2 volume
Tundra
T R A D I T I O N A
N E W
Tundra
OUR LIVING WORLD: EARTH’S BIOMES B a r b a r a A . S o m e r v i l...
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2 volume
Tundra
T R A D I T I O N A
N E W
Tundra
OUR LIVING WORLD: EARTH’S BIOMES B a r b a r a A . S o m e r v i l l
B O O K S
T R A D I T I O N
®
, I N
M A P L E
P L A I N ,
C H I L D R E N ’ S
M I N N E S O T A P U B L I S H I N G
TM
ABOUT THE AUTHOR
Barbara A. Somervill is the author of many books for children. She loves learning and sees every writing project as a chance to learn new information or gain a new understanding. Ms. Somervill grew up in New York State, but has also lived in Toronto, Canada; Canberra, Australia; California; and South Carolina. She currently lives with her husband in Simpsonville, South Carolina.
CONTENT ADVISER
Susan Woodward, Professor of Geography, Radford University, Radford, Virginia
4
In gratitude to George R. Peterson Sr. for introducing me to the beauty of creation —George R. Peterson Jr., Publisher, Tradition Books® Published in the United States of America by Tradition Books® and distributed to the school and library market by The Child’s World® [ACKNOWLEDGMENTS] For Editorial Directions, Inc.: E. Russell Primm, Editorial Director; Dana Meachen Rau, Line Editor; Katie Marsico, Associate Editor; Judi Shiffer, Associate Editor and Library Media Specialist; Matthew Messbarger, Editorial Assistant; Susan Hindman, Copy Editor; Lucia Raatma, Proofreaders; Ann Grau Duvall, Peter Garnham, Deborah Grahame, Katie Marsico, Elizabeth K. Martin, and Kathy Stevenson, Fact Checkers; Tim Griffin/IndexServ, Indexer; Cian Loughlin O’Day, Photo Researcher; Linda S. Koutris, Photo Selector For The Design Lab: Kathleen Petelinsek, design, art direction, and cartography; Kari Thornborough, page production [PHOTOS] Cover/frontispiece: Corbis. Interior: Animals Animals/Earth Scenes: 16 (Bradley W. Stahl), 38 (Studio Carlo Dani), 62 (Erwin & Peggy Bauer), 67 (Maria Zorn), 73 (McDonald Wildlife Photography), 81 (Breck P. Kent), 88 (OSF/Doug Allan); W. Perry Conway/Corbis: 41, 57; Corbis: 8 (Liz Hymans), 12 (Andrew Brown; Ecoscene), 15 (Wolfgang Kaehler), 20 (Dave G. Houser), 30 (Arthur Morris), 32 (Steve Kaufman), 33 (Eric and David Hosking), 42 (Charles Mauzy), 47 (Tom Brakefield), 54 (Lowell Georgia), 55 (Scott T. Smith), 59 (Kevin Schafer), 60 (Hubert Stadler), 64 (Joe McDonald), 84 (John Noble); Michael DeFreitas: 75; Dembinsky Photo Associates: 21 (Pekka Parvianinen), 46 (Darrell Gulin), 53 (Dominique Braud); Digital Vision: 28, 50, 83; Patrick Endres/Alaskaphotographics.com: 51, 52, 58, 69, 76, 78; Frank Lane Picture Agency/Corbis: 22 (Philip Perry), 80 (Roger Wilmhurst); D. Robert & Lorri Franz/Corbis: 35, 37; Getty Images/Brand X Pictures: 9; Darrell Gulin/Corbis: 48, 91; Wolfgang Kaehler: 27; A. Kuznetsov/Art Directors & TRIP Photo Library: 7; Photodisc: 18, 24, 26, 36, 39, 43, 61, 68, 70, 77, 90; Robert Pickett/Corbis: 66, 82; Crii Rad/Constantin Blanc/Corbis Sygma: 86; Galen Rowell/Corbis: 5, 11; Gary Schultz: 17, 44, 89; Kennan Ward/Corbis: 23, 34, 49; Peter Weimann/Animals Animals/Earth Scenes: 4, 29. [ L I B R A RY O F C O N G R E S S C ATA L O G I N G - I N - P U B L I C AT I O N D ATA ] CIP data available
Table of Contents
Table of Contents [Chapter One]
4 Defining Arctic and Alpine Tundra [ C h a p t e r Tw o ]
22 Focus on Key Species [Chapter Three]
32 Predators [Chapter Four]
43 Prey [Chapter Five]
51 Flora [Chapter Six]
59 Herbivores [Chapter Seven]
69 A Cycle of Life [Chapter Eight]
74 The Breeding Season [Chapter Nine]
82 The Human Touch 92
[Chart of Species]
93
[Index]
4
1
[Chapter One]
Defining Arctic and Alpine Tundra
Defining Arctic and Alpine Tundra
4
4 A snow leopard leaps over snowdrifts in the Himalaya Mountains. Her thick fur keeps her warm in winter. Like most snow leopards, this female cat lives alone. She is 4 feet (1.2 meters) long and weighs 80 pounds (36 kilograms),
A herd of Tibetan blue sheep keeps a watchful eye out for hungry snow leopards.
about the size of a big dog.
A herd of Hima-
? WORDS TO KNOW . . .
She hunts with skill and cun-
layan blue sheep
ibexes (EYE-beks-ez) a large
ning. She can bring down
paws the ground
variety of wild goats
Himalayan tahrs and ibexes
nearby. The leopard
tahrs (TARZ) long-haired mem-
equal to her own weight.
keeps downwind of
bers of the wild Asian goat fam-
the sheep. The
ily found only in the Himalayas
Today, her hunt leads her into a valley. The leopard
sheep neither hear
crouches down against the
nor smell her approach. She
snow. Her gray-spotted white
slinks forward, then leaps. The
fur blends in against snow-
herd scatters. They bound onto
capped rocks.
sheer, rocky cliffs to escape.
A snow leopard prowls the alpine tundra of Asia’s Himalaya Mountains.
5
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
?
The leopard’s
WORDS TO KNOW . . .
Tundra supports fewer
biomes (BYE-ohmz) large
search for food has
types of plants and animals
ecosystems in which the
failed. She’ll try
than most other biomes. It
plants and animals are adapted
again, but next time,
seems like a barren, heartless
to a particular climate or physi-
a hare becomes the
land. Yet it is filled with life.
cal environment
target. Hares are
About 1,700 different plants
ecosystems (EE-koh-siss-tuhmz)
easier to catch than
grow in arctic and subarctic
communities of plants and
sheep. They also
ecosystems. These include
animals and their relationships
make a decent meal.
grasses, sedges, lichens, wild-
with the surrounding environ-
Snow leopards can’t
flowers, and shrubs. The plant
ments
be choosy about
varieties growing within each
what they eat. There
region depend on soil quali-
is too little prey available high
ty, weather, and water supply.
in the Himalayas of Asia.
There are far fewer animal species than plants. The
Two Types of Tundra
number of animals depends
4 Tundra comes from the
on available food. The ability
Lapp word tundar. It means
to adapt to harsh weather
“treeless plain”—an accurate
also limits the variety of
description. Only short, stunt-
tundra animals.
ed trees survive the rugged
6
Tundra exists in two
tundra climate. Those trees are
forms, alpine and Arctic.
hard to find.
Alpine tundra covers A tree like this one is a rarity on Siberian tundra. Most tundra trees hug close to the ground.
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
mountain areas above
rainfall, and short
the tree line. Arctic tundra
growing seasons.
tree line (TREE LINE) the maxi-
occurs within or near
Few humans live
mum elevation at which trees
the Arctic Circle. Both
in tundra environ-
will grow
feature cold climates, little
ments.
?
WORDS TO KNOW . . .
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
Alpine Tundra
tudes—about 8,500 feet (2,700 m). Usually, alpine
4 Alpine tundra is found in
tundra starts between 10,000
Africa, Asia, Europe, South
and 11,000 feet (3,050 and
America, and North America.
3,350 m) in altitude.
Tundra begins at
At high altitudes, tempera-
different altitudes
tures drop and high winds
altitudes (AL-ti-toodz) eleva-
in every alpine sys-
whip the landscape. High alti-
tions above sea level
tem, depending on
tudes also have thinner air.
where trees stop
Animals have less oxygen to
?
