyon wall. The
brink of the upper falls marks the junction between a hard rhyolite lava flow and
weaker glassy lava that has been more easily eroded and helps form the splendor
of the canyon’s color.
The Lower Falls of the Yellowstone
• The Yellowstone River crashes majestically 308 feet over 590,000 year
old Canyon Rhyolite lava flow into the depths of the canyon.
• It is the largest volume waterfall in the Rocky Mountains gushing on
8,4000 cubic feet/s at peak runoff
• The color, light and sheer drama of the falls inspired painter Thomas
Moran who accompanied the Hayden Expedition on 1871 on the first
official government sanctioned exploration of the park. His painting
of the Lower Falls from the Canyon’s Artist Point convinced Congress
to create Yellowstone as the world’s first national park on March 1
The Lower Falls in Color
Thomas Moran’s painting from Artist Point Millions of tourist’s each year take a snapshot of this
grand view of the Lower Falls
Valley: an extended depression in the Earth’s surface that is usually bounded by hills or mountains
and normally occupied by a river or stream. Valleys are the most common geographical formation
on the Earth. Yellowstone’s Valleys are formed by a mix of erosion, glaciation, volcanism and uplift.
• Yellowstone is home to a wide array of valleys from hidden leas deep in the backcountry
to wide open tracts of vast pristine open spaces. Yellowstone’s Valleys act as arteries to
the park’s overall health, providing habitat for the park’s flora and fauna. Valleys are
micro-ecosystems within the greater ecological structure and biosphere. Yellowstone’s
valleys act as agents of a confluence – transitioning points from mountains to canyons to
prairies…as agents of transition they are gathering points for wildlife, geographic and
geologic forces and history! A few of the major valleys in Yellowstone include:
• Hayden Valley: Located in the heart of Yellowstone located to the west of Yellowstone
Lake, east of The Grand Canyon of YNP…
• Lamar Valley: Located in the Northeastern corner of the park, isolated by the Beartooth
and Absaroka Mountains and Gallatin Ranges. This is one of the most important areas for
wildlife in the park
• Gibbon Valley: Located amid geysers and hot springs, the Gibbon Valley is a popular spot
Hayden Valley-The Heart of Yellowstone’s Wild Side
- Located in the heart of the Yellowstone Plateau, the
valley is a confluence of geography, geology, history
and wilderness exploration. It also is home to a few
thermal features including the Mud Volcano basin
- The Hayden Valley is the largest valley in Yellowstone.
- Hayden Valley lies 8,000 feet above sea level and is
surrounded by 12,000 foot mountains. The
Yellowstone River ambles peacefully through the
valley before making its way to its chaotic descent
into the Grand Canyon of the Yellowstone.
- The Hayden Valley is an old lake bed. During the
Pinedale glaciation, which ended 14,000 years ago,
water from Yellowstone Lake flooded the 17,000 acre
valley. Eventually the waters receded exposing the
lake bed as a fertile valley with nutrient rich soil to
support a diverse mix of wildlife.
- Wildlife in Hayden Valley includes:
- Bison: in August the largest free roaming bison rut in
the world occurs in the valley
- Grizzly and Black Bears
- And hundreds of birds including Yellowstone’s
Trumpeter Swan and Pelicans
Located in the northeastern corner of Yellowstone,
The Lamar Valley is an untouched wilderness
marked by its remote solitude, stunning views and
abundant wildlife. The Lamar Valley is cut by the
Lamar River, a tributary of the mighty Yellowstone
River. The Lamar River has dozens of important
tributaries including Slough Creek.
The open land is sheltered by the towering
Beartooth-Absaroka range. This isolation provides
abundant moisture from snow melt, while the
volcanic ground provides abundant shrubs and
berries for wildlife. The Lamar Valley includes
echoes of an ancient petrified forest, fossilized
rocks are excellent habitats for a number of species.
Though often bypassed by tourists, The Lamar
Valley is a ‘metropolis’ for wildlife including: bears,
foxes, coyotes, bison, pronghorn, elk, moose,
smaller rodent species…
The most beautiful and controversial species in the
Lamar Valley is the Yellowstone Gray Wolf, which
was reintroduced to its native park habitat in the
1990s. Ranchers oppose the wolf’s reintroduction,
while biologists argue that wolves help strengthen
biological diversity in the park and act as important
predators in protecting a healthy balance of life in
Wildlife of Yellowstone
• Yellowstone's abundant and diverse wildlife are as famous as its geysers.
There are 67 species of mammals including 7 species of native ungulates
and 2 species of bears, nearly 300 species of birds, 16 species of fish, 4
species of amphibians, and 5 species of reptiles. In the following slides
we’ll be introduced to a few members of Yellowstone’s wildlife population.
• Mammals include:
• Grizzly and Black Bears
• Bighorn Sheep
• Mountain Goats
• Bison (Buffalo)
- Grizzly Bears are an emblem of Yellowstone, an ambassador of the park’s wild
- The mighty Grizzly Bear is identifiable by its distinctive hump and the grayish or
grizzled tips of its fur. Grizzlies have a terrific sense of smell.
- Height: 3 ½ feet at the shoulder
- Grizzlies only live in Wyoming, Idaho, Montana and Washington though their
historical range stretched to California and the Great Plains. The Greater
Yellowstone Ecosystem is home to over 700 Grizzly Bears
- Weight: Male (216-717 lbs.) Female: 200-428 lbs.
- Grizzlies can run at speeds of 30 miles per hour.
- In spite of their ‘ferocious’ reputation as killers, a grizzly’s diet consists mostly of
berries and nuts. They do not attack humans unless provoked, or a bear has
become habituated to human food. A fed bear is a dead bear because habituated
bears change behavior and become more aggressive.
- Grizzlies have a lifespan of twenty-to-thirty years. They have one of the lowest
reproductive rates of terrestrial mammals on the continent. Grizzly Bears do not
reach sexual maturity until they are four to five years old.
- On average females produce two cubs in a litter
- A Mother’s Love: Grizzly Mama Bear’s will do anything to protect their young, they
raise their cubs for two years
- The grizzly bear is an important force in the
ecological make-up of Yellowstone.
- The grizzly bear has a mutualistic
relationship with fleshy-fruit bear plants. As
the grizzly consumes the fruit, the seeds are
seeds are dispersed and excreted in a
germinal condition. This is an examine of
the circle of life in the park from the flora to
top of the food chain predator.
- While foraging for tree roots, plant bulbs or
ground squirrels bears stir up the soil. This
increases species richness in alpine soil
making nitrogen deep in the soil more
readily available for the environment,
therefore strengthening the soil and viability
of plants in the ecosystem.
- Bears are most solitary except during mating
season or when they are with their young.
- Bears eat elk, moose, pronghorn and other
carrion, squirrels and ground rodents. They
do not consider humans a source of food
and have mutual respect for humans. In fact
bears fear humans and try to avoid us.
Respect the bear. For bear safety tips check
- Bears hibernate on average for five months
a year. Warmer winters are disrupting the
delicate balance of a bear’s life cycle in
• The black bear is the most common and widely distributed bear species in North America.
• The Greater Yellowstone Ecosystem is one of the few areas south of Canada where black bears
coexist with the Grizzly Bear.
• Black bears can be black, brown, golden and even a reddish brown. So don’t judge a black bear
by its color.
• Black bears are smaller than Grizzlies, but what they lack in size they make up in agility. Black
bears are excellent climbers and are adapted to life in Yellowstone’s forests. Grizzlies are more
adept to foraging in open valleys.
• Their diet includes rodents, insects, elk calves, cutthroat trout, pine nuts grasses and other
• Black bears have an exceptional sense of smell. They have better eyesight than grizzly bears.
• Mate in spring; give birth the following winter to 1-3 cubs
• They are true hibernators. While Grizzlies choose to induce hibernation as an adaptation
mechanism, Black bears biologically have to hibernate as part of their cycle.