WORDS TO KNOW . . .
growing. It starts above the
breathe. Plants make do with
tree line. In the Himalaya
lower levels of carbon dioxide,
Mountains, tundra begins at
the gas they need to live.
about 14,750 feet (4,500 m).
Many animals and plants
Rocky Mountain tundra to the
cannot adjust to thinner air
north may begin at lower alti-
or harsh weather.
In winter, alpine tundra can present a rather bleak landscape.
All alpine tundra ecosys-
Average alpine tundra
tems endure odd weather
temperatures range from –2°
patterns. Summer mornings
to 50° Fahrenheit (–19° to 10°
might start sunny and warm.
Celsius). Temperatures on
Yet the day could end with a
exposed cliffs and rocky land
snowstorm. Sometimes, the
drop much lower in winter.
snow falls so thick it creates a
Snowfall may be heavy, though
whiteout. People cannot see
the region is usually dry.
more than a few feet in front of them in a whiteout.
Alpine tundra animals find ways to cope with the cold.
Pikes Peak, Colorado, is one of the most frequently climbed mountains in North America.
9
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
75˚N
Bears hibernate. This means
at lower altitudes. They must
that they fill up on food in the
hunt food through the winter.
fall and sleep through the worst
Most alpine birds, including
winter weather. Wolves and
birds of prey, migrate south.
mountain lions move to forests
They head for warmer weather.
Arctic Ocean
Arctic Ocean
GREENLAND
Arctic Ocean
60˚N
E U R O P E A S I A
45˚N
N O R T H A M E R I C A
Atlantic Ocean
30˚N
15˚N
Pacific Ocean
Pacific Ocean
A F R I C A
0˚
S O U T H A M E R I C A
15˚S
Indian Ocean AUSTRALIA
30˚S
N 45˚S Alpine Tundra
60˚S 165˚W
150˚W
135˚W
120˚W
105˚W
90˚W
75˚W
60˚W
45˚W
30˚W
15˚W
0˚
Alpine tundra regions of the world
10
15˚E
30˚E
45˚E
60˚E
75˚E
90˚E
105˚E
120˚E
135˚E
150˚E
165˚E
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
Alpine Tundra around the World 4 In Asia, alpine tundra is found in the Himalaya Mountains, the Plateau of Tibet, and on Fuji, the highest mountain in Japan. The Himalayas include Mount Everest and dozens of other peaks rising more than 20,000 feet (6,100 m). The Himalayan alpine tundra provides homes for several unusual animal species, 0˚
Pink rhododendrons splatter color across the Kama Valley near Mount Everest.
including tahrs, yaks, and
stretch through Italy, Switzer-
snow leopards. Himalayan
land, Lichtenstein, Austria,
alpine shrubs include juniper
and France). In most regions
and rhododendron. Mosses,
of the Alps, the tree line lies
sedges, and lichens also grow
from about 5,000 to 9,000
at tundra heights.
feet (1,500 to 2,740 m). The
European alpine tundra exists in the Alps (which
tree line can lie at different altitudes on parts of the same 11
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
The Swiss Alps are famous for ski resorts and stunning mountain landscapes.
12
mountain. Lush meadows
grasses. Few large predators
fill high valleys in the Alps.
remain in the Alps. Most have
Clusters of edelweiss sprinkle
been overhunted or forced out
white blooms among meadow
of the region. Golden eagles
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
patrol the skies above alpine
WORLD WILDLIFE FUND IN
meadows. They hunt for
THE NEWS
rodents and small birds.
The World Wildlife Fund (WWF) is
Loss of predators in a
returning bears, wolves, wolverines,
region such as the Alps de-
and lynx to Europe’s Alps. For many
stroys nature’s balance. With-
years, the Alps had no large predators.
out predators, plant-eater
The WWF blames this on bad rumors.
populations grow out of con-
People in European communities grew
trol. Deer, for example, pro-
up on stories of evil wolves and dan-
duce young every year. Too
gerous bears. Europeans believed that
many deer eat too many plants
it was good to kill these predators.
and damage forests. The Alps
So far, the WWF has reintroduced
need predators, such as bears
two predator groups in Europe. Lynx
and wolves, to reduce the
now live in the Swiss mountains. A
number of plant eaters.
new group of bears prowls the
Only a few places in
Austrian Alps.
Africa have alpine tundra. One of these is Mount Kilimanjaro in Tanzania. Kilimanjaro’s alpine zones contain stumpy scrub trees and giant-sized plants, such as senecios and lobelias. 13
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
Crowned eagles and
cover the land. The most
The earth’s largest herb grows
lammergeiers circle
common grass-eating animals
in the Andes at 13,000 feet
the air looking for
found in the altiplano are
(3,965 m) above sea level. The
prey. Elands and
South American relatives of
herb is the Puya raimondii.
klipspringers,
camels: vicuña, llama, alpaca,
When the plant is about 100
types of antelopes,
and guanaco.
years old, it flowers for the
browse on clumps
first time—then dies. The
of tundra grass.
!
WOULD YOU BELIEVE?
puya plant can reach 35 feet
South Amer-
In North America, alpine tundra occurs in the northern Appalachian Mountains and in
(10.7 m) tall, and the flowers
ica’s Andes Moun-
the Rocky Mountains. Most
can have a diameter of up to
tains spread more
Appalachian mountains lie too
8 feet (2.4 m).
than 4,500 miles
low to have alpine tundra
(7,240 kilometers)
zones. Tundra is limited to
down the western
small patches on the higher
The Rocky Mountains by Larry
side of South
peaks of New England. Mount
Bograd (Benchmark Books,
America. They fea-
Katahdin, Maine, which rises
2001) presents a full picture of
ture the altiplano,
5,268 feet (1,606 m), supports
the Rockies. The author explains
which is Spanish for
tundra lichens, sedges, and
the different ecosystems found
“high plains.” The
mosses above the treeline.
in the mountain range.
altiplano is alpine
READ IT!
tundra of a slightly
14
The Rockies stretch from Canada to the southwestern
different kind. There are no
United States. Rocky Mountain
trees, but prairielike grasses
tundra supports bumblebees
Strong winds mold snow into drifts on the tundra in Manitoba, Canada.
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
and butterflies, grizzly bears,
Arctic tundra in January.
mountain sheep and mountain
By then, winter has gripped
goats, marmots, pikas, and
the land for several months.
rosy finches. Each summer,
Sunlight casts a faint
wildflowers sprinkle alpine
glow that lasts barely
meadows with color. Winters
an hour each day.
latitude (LAA-tih-tood) the
find the same landscape blan-
Wind whips the land
distance a point is north or
keted by several feet of snow.
day and night.
south of the equator; lines
Arctic Tundra 4 Nothing is as bleak as
Arctic tundra ranges from 55° to 70° north latitude.
?
WORDS TO KNOW . . .
of latitude run parallel to the equator
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
Tundra lies in Russia, Alaska,
arrival of millions of migrat-
Canada, and Greenland. It is
ing birds, such as tundra
also found in Iceland, Norway,
swans, snow geese, ducks, and
and Sweden.
plovers. Migrating birds come
Arctic tundra has two distinct animal popula-
to lay their eggs and raise their young on the tundra.
WOULD YOU BELIEVE?
tions: summer-only
Refrigerator temperatures run
visitors and perma-
swarms. They plague musk
between 32°F and 40°F (0°C to
nent residents.
oxen and caribou with con-
4°C ). Freezers range from 0°F
Summers see the
stant buzzing and biting.
!
to 10°F (–18°C to –12°C ). Arctic tundra temperatures can drop to –60°F (–51°C ). That’s cold!
Insects breed in huge
Midnight sun makes an eerie appearance over Alaska.
However, the billions of
ground. Their short height
insects feed millions of nest-
protects them from strong
ing birds.
winds and cold temperatures.
About 1,700 different
Summer plants reproduce
kinds of plants live in Arctic
in a hurry. Flowers must
tundra regions. Most are
bloom and produce seeds
sedges, mosses, and lichens.
during the six- to nine-week
Thick clusters of grasses
growing season. Ever-present
sprout up near icy streams.
winds and helpful plant eaters
About 400 types of wild-
carry the seeds across the
flowers huddle close to the
land. Of the millions of seeds
This Arctic tundra is located in Greenland.
17
An Arctic fox’s fur turns white in winter. It helps the fox blend in with its surroundings so that prey cannot see the fox approaching.
produced, only
south. Bears and Arctic
National Geographic’s White
a few actually
ground squirrels glut them-
Wolf [ASIN: 6304475993] allows
become plants.
selves with food. Then they
WATCH IT!
viewers an inside look at life in
Winter comes
sleep in their dens until
a wolf pack. Learn about the
early in the Arctic,
spring. Rodents nestle in
trials and challenges of tundra
usually by Septem-
underground holes called
wolves in their natural habitat.
ber. Migrating birds
burrows to keep warm.
have already fled
Insects and their eggs lie
18
PROFILE: PERMAFROST Plant roots struggle to find space in the
extra-thick winter coats.
thin layer of tundra soil. The roots can-
The fur has two layers. The
not reach deep into the soil. A solid
short fur close to the skin
layer of permafrost blocks their path.
keeps the animals warm.
Permafrost is permanently frozen
Arctic foxes’ white coats blend
rock or soil. Even when summer tem-
with the snow to help them
peratures climb higher, permafrost
hide from the prey they
remains below 32°F (0°C). Permafrost
are hunting.
lies under about one-fourth of earth’s
20
Wolves and foxes grow
Many rodents live in
land. Permafrost in the Siberian region
underground burrows.
of Russia reaches as deep as 5,250
But they can dig only a
feet (1,600 m).
short way. Soil deeper than
[ D e f i n i n g A r c t i c a n d A l p i n e Tu n d r a ]
2 or 3 feet (.6 or .9 m) is
chicks. Life races
frozen solid. Rodents line
against the coming
aurora borealis (uh-ROR-uh
their dens with fur or
winter, when sting-
bor-ee-AL-iss) lights that
plants to add warmth.
ing cold will again
appear in the northern sky
grip the land.
near the Arctic; the aurora is
Insects head underground for the winter,
?
WORDS TO KNOW . . .
the result of flares on the sun
too. Some insects have a special chemical in their blood. The chemical works like antifreeze in a car. It allows the insects to survive intense cold. When spring approaches on the Arctic tundra, snowdrifts melt and icy streams rush against their banks. The aurora borealis fills the sky with dancing lights. Summer welcomes millions of butterflies, bees, mosquitoes, and flies. Vast flocks of tundra swans, Canada geese, and ducks feed their hungry The aurora borealis lights up Norway’s nights with nature’s most beautiful light show.
21
2
[ C h a p t e r Tw o ]
Focus on Key Species
Focus on Key Species
22
thousands that will give birth this June. Snow still covers the hillsides, but the doe finds a patch of bare ground. She gives birth
4 It is early June. A female
to twins—a rare occasion. Most
caribou arrives at the spring
caribou births produce only
birthing grounds. She is one of
one calf.
Caribou herds migrate along the same paths their ancestors used hundreds of years ago.
Within minutes, the twin
The herd’s size offers the
calves rise on shaky legs. After
calves some protection. They
just hours, they walk. By the
are among thousands of calves
next day, they have enough
born to the George River herd
strength to travel with the
in Quebec and Labrador,
herd. Young caribou must
Canada. The herd numbers
keep up with the adults.
about 500,000 animals and
Wolves and grizzly bears look
is one of the three largest
for stragglers. Even golden
caribou herds in the world.
eagles have been known to
Predators will not attack
take caribou calves.
when so many adults surround
Caribou calves must be able to move with the herd when they are only a few hours old.
23
the calves. Caribou antlers are too dangerous, even for hungry wolves.
Keystone Species of the Arctic 4 Caribou, or wild reindeer, are keystone species of the Arctic tundra. They play a major role in the tundra biome. Without caribou, many other animals would not survive. Wolves and bears hunt young, old, and injured caribou. Predators must eat to live. Caribou provide their food. Predators also keep the herd healthy by weeding out weak animals. Two other predators attack caribou—mosquitoes and flies. As many as 2,000 A male caribou sports huge antlers that become serious weapons in a fight.
[Focus on Key Species]
flies have been counted
?
WORDS TO KNOW . . .
Keystone Species in Alpine Tundra
carcass (KAR-kuhss) the body
4 A keystone
carrion (CAH-ree-uhn) dead or
species in alpine
rotting flesh
eat their fill, the dead cari-
tundra is the pika.
feces (FEE-seez) solid waste of
bou’s carcass supports other
Pikas belong to the
an animal or human
animals. Blowflies lay live
rabbit family. They
larvae (LAR-vee) insects at the
larvae on dead flesh.
live in the Himala-
stage of development between
Carrion feeders, such as
yas, the Rockies,
eggs and pupae when they
gulls, jaegers, and Arctic
and in most alpine
look like worms
foxes, pick at the remaining
locations. Pikas pro-
meat. No part of a dead cari-
vide wolves with
bou goes unused. Even dis-
about half their food
Caribou travel 800 miles (1,290
carded antlers provide food
supply. Snow leop-
km) a year through an incredi-
for porcupines.
ards, brown bears,
bly demanding ecosystem.
steppe eagles, and
Learn more about caribou at
deposit feces along their
goshawks also
these Web sites: http://www.
paths. This waste carries
stalk pikas.
environmentyukon.gov.yk.ca/
on one buck. Flies and mosquitoes suck blood. It is their food. Once wolves or bears
As caribou travel, they
seeds and spores of plants
Pika burrows
of a dead animal
LOOK IT UP!
fishwild/caribou.shtml and
the caribou ate. The caribou
provide homes for
http://idahoes.fws.gov/Fact/
help spread plant life across
small birds, such as
Caribou.html.
the tundra.
ground jays and 25
The pika’s sharp claws scratch away soil. This action keeps soil fresh and increases plant growth. Pikas eat plants. They collect and store leaves and grasses in small haystacks. Like caribou waste, pika waste spreads plant seeds through the ecosystem. Pocket gophers are a keystone species of the Rocky Mountain alpine tundra. They provide the same services to an alpine biome as Asian pikas. They dig burrows almost continuously. Pocket gophers turn soil and The pika is a favorite food of many tundra predators.
26
spread seeds through feces. Like squirrels and mice,
snowfinches. Lizards like
gophers are rodents. They’re
pika burrows, as well. These
not much of a meal, but hun-
animals don’t bother pikas.
gry predators do eat them.
A grizzly bear mother must teach her cubs how to find edible berries, nuts, and roots in the tundra.
[Focus on Key Species]
Umbrella Species
tion over other
?
WORDS TO KNOW . . .
creatures. For
endangered (en-DAYN-jurd) on
4 Governments pass laws
example, a grizzly
the edge being completely
to protect endangered or
bear’s home area
wiped out; few members of a
threatened species. Legal
ranges from 70 to
species still surviving
protection may outlaw hunt-
400 square miles
threatened (THRET-uhnd) at
ing an animal or digging up
(181 to 1,036 sq
risk of becoming endangered
a plant. It may limit roads
km). Protecting a
that run through a territory.
grizzly bear from hunting or
Laws may punish people for
loss of habitat covers its
killing endangered animals.
entire range. Many other ani-
An umbrella species is
mals and plants live within
a protected animal or plant
that territory. When the
that spreads its legal protec-
bear’s territory is protected,
[Focus on Key Species]
those plants and
umbrella species. So do
Discover everything you need to
animals share in
wolves and caribou. Bears and
know about grizzly bears. Read
that protection.
wolves roam large territories.
READ IT!
Grizzly Bear by Alvin and
Grizzly bears
Laws protect these predators.
Virginia Silverstein (Millbrook
are not the only
That protection spreads out
Press, 1998).
umbrella species of
like an umbrella over the
the tundra. Other
tundra biome.
!
WOULD YOU BELIEVE?
tundra bears, such
Flagship Species
Most bears are omnivores. That
as Asiatic black
means they eat both meat and
bears and polar
4 Flagship species star in
plants. A hungry grizzly can get
bears, also serve as
television specials. They have
into a feeding frenzy. It may eat 200,000 berries in one day!
A lone male wolf crosses open ground. He will live alone until he finds a mate, and the pair will then start a pack of their own.