- Yellowstone provides a summer range for an
estimated 10,000 – 20,000 elk from 6-7 herds, most
of which winter at lower elevations outside the park.
These herds provide visitor enjoyment as well as
revenue to local economies outside the park. We
will go into the tourism economy of Yellowstone in
Unit Three of our Expedition
- Elk range in forest and forest-edge habitat,
feeding on grasses, plants, leaves and bark. They
are often found at Mammoth Hot Springs,
Gibbon and Sentinel Meadows and around Old
- Male (bull) elk weight around 700 pounds and
are five feet at the shoulder. Bulls have antlers,
which begin growing in the spring. Female (cow)
elk weight 500 pounds and are slightly shorter.
Calves average thirty pounds at birth.
- The Elk Rut is a dance of romance and ‘insanity’
each autumn in Yellowstone. Bull elk compete
for mates and to set up their harem. The sound
of the love bugle of a bull elk is truly haunting
Bison: ‘Give me a home where the Buffalo
• Bison are the largest land-dwelling mammal in North America. Males
average 1985 lbs. , while females weigh 1100 lbs. Both males and females
are dark chocolate-brown in color with long hair on their forelegs, head
and shoulders. Rarely bison are white. White bison are considered sacred
to Native American tribes.
• Calves are born after nine months of gestation and are reddish-tan at birth,
and begin turning brown after 2 ½ months.
• Both sexes have relatively short horns that curve upward
• All bison have a protruding shoulder hump between five and six feet tall.
• Large shoulder and neck muscles allow bison to swing their head side to
side to clear snow from foraging patches – making them hardy winter
- In spite of their size, bison are able to run
thirty five miles per hour. They are
excellent swimmers as well.
- They can jump over objects about five
feet high and have excellent hearing,
vision and sense smell.
- Bison are active during the day and at
- Bison are social animals that often form
herds, which appear to be directed by
- Bison primarily feed on grasses, sedges
and other grass-like plants in open
grassland and meadow communities.
- They often can be found in the Hayden
and Lamar Valleys.
- Yellowstone has an estimated population
of 4,600 bison in two breeding herds,
northern and central.
• Bison overpopulation is a major biological debate as ranchers fear
migratory bison will encroach on their rangeland, hurting cattle’s grazing
territory and infecting the herd with brucellosis. The NPS has resorted to
hazing to quell the natural migration of bison. This is culling practice is
based on unsound biological evidence. Bison do not transfer brucellosis to
cattle. Elk are known to infect cattle with brucellosis, but elk hunting is
critical to the Montana, Idaho and Wyoming economies, leading to a
stigma on bison. Bison and Wolves have been social issues in the Greater
Yellowstone area based on historical and social prejudices as well as
science and research. It is important to research through deductive and
inductive reasoning and hear all sides of an argument before making a
judgment on Yellowstone issues. Politics often plays a role that contradicts
the mission of the park: to protect and to preserve for the people. This is a
civics issue for park patrons and public servants. For more information on
the Yellowstone Bison controversy: Buffalo Field Campaign ; NPS Bison
• More info on brucellosis
Yellowstone Gray Wolf
- 26-36 inches high at the shoulder; 4-6 feet
long from nose to tail tip
- Males weigh 100-130 pounds; females
weigh 80-110 pounds
- Average lifespan is five to twelve years in the
- Wolves can be gray, black and white; gray is
the most common
- There are currently 400-450 wolves in the
Greater Yellowstone Ecosystem
- Wolves are able predators who feed
primarily on hoofed animals. In
Yellowstone, 90% of their winter diet is elk;
more deer is summer; eat a variety of
smaller mammals like beavers
- They mate in February and give birth to
average of five pups in April after a gestation
period of 63 days; young emerge from the
den at 10-14 days old; pack remains at the
den for 3-10 weeks unless disturbed.