Web sites dedicated to them.
Governments pass laws to
They create interest, emotion,
protect these popular species.
and money. In the tundra,
Flagship species help
flagship species include
preserve an ecosystem. Like
wolves, polar bears, lynx,
an umbrella species, their
and grizzly bears.
protection spreads over a
Saving a flagship species
region. Their problems
interests people in several
become “news.” The more
ways. People form organiza-
people who understand issues
tions to save polar bears and
facing an ecosystem, the
caribou. They “adopt” wolves
more likely those problems
that live in protected habitats.
will end.
A polar bear and her cub hunt ring seals on the pack ice in Manitoba. They find the seal by scent and then pounce a hole in the ice to catch their prey.
29
[Focus on Key Species]
Indicator Species 4 An indicator species mea-
ner bears are showing scientists how warmer earth temperatures affect the tundra.
sures the overall health of an
Plants make excellent
ecosystem. Scientists believe
indicator species for both
that polar bears are an indica-
Arctic and alpine tundra.
tor species of the Arctic tun-
Some lichens and sedges will
dra. Polar bears live on land
grow only under certain condi-
but hunt and travel in the seas.
tions. They need the right
They pursue ringed seals by
amount of water and sunlight,
walking out on solid ocean
and a specific environment to
ice. They find the seals living
grow. These plants react to
under the ice.
reduced or excess rainfall or
Scientists see a trend
snowfall. They do not grow
toward smaller, thinner, hun-
in polluted environments.
grier polar bears. They believe
Less plant growth shows
this trend results from warmer
problems in an ecosystem.
earth temperatures. Warmer
Most tundra plant eaters sur-
seas mean that solid ice forms
vive on sedges and lichens.
later. Polar bears cannot hunt
If ecosystem problems are
seals until solid ice forms. Less
not fixed, the plants will not
ice means shorter hunting sea-
grow. Animal species that
sons for polar bears. The thin-
eat the plants will suffer.
Lichens cling to tundra rocks like rust to an old car.
31
3
[Chapter Three]
Predators
Predators
32
birth to larger, healthier babies. A breeding pair of snowy
4 Tundra life spins in an
owls protects its nest in a hol-
ever-widening cycle. Five extra
low. This year, the female laid
warm days in Siberia, Russia,
seven eggs. All hatched into
lengthen the growing season
healthy, squawking owlets.
one year. Plentiful grasses and
Seven hungry owlets demand
wildflowers fatten voles and
constant food. Luckily, the
lemmings. In turn, these
healthy vole and lemming
plump rodent mothers give
populations provide food for
[Predators]
the owl family. Without Siberia’s five extra warm days, it would normally take a breeding pair of snowy owls two years to produce and raise seven healthy fledgling owlets. Snowy owls are birds of prey. They eat animals. Unlike most other owls, snowy owls
PROFILE: GYRFALCONS
hunt in daylight. Successful
Gyrfalcons are the largest falcons. These
hunts at dawn and dusk feed
aggressive hunters may be white, light
hungry mouths.
gray, or brown-gray in color. They live
The owlets grow quickly.
along rocky Arctic coasts, but they catch
By early fall, they have a full
their prey on open tundra. Gyrfalcons
set of feathers and can hunt
hunt gulls, snow geese, ptarmigans,
for themselves. Mild weather
and ducks.
and plentiful food allow snowy
Today, 1,650 to 2,650 breeding pairs
owls to stay on the tundra all
of gyrfalcons live in northern Europe.
winter. This year’s success
Laws protect gyrfalcons in the wild.
came from five extra warm
However, poachers, or illegal hunters,
days.
still capture and sell the birds. Live adult
Other birds of prey also live in alpine and Arctic Snowy owls find plenty to eat in the tundra, including lemmings, ground squirrels, mice, and hares.
gyrfalcons are sold illegally at prices ranging from $10,000 to $100,000.
33
A bald eagle fishes for salmon in an icy Alaskan river.
tundra. Hawks, eagles, fal-
animal eats. Predators that eat
cons, jaegers, and merlins fare
a variety of foods have a better
well in the tundra ecosystem.
chance of survival. Snowy owls
There are plenty of small
prefer voles and lemmings,
rodents and birds for them
but also eat ducks, ptarmi-
to eat.
gans, hares, and geese. Bears
Food Supply
34
fish for salmon in icy tundra rivers but will eat berries,
4 The success of a predator
nuts, flower bulbs, insects,
species depends on what the
rodents, and lizards.
[Predators]
Some predators hunt for food but will also eat carrion if they find it. Foxes and wolverines dine on the leftovers of other predators. Polar bears hunt ringed seals, but they eat only the blubber. An Arctic fox happily eats the remaining meat. Eating rotting meat seems disgusting. However, nature
A wolverine digs a storage pantry for its leftovers. If today’s hunt fails, it will eat last week’s caribou.
does not waste food. Every
food for large cats, bears,
part of a carcass feeds some-
wolves, and foxes.
thing, whether it is fly larvae,
Big cats from
!
WOULD YOU BELIEVE?
foxes, or voles that gnaw on
alpine tundra
Most predators kill only what
bones.
regions include
they can eat right then. This is
snow leopards,
not true of wolverines. They
mountain lions, and
hunt with future meals in mind.
4 At the top of the food
lynx. Big cats hunt
Wolverines store extra meat
chain are large predators.
by stealth. They
underground. When prey is
Other than humans, large
sneak up on their
scarce, they choose a meal from
predators have few enemies.
prey. When in
their underground “freezer.”
The tundra provides enough
range, they leap on
Top of the Food Chain
35
Cougars, also called mountain lions or pumas, live in many different biomes. They are the largest predators in the Andes alpine tundra. In North America, cougars roam the Rocky Mountains. Cougars eat rodents, but they prefer wild sheep or deer. The smallest tundra “big” cat is the lynx. Lynx weigh between 15 and 25 pounds (7 and 11 kg). At one A cougar takes a refreshing dip in an alpine tundra pool. Cougars, unlike house cats, do not mind a dip in a spring.
time, lynx lived in 21 of the
their targets. Big
than one thousand lynx live
Cougars can spring 18 feet
cats use lightning
in only four states: Washing-
(5.5 m) from the ground to a
quickness to catch
ton, Montana, Colorado, and
cliff. Along the ground, they
prey. Sharp claws
Maine. Other types of lynx
can cover 40 feet (12 m) in
and powerful teeth
exist in Siberia, Spain,
one long jump.
bring the prey to
Europe, and Central Asia.
the ground.
Lynx do well in both Arctic
!
WOULD YOU BELIEVE?
36
lower 48 states. Today, fewer
[Predators]
and alpine tundra ecosys-
about half that weight. Polar
tems. They eat mostly
bears hunt ringed seals and
hares, rabbits, and rodents.
bearded seals by smell. They
Bears, Wolves, and Foxes
pound on the ice above a seal’s home
LOOK IT UP!
4 Bears come in large, larg-
to break the ice.
Learn more about lynx around
er, and largest. Polar bears are
Polar bears do not
the world. Access lynx links
the biggest land carnivores.
drink water. They
at http://lynx.uio.no/jon/lynx/.
Males average 1,200 pounds
get water from seal
(544 kg), and females are
blubber. At times,
?
WORDS TO KNOW . . .
carnivores (KAR-nuh-vorz) animals that eat meat
This lynx is at full stretch as it prepares to pounce on its prey.
37
Tibetan, black bears are tiny compared to polar bears. Adult males usually weigh less than 400 pounds (181 kg). Females weigh from 110 to 275 pounds (50 to 125 kg). Himalayan black bears are omnivores. They eat fruit,
bees’ nests, insects, rodents, and carrion. They travel across alpine tundra only during the summer. Then berries are plentiful, and bees’ nests are filled with honey. In winter months, they live at lower altitudes. Himalayan black bears are a rare sight. These shy bears live well away from towns and villages in Tibet and Nepal.
Brown bears live in North America, Europe, and Asia.
polar bears also eat
Grizzlies are brown bears.
omnivores (OM-nuh-vorz)
young walruses,
In the Arctic, male brown
animals that eat both plants
grass, seaweed, and
bears weigh between 500 and
and meat
carrion.
1,320 pounds (227 and 600
?
WORDS TO KNOW . . .
Himalayan, or 38
kg). In alpine regions, brown
These grizzly cubs must learn how to fish for salmon. Grizzlies glut on salmon to add body fat for a long Arctic winter’s sleep.
[Predators]
bears weigh about 200 pounds
bou. They will also hunt the
(91 kg) less.
young of those species.
Grizzlies fishing for
Wolves live and hunt in
salmon are popular images
groups called packs. Wolves
on tourist posters. However,
inhabit both types of tundra.
most grizzlies eat the carrion
The pack moves toward a
of moose, elk, deer, or cari-
herd of prey. They single out
[Predators]
young, injured, or very old
summer-only lives. Midges,
animals to attack. Wolves
flies, and mosquitoes attack
may also hunt alone when
wild animals and humans
the prey is small, such as
alike. Some tundra insects,
hares, marmots, or voles.
such as wasps and dragon-
Arctic foxes spend sum-
flies, prey on other insects.
mer months alone, but they
At one level, insects are
collect in packs during the
fierce predators. At another
winter. They hunt small
level, they are primary prey
mammals, such as
for birds and rodents. Many
hares and lem-
wading birds and songbirds
insectivores (in-SEKT-uh-vorz)
mings. Arctic foxes
are insectivores.
animals that eat insects
also eat dead fish
Among horseflies and
and carrion. They
mosquitoes, only the females
?
WORDS TO KNOW . . .
often eat leftovers after bears
suck blood. Males drink
finish with a carcass.
plant juices or eat pollen.
Bloodsuckers
sharp mouths that cut easily
4 The hungriest and
through animal hides. In the
peskiest tundra predators
Arctic, flies and mosquitoes
are swarms of insects. They
plague caribou.
make a serious impact on the ecosystem during their 40
Mosquitoes and flies have
Many flies and beetles eat carrion. They get rid of
[Predators]
While this scene seems brutal, wolf packs actually keep deer populations healthy. They fell old, sick, or weak deer from the herd.
41
Mosquitoes swarm around this moose, caught taking a dip to get rid of the pesky insects.
42
rotting carcasses, dung (ani-
their eggs on carrion. The
mal feces), and other animal
young, called maggots, eat
waste from the tundra.
rotting flesh until they
Blowflies, for example, lay
become adult flies.
4
[Chapter Four]
4 A small colony of
main protection from
Prey
Prey
on a boulder overlooking the meadow. The other marmots do not go far. Their
hoary marmots munches on grasses in an alpine
?
WORDS TO KNOW . . .
meadow. The colony male
colony male (KOL-uh-nee
heads the group. He stands
MALE) the head or leading male of a group of marmots
Marmots, like pikas, are important members of the tundra community. They provide food for prey and distribute plant seeds.
43
Hoary marmots in Denali National Park, Alaska, form part of the complex cycle of life in tundra environments.
predators is a quick exit into
a dozen or so animals. If
their burrow.
food is scarce, they live in
Marmots live where
44
small families that consist
alpine meadows provide food
of a male, female, and recent
and rocky slopes offer protec-
young. Marmots hibernate
tion. Where food is plentiful,
during the winter. They begin
marmots live in colonies of
sleeping in September or
[Prey]
October and emerge from
prey. Most birds and insects are
their dens in early May.
summer residents. That leaves
Overhead, a golden eagle
the few birds that live perma-
circles. The colony male spots
nently on the tundra—along
the eagle. He lets out a shrill
with rodents, hares, and pikas—
whistle. Suddenly, the other
as prey.
marmots stop eating and dash
Ptarmigans live comfort-
for the burrow. They know by
ably in tundra ecosystems all
the male’s call that the preda-
year. Their feathers
tor is a golden eagle. Each call
change color with
identifies a different enemy.
the seasons. Winter
camouflage (KAM-uh-flahzh)
white coloring
coloring that blends in with
his watchdog role seriously.
makes them nearly
the surroundings
He shrieks when any other
invisible against the
ptarmigans (TAHR-mih-ganz)
animal comes near, even if
snow. In the sum-
game birds similar to grouse
there is no danger. For mar-
mer, they are speck-
mots, danger comes from
led brown. If they don’t move,
eagles, coyotes, lynx, bears,
they can’t be seen. Camou-
and wolverines.
flage is the ptarmigan’s only
The colony male takes
Limited Fare
?
WORDS TO KNOW . . .
protection from predators. Rodents make up the
4 Neither alpine nor Arctic
largest year-round prey group.
tundra offers much variety in
Rodents range from small 45
An Arctic ground squirrel will pass the tundra winter in a warm, underground burrow.
voles to large muskrats and
many as 50 tunnels and
porcupines. Most rodents dig
dozens of rooms.
burrows with several entries,
46
Lemmings are tundra
rooms, and escape hatches.
rodents that produce many
Arctic ground squirrels such
young. A female has her first
as marmots live in colonies.
litter in March. From then on,
Their burrows may have as
she produces five or six more
[Prey]
litters before the next winter.
Snowshoe hares run 27 miles
An average litter has four to
(43 km) per hour in short
eight young. Before female
bursts. They can cover 10
lemmings are a month old,
feet (3 m) in one jump. Like
they can produce litters.
Arctic foxes, snowshoe hares
Within one summer, a male
wear white coats in winter
lemming may be a father,
and brown for the
grandfather, and great grand-
summer. Their col-
father—several times over!
oring helps the
A pair of lemmings and three
hares “hide” on
generations with six females per
open ground.
litter may produce as many as
Most tundra predators eat lemmings. Because lemmings usually weigh only about 2
!
WOULD YOU BELIEVE?
4,000 young in one year.
ounces (57 grams), it takes several lemmings to make a meal. An adult snowy owl eats a dozen lemmings a day. Snowshoe hares, Arctic hares, and pikas are slightly larger prey. Hawks, foxes, lynx, wolves, and coyotes all hunt hares. Hares evade predators by running, hopping, and ducking down their holes. A snowshoe rabbit’s white coat blends in with the surrounding snow. A quick getaway saves this bunny from becoming breakfast.
47
WATCH IT! Living Planet: The Frozen Earth with David Attenborough (BBC/Time Life Videos, 2001) takes viewers from the peaks of the Andes to the Arctic.
An elegant tundra swan stretches its wings on a Canadian tundra pond.
A Summer Buffet
honks, hisses, and serious nips for their trouble. However, eggs or hatchlings are a different
The video explains how plants
4 Few predators
story. Weasels and mink are
and animals can survive such
willingly face an
nest thieves. They steal eggs
extreme weather conditions.
angry mother swan
and young birds while parent
or goose. They’ll get
birds are away hunting for food.
48
[Prey]
Weasels and mink have
per hour. They dive at speeds
plenty of company in hunting
of 230 miles (370 km) per
young birds. Birds of prey
hour. Few songbirds can escape
often hunt chicks and song-
a hunting peregrine falcon.
birds for food. The Arctic pere-
A type of jaeger lets other
grine falcon plucks songbirds
birds do its hunting. When
out of the sky. Falcons can fly
another bird of prey has
at speeds of 60 miles (97 km)
caught a meal, the jaeger
Can you find the two eggs that belong to these long-tailed jaegers? They are the same color as the ground, which protects them from predators.
49
Billions of insects buzz, click, and hum through the tundra summer. Insects provide food as eggs, larvae, and adults. Jaegers, plovers, buntings, and snow geese feed on insects. The role of prey seems brutal. Prey produce thousands, millions, perhaps billions of young, only to have their offspring eaten. The number of prey available limits the number of Black-backed gulls hover near a cliff, ready to steal fish from shy puffins.
50
predators in an ecosystem. Less prey equals fewer
grabs it from him in midair
predators. On the other
and eats it. Jaegers are not
hand, predators keep
the only feathered food
prey populations from
thieves. Pushy gulls and
exploding. Without this
skuas regularly rob prey
natural balance, the tundra
from shy puffins and
would be knee-high in lem-
skittish kittiwakes.
mings or grasshoppers.
5
[Chapter Five]
4 A caribou bends to
2,500 different varieties of
browse on low-lying lichens.
lichen that grow in the Arctic.
The lichens cover a rock the
Lichens have no roots and
size of a dinner plate. One
grow very slowly.