Yellowstone Wolf Extermination and
• Wolf packs once roamed from the Arctic tundra to Mexico, but a loss of habitat
and extermination programs led to their demise throughout most of the United
States by the early 1900s.
• The gray wolf was an active participant in the complex Yellowstone Ecosystem
when the park was founded in 1872. At the time park management was a
nascent science and even biologists did not understand how ecosystems are
• Park officials set out in the 1870s to destroy Yellowstone’s wolf population
believing the predator was a danger to the vitality of the park. By the mid-1950s
Yellowstone’s wolf population vanished
• In the 1960s the National Park Service wildlife management policy changed to
allow populations to manage themselves. Many argued that wolves were critical
to the ecosystem’s ability to regulate populations of other mammals and create a
healthy balance in the park.
• In the 1960s and 70s, national awareness of environmental issues brought Yellowstone
and other wild lands to the forefront of public policy. In 1973 the Endangered Species
Act was passed to help protect at risk wildlife, including all wolf subspecies (1978) in the
lower 48 states except Minnesota.
• It is NPS policy to restore native species when possible leading to the controversial
proposal to reintroduce the wolf into the Yellowstone ecosystem.
• Wolves have traditionally been viewed as violent, aggressive predators that feed on
livestock. They also hunt elk and other carrion that game hunters target in hunting
season. Hunting licenses supply state income. Wolf reintroduction truly is a crossroads
of social science issues including geographical impacts of wolves on the land and
populations, economic factors (increase in park tourism, decrease in hunting license fee
income as elk populations decrease; revenue loss from livestock killed by wolves), and
the historical implications of wolves place in the ecosystem.
• From 1995 to 1997, 41 wild wolves from Canada and northwest Montana were released
in Yellowstone National Park. As expected, wolves from the growing population
dispersed to establish territories outside the park where they are less protected from
human-caused mortalities. The park helps ensure the species' long-term viability in
Greater Yellowstone and has provided a place for research on how wolves may affect
many aspects of the ecosystem.
Wolves as prey…
• In 2011, Congress gave hunters and trappers in
Montana and Idaho the right to hunt wolves that
had previously been protected under the
Endangered Species Act
• 366 wolves were killed in the first year of hunting.
• This remains a controversial topic as hunters argue
that the elk are dying because of the wolf. Wolf
advocates point out that the overpopulation of elk
is being naturally culled. Trophy hunters are upset
they are not allowed to hunt, since the wolf is
controlling the population effectively.
• Another valid argument against wolves is their
affect on agriculture. The debate will continue
• In spite of their big-bad reputation wolves are
remarkable creatures, who are loyal, smart, agile
Moose: The Solitary
- Moose are loners by nature who are known for
being ‘moody,’ truth is they are just solitary
warrior’s who like to keep to themselves. They
rarely travel with more than one or two other
moose companions, unless caring for their
- Moose are the second largest mammal in the
park after bison, weighing upwards of 1000
- Moose have a preferred diet of willow, aspen
and aquatic plants.
- They are excellent swimmers, often seen around
marshy areas of meadows, lake shores and along
- There are fewer than 200 moose in Yellowstone.
The population has declined in the last forty
years due to loss of old growth forest, hunting
outside the park and predators
Small, but mighty: wildlife that makes
- Pika Marmot
Yellowstone birds are wild and varied from migratory to
resident birds. The majestic trumpeter swan and dynamic
pelican are popular birds in the park
Trumpeter Swan Yellowstone Pelican
• PASSPORT STAMP – Geography
• We have completed our journey into the geographic wonders of
Yellowstone, a land shaped by time, erosion, uplift and volcanism.
Yellowstone is a dynamic biosphere, with intricate hydrologic systems,
mountains, plateaus, valleys and abundance of life from microbes to
the thundering bison.
• Next up on our Social Studies trek into Yellowstone, we will step into a
time machine and explore the history of Yellowstone National Park
• Websites used in this digital presentation include:
• All photographs are taken by Adele Lassiter, or free copyright sources
from NPS.gov and other license free sources.