Flora
Flora
type of lichen that caribou find delicious is called reindeer moss. It is one of nearly
Male caribou move through tussocks of tundra grasses on their annual migration.
51
[Flora]
?
WORDS TO KNOW . . .
Lichens are
to mushrooms, gives lichens
alga (AL-juh) a simple one-
neither alga nor
strength. Lichen colors range
celled plant
fungus, but are
from orange-brown to gray-
fungus (FUHN-guhss) a flower-
instead a strange
green to off-white.
less, leafless type of plant
combination of both plant species.
READ IT!
Alga, the green
Plants of the Arctic Tundra
Arctic Tundra and Polar Deserts
slime found on
4 Arctic tundra plants face
by Chris Woodford (Raintree/
ponds, produces
serious challenges. Some-
Steck Vaughn, 2002) presents
food for lichens.
times, there are fewer than
a thorough picture of the dry,
The fungus, related
six or seven weeks in a grow-
barren tundra region.
Stunning saxifrage must bloom and produce seeds during the short Arctic summer.
ing period. Soil is shallow
winds. It also allows snow
and poor. Tundra climate
cover to protect the plants
will not support many types
during winter. Dwarf willows
of plants. There is too much
grow wide rather than tall.
cold and wind, and too little
They may reach only 4 inches
rainfall for most plants.
(10 centimeters) tall, but their
Almost all Arctic tundra
branches spread 15 feet (4.6
plants grow close to the
m) along the ground. The wil-
ground. Their low height
low’s roots stretch out an equal
protects them from bitter
distance underground.
Low-lying tundra plants hug the ground near this pond.
53
close together on many Arctic plants. Saxifrage, for example, traps a cushion of air within its leaves and stems. The difference between the air temperature outside and the temperature inside the cushion may be as great as 27°F (12°C). Leaves may also be leathery or hairy. Leathery saxifrage leaves retain water. The Arctic Arctic wildflowers cling to soil caught between rocks. They paint the landscape with yellows, reds, and pinks.
Leaf color and shape are key factors in plant survival. Many Arctic plants have dark green, red, or purple leaves.
climate is very dry. Holding water inside the plant may mean the difference between living and dying. Wildflowers paint the tundra with color during the
Dark leaves absorb
short, sunlit summer. Yellow
heat and light bet-
Arctic poppies and butter-
perennials (puh-REN-ee-uhlz)
ter than pale green
cups, vivid blue lupines, and
plants that have lifespans of
or yellow leaves.
rich, purplish red fireweed
longer than two years
Leaves tend to be
brighten the bare landscape.
thick and grow
Wildflowers are perennials
?
WORDS TO KNOW . . .
54
Bears go wild for delicious cloudberries. They can eat thousands in one day’s feeding frenzy.
DO IT! Plant a tundra garden. If you
with many small blooms. They
dra plants are moss-
live where snow falls, tundra
produce seeds by the millions.
es, sedges, and
wildflowers should grow in
The seeds are carried by birds
lichens. All three
your local soil. Most seed
and insects or by the wind.
grow close to the
catalogs have sections of
ground. Spongy,
wildflower seeds. Next spring,
nagoonberry shrubs sprout
green moss grows
you could have Arctic poppies,
near streams and ponds. Their
in wet areas, such
lupines, or fireweed growing
fruit feeds birds, bears, and
as bogs or marshes.
right outside your door.
hares. Animals spread berry
Sedges look like
seeds in their feces.
wild grass. They grow in thick
Bearberry, crowberry, and
The most common tun-
clumps, which protect fragile 55
[Flora]
roots from the cold. Lichens
gnarly, dwarfed trees to bril-
grow extremely slowly, but
liant wildflowers and dusty
there are plenty of them.
lichens. Like Arctic plants,
Lichens can be crusty or
alpine flora faces challenging
leafy. Caribou and musk oxen
conditions. Surprisingly, there
feed on sedges and lichens.
are far more Arctic tundra
Plants of the Alpine Tundra
Colorado alpine tundra supports just more than 300 types
4 Alpine tundra plants adapt
of plants. Alaskan Arctic tundra
to cold and wind much like
supports 1,400 plant varieties.
Arctic tundra plants. They
A region of stunted,
grow close to the ground with
dwarf trees often lies above
wide-spreading roots. They
the tree line. This region is
often have dark green, red,
called krummholz, which is
or purple leaves to absorb heat
German for “crooked wood.”
and sun. Hairy, leathery, and
Krummholz trees endure
woolly plants are found in
strong winds and bleak
many alpine regions. As in the
weather conditions. The wind
Arctic, wildflowers sprinkle
and weather twist and bend
alpine meadows with yellows,
the trees until they look like
pinks, and purples.
hunched-over skeletons.
Alpine plants range from 56
plants than alpine plants. The
Meadows lie in many
Wind, cold, and dryness stunt the growth of tundra trees. These trees are called krummholz, which is German for “crooked wood.”
alpine tundra valleys. The
America. The European
meadows have lush growths
Alps are home to soft pink
of grasses, shrubs, and wild-
alpen-roses and pure white
flowers. Rhododendron, an
edelweiss. Africa’s Mount
evergreen with clusters of
Kilimanjaro has supersized
pink, yellow, or white flowers,
wildflowers—giant senecio and
is a common alpine shrub. It
giant lobelia.
grows in Sweden, Norway, the
North America’s Rocky
Himalayas, and parts of North
Mountains have spectacular 57
Ripe Alaskan blueberries dangle from a branch.
meadows. Yellow buttercups
called tussocks. Grasslike
and dandelions, blue lupines,
sedges feature tiny green,
and bright pink shooting stars
brown, or blackish flowers.
dance among tall grasses. In
Mosses carpet stream banks
late summer, ripe bilberries,
and grow up tree trunks.
blueberries, and thimbleber-
And lichens, as in the Arctic,
ries weigh down branches.
grip tightly to rocks. While
Most alpine tundra has
58
not as beautiful as wildflow-
grasses, sedges, mosses, and
ers, these plants provide
lichens. The grasses grow in
food for alpine plant eaters
meadows and in clusters
throughout the year.
6
[Chapter Six]
Herbivores
Andes plains found at about
4 A bitter wind sweeps
sea level. There is little
across the Andes Mountains
oxygen at this height.
of South America. On a high
Vicuñas have adapted to
plateau, a herd of vicuñas
survive in these conditions.
browses on stunted grasses.
Their extra-large hearts
Vicuñas look like camels with
and lungs distribute oxygen
no humps.
to their blood.
Herbivores
This region is the puna— 13,000 feet (4,000 m) above
These camel-like creatures are vicuñas. They live in the high plains of the Andes.
59
Vicuñas graze on sedges in the Andes tundra.
Vicuñas move in small herds with a male leader, several females, and young. The
60
From Guanacos to Grasshoppers
herd feeds on grasses and
4 Herbivores eat plants.
low-lying plants. Vicuñas
The term comes from the
have sharp front teeth, used
Latin words herb (“plant”)
to rip tough grass from its
and vore (“eater”). Tundra
roots. Their top front teeth
plant eaters usually munch
wear down, but their bottom
on any plants they can
front teeth continue to grow.
find. There is not enough
This Dall ram has quite a rack of horns. Despite its size, Dall sheep are agile climbers on alpine slopes.
[Herbivores]
plant life for herbivores to be
tains. Regardless of their size,
fussy eaters.
cleft-hooved animals walk easi-
Large herbivores roam
ly on the narrowest paths. This
both alpine and Arctic ecosys-
feature helps them avoid preda-
tems. Most are types of cattle,
tors, such as cougars, wolves,
sheep, goats, or camels. Alpine
or bears.
plant eaters often have cleft
Musk oxen and caribou are
hooves. That means their
the Arctic’s biggest herbivores.
hooves are split in the middle.
Caribou travel in vast herds
Split hooves help the animals
along routes carved by their
climb rocky cliffs and moun-
ancestors hundreds of years
[Herbivores]
?
WORDS TO KNOW . . .
ago. Caribou browse
actually a form of lichen.
extinction (ek-STINGKT-shuhn)
on sedges and lich-
Musk oxen physically
the state of having no more liv-
ens. Their favorite
resemble small bison. They are
ing members of a species
meal is reindeer
broad chested and have long
moss, which is
hair. They prefer eating grass but will graze on most plants. Musk oxen were once plentiful in the Arctic. Their herds nearly fell to extinction in North America. In 1930, the United States Fish and Wildlife Service bought 34 musk oxen from Greenland. These beasts formed a core herd and lived on Nunivak Island, Alaska. By 1980, the musk oxen had divided themselves into three separate herds. Their population reached 400 animals. Today, musk oxen live in Alaska, Canada, Greenland, and Siberia. They thrive because their herds have legal Musk oxen nearly became extinct, but current conservation programs are saving this hairy Arctic dweller.
[Herbivores]
protection from hunters. Alpine tundra herbivores
PROFILE: YAKS Shaggy, scruffy yaks live high on the
differ by location. The Himala-
Plateau of Tibet in Asia. They have
yas have yaks, blue sheep, and
short, thick bodies and even shorter
ibex. Alpine ibex and chamois
legs. Their bodies are shaped to with-
live in Europe’s Alps. The
stand brutal winters at altitudes up to
Andes provide homes for
20,000 feet (6,100 m). Split hooves give
vicuñas and guanacos. Rocky
yaks traction on steep, icy ground. They
Mountain tundra has Dall
are surprisingly graceful when climbing
sheep, bighorn sheep, and
rocky cliffs.
mountain goats.
About 3,000 years ago, Tibetans caught yaks and tamed them. They
DO IT!
started herds of domesticated, or
Your family, scout troop, or class
tamed, yaks. The herds provided meat
can adopt a musk ox calf from
and skins for clothing. People milked
The Musk Ox Farm in Palmer,
yak cows and made cheese and butter.
Alaska. The calves live on the
Domestic yaks are as different from
farm and are raised by volun-
wild yaks as pet dogs are from wolves.
teers. Visit the Musk Ox Farm
Humans have overhunted wild yaks
Web site (http://www.musk
and have taken away their natural
oxfarm.org) to find out about
habitats. Fewer than 500 wild yaks
adopting a musk ox.
remain. Although laws protect yaks from hunters, poachers still kill them.
63
[Herbivores]
A delicate rosy finch provides a sweet song amid the tundra’s summer wildflowers.
64
[Herbivores]
Smaller herbivores on the
lect leaves, grass,
!
WOULD YOU BELIEVE?
tundra include birds, rodents,
and seeds through-
Arctic ground squirrels sleep
rabbits and hares, and insects.
out the summer.
through seven months of tun-
These animals eat whatever
They dry plant
dra winter. During warm
they find: grasses, flowers,
matter in cracks
months, they gorge themselves
mosses, lichens, sedges, and
between rocks.
on seeds, leaves, flowers,
seeds. Many store dried grass
Pikas eat heartily
berries, roots, and mushrooms.
and seeds for the long winter.
all winter long.
Arctic ground squirrels collect
Tundra songbirds have
Rodents make
food nearly 18 hours a day.
names as lovely as their songs:
up much of the
They usually eat at around
rosy finches, white-crowned
mammal population
lunchtime. The squirrels need a
sparrows, and snow buntings.
on the tundra. Lem-
thick layer of fat on their bod-
Songbirds prefer seeds and
mings, ground
ies by August if they are to sur-
plants but also eat insects.
squirrels, and voles
vive hibernation. Many ground
Most songbirds migrate south
dig passages
squirrels do not survive. Some
before snow falls.
through the shallow
die because they did not have
Arctic soil. Their
enough body fat. Others are
belong to the lagomorph fami-
relatives—pocket
uncovered and eaten by bears.
ly. Snowshoe and Arctic hares
gophers—do the
eat grasses during the summer.
same in alpine
In winter months, they chew
meadows. Pocket
lagomorph (LAHG-uh-morf) a
on twigs, buds, or bark. Pikas
gophers stuff their
mammal that gnaws plant food
prefer to store food. They col-
cheeks with roots
Rabbits, hares, and pikas
?
WORDS TO KNOW . . .
65
Even the coldest, bleakest habitat has it share of hairy, crawling creatures, like this common tundra insect called a springtail.
and scurry into their burrows
feeds some insects. Others
to eat. Voles are not as partic-
prefer young sprouts, bloom-
ular. They eat grass, leaves,
ing flowers, or plant liquids.
bark, or seeds.
Some flies lay eggs on rotting
Individual insects do not eat much food. However,
with animal carcasses, no
there are so many insects that
usable plant matter goes to
tons of plants wind up being
waste. Plants are also used to
devoured. Grasshoppers, may-
build nests.
flies, and several types of bee-
66
wood or plant matter. Just as
Butterflies and moths
tles feast on grasses and
deposit their eggs on leaves
leaves. Rotting plant matter
or plant stems. The eggs grow
A sulfur butterfly lands on a curled tendril from a low-lying vine.
[Herbivores]
into caterpillars. The cater-
tundra. They carry pollen
pillars eat the plant until they
from one flower to another.
spin cocoons. Weeks later,
The delivered pollen fertilizes
butterflies or moths emerge
wildflowers. Without pollen,
from the cocoons. The cycle
plants could not produce
begins again.
fruit or seeds. Without bees,
Bees drink nectar. They fulfill an important job on the
wildflowers might not grow in the tundra.
The bobcat seems to be winning the race against this snowshoe hare.
Herbivores play an
68
allow new plants to grow.
important role in tundra
They carry pollen from plant
ecosystems. They eat seeds
to plant. Herbivores also pro-
and spread them across the
vide predators with prey.
land through their feces.
This, too, is part of life on
They clear rotting plants and
the tundra.
7
[Chapter Seven]
4 Tundra wolves are top
ago in search of a mate. It
predators. In a pack, they can
is September. Soft snow fills
bring down a caribou with
the skies. The wolf’s coat
A Cycle of Life
A Cycle of Life
ease. On their own, they must find smaller and easier prey. A three-year-old male tundra wolf travels alone. He left his pack nearly one year
Hunting must be good for this lone wolf. Its coat is thick and its body is well formed.
69
[A Cycle of Life]
thickens. He needs the extra
vide little food, and the wolf
warmth for the long winter
hunts daily.
ahead. The male settles for
As the male wolf trots
a meal of lemmings. He
over a ridge, he spies two
weighs nearly 125 pounds
adult wolves and three pups
(57 kg), which is large even
drinking at a nearly frozen
for a male. Lemmings pro-
stream. He approaches with
[A Cycle of Life]
care. Male pack leaders do
hare leaps, zigzags, and scur-
not welcome strange males.
ries to escape. The pup is
Both adult wolves are
too inexperienced to deal
female! They whimper as the
with such active prey. After
male crawls toward them.
fifteen minutes, she returns
The pups belong to the
to her mother and flops
alpha, or dominant, female.
down exhausted.
She and her mate began
In midwinter, the pack
their pack only a year ago.
comes upon a small herd
During the past summer, a
of musk oxen.
caribou’s kick broke her
Working together,
mate’s jaw. He died from the
they single out an
dominant (DOM-uh-nuhnt)
wound. The alpha female
elderly bull. The
leading or head
welcomes a new mate.
bull is already
?
WORDS TO KNOW . . .
The pack roams the
weak from age
tundra looking for prey. Six-
and illness. The
Following the Tundra Wolf
month-old pups are too small
wolves attack.
[ASIN: 6302775418] is a remark-
for pursuing caribou or musk
Wolves use only
able video, worth seeing more
oxen. They begin hunting
their teeth against
than once. It presents a full pic-
lessons with lemmings and
prey. It takes all
ture of the challenges and
snowshoe hares.
their strength and
struggles tundra wolves face in
effort to bring
their daily fight to survive.
A female pup chases a hare through the snow. The Two young wolf cubs dig in the Arctic snow.
WATCH IT!
down the bull. 71
[A Cycle of Life]
Wolves play an important role in keeping musk oxen and caribou herds healthy and strong. The wolves prey only on the sick, elderly, or injured. In that way, healthy herd animals survive to mate and produce healthy young. The musk ox provides a feast for the pack. However, wolves eat in a specific order. The alpha male eats first. His mate eats next. A pup tries to muscle in on the carcass. He gets a warning growl from the alpha male. Wolf parents teach their children good table manners. March arrives. It is
72
May or early June. The mother nurses the litter in the
breeding time for wolves.
den. Her mate and other
Only the alpha male and
pack members hunt for food
female produce young. The
and bring meals to her. The
new pups are born in late
pups are never left alone.
The new pack is secure.
will find mates and
It has three adults, three
teach their pups
juveniles, and four new pups.
to hunt lemmings
juveniles (JOO-vuh-nilez)
Next year, the juveniles will
and hares. That is
young, not yet having reached
be old enough to leave and
the cycle of life for
adulthood
start packs of their own. They
tundra wolves.
A cave between the rocks serves as a den for members of this wolf pack.
?
WORDS TO KNOW . . .
73
8
[Chapter Eight]
The Breeding Season
The Breeding Season 4 Spring comes late to the Arctic tundra. At the end of June, wildflowers sprinkle the land with bursts of color. Insects swarm by the millions. And 15 percent of the world’s bird population
?
WORDS TO KNOW . . .
arrives to breed.
shorebirds (SHOR-burdz) birds
Arctic tundra pro-
that live at the water’s edge,
vides ideal nesting
such as sandpipers, snipes,
grounds for
wildflowers, and clumps of dry
or plovers
waterfowl, shore-
land on which to nest. As sum-
waterfowl (WAW-tur-foul)
birds, and song-
mer approaches, longspurs
swimming birds, such as ducks,
birds. The area
sing their enchanting tunes
geese, or swans
has plenty of
across the open spaces.
lichens, mosses,
Nesting loons, swans, and
74
Snow geese take flight on their way to their Arctic breeding grounds.
TUNDRA SWANS IN THE NEWS Cornell University researchers and scientists from Virginia, Maryland, Pennsylvania, and North Carolina are studying the migration routes of tundra swans. Scientists want to know where the swans breed and what flight paths they travel. They also want to know where tundra swans spend winter months. Scientists captured and marked tundra swans. The swans now wear leg bands, neck collars, and radios. Daily locations of different swans are recorded by the scientists. The study will help scientists preserve tundra swans and other birds that migrate along the same routes. Human
snow geese add their hoots
understanding of how swans live holds
and honks to the chorus.
the key to their survival.
Tiny snow buntings and plovers brave the rugged tundra for the breeding season. Snow buntings raise their 75
[The Breeding Season]
young farther north
More than 180 bird
Golden plovers are excellent
than any other land
species breed in the Arctic.
actors. When a parent plover
bird. They prefer
They arrive for the spring
spots danger approaching, it
rocky, rugged
thaw. Building nests and
draws predators away from the
northern coasts,
laying eggs requires urgent
nest. The plover pretends to
where fewer preda-
attention. Eggs usually hatch
have a broken wing. The preda-
tors will attack their
within three weeks.
tor follows the parent but then
young. Plovers lay
is disappointed. As the predator
their eggs in the
Parent birds gorge their
pounces, the plover flies away.
open. However,
young with insects, worms,
they have excellent
and fish. The young must be
!
WOULD YOU BELIEVE?
Then the race is on.
camouflage. Few predators
able to fly before winter
can spot plovers or their eggs
snows begin to fall. Migration
from the sky.
south may start only three or
A black-browed albatross grooms her young on the Falkland Islands. Albatrosses only come on land when breeding.
four weeks after chicks hatch. Snow geese are regular
arrive in the tundra,
WATCH IT!
the mates quickly
Discover the remarkable Arctic
summer residents of the tun-
build grassy nests.
in Arctic Refuge: A Vanishing
dra. Their black-tipped wings
Female geese
Wilderness (Audubon, 1991).
stand out against snowy white
lay four or five eggs.
This film presents the lives
bodies. They nest in huge
Females sit on the
of tundra animals and the
colonies with as many as
eggs until they are
effect humans have on
200,000 breeding pairs. Snow
hatched in 22 or
wilderness regions.
geese mate for life. When they
23 days. Snow
A lesser golden plover migrates thousands of miles each year to reach its favorite nesting area.
77
[The Breeding Season]
An Arctic tern chick waits with a gaping mouth for dad to bring home dinner.
78
[The Breeding Season]
geese parents take turns pro-
mates dig shallow
tecting and feeding their
holes in the
Arctic terns migrate farther
young. Within a month, the
ground. They line
each year than any other bird.
baby goslings take wing along
the nests with grass
Their annual round trip is about
with the rest of the snow
and leaves. The
21,750 miles (35,000 km).
geese. The goslings must fly
time from egg lay-
several thousand miles to
ing to migration is
their winter homes.
about 45 days.
Arctic terns travel
Many birds of
!
WOULD YOU BELIEVE?
LOOK IT UP! The Arctic has an amazingly large bird population. Learn
yearly from one end of the
prey also breed on
more about Arctic birds at
earth to the other. That’s
the tundra. Arctic
www.mnh.si.edu/arctic/html/
amazing for a bird that
peregrine falcons,
birds.html.
weighs only 4 ounces (113 g).
merlins, jaegers,
They nest and breed in the
rough-legged hawks, and
Arctic in winter, and they
several types of owls nest on
spend summer on islands
grassy mounds. Long-tailed
near Antarctica.
jaegers lead double lives.
Breeding season finds
During the winter, they live
male Arctic terns zigzagging
at sea, but summers find
through the skies to attract
them nesting happily on
mates. Tern nests are not
land.
quite as comfortable as grassy snow goose nests. The
Swans, ducks, and geese find ample food to support 79
A long-tailed jaeger guards its eggs from potential predators. Eggs and chicks are easy prey for weasels, foxes, and wolverines.
80
both parents and chicks. This
not enough food to feed the
is not always true for birds of
baby birds.
prey. Hawks, jaegers, and owls
By late August, migrating
depend on voles and lemmings
birds head south. Some adults
for food. If the lemming popu-
leave their chicks. As soon as
lation is low one summer,
they can, the young birds fol-
these birds may not breed
low their parents south. Flocks
during that season. They
of birds fill the skies in neatly
do not bear young if there is
formed V-shapes. Only a few
Winter approaches. The snow geese form a classic “V” formation as they head south in the early autumn.
[The Breeding Season]
birds, such as the snowy owl
mings are few and winters are
and the gyrfalcon, winter in
harsh, even the snowy owl
the Arctic. Then again, if lem-
heads south for better hunting.
81
9
[Chapter Nine]
The Human Touch
The Human Touch
82
this is no ordinary rain. It does not bring forth delicate white edelweiss or soft pink alpenroses. It does not encourage alpine meadows to grow lush
4 A light spring rain drifts
and green. This rain carries
across the European Alps. But
sulfuric acid and nitric acid.
Coal burning stations like this one pour pollution into the air.
This is acid rain. It burns
factories. Burned fuel pro-
grasses, lichens, mosses, and
duces emissions.
wildflowers of the tundra.
Emissions can be
?
WORDS TO KNOW . . .
smoke or clear
emissions (i-MISH-uhnz) things
burning fossil fuels, such as
gases. Fossil fuel
that are sent off or out, such
oil, gas, or coal. Humans use
emissions contain
as gases
fossil fuels to power cars and
sulfur and nitrogen.
trucks, heat homes, and run
These are basic chemical
Acid raid comes from
What could destroy a pine tree like this? The answer is acid rain, a plague on forests and alpine tundra.
83
This mine at Longyearbyen on Spitbergen Island, Norway, is in the heart of polar bear country.
?
WORDS TO KNOW . . .
atmosphere (AT-muhss-fihr) the layer of gases that sur-
elements found in
atmosphere. When rain falls,
nature.
so does the acid.
When amounts
Acid rain is only one
rounds the earth
of sulfur and nitro-
form of pollution damaging
radioactive (ray-dee-oh-AK-tiv)
gen combine with
alpine and Arctic tundra.
giving off rays from atoms;
elements in the air,
Factories create pollution
high levels of radioactivity kill
they form acid. The
by the bucketful. Chemical
humans, plants, and animals
acids exist with
pollution, air pollution, and
water vapor in our
radioactive pollution take
84
[ T h e H u m a n To u c h ]
their toll on this surprisingly
to affect the tundra
fragile environment.
happened in 1986.
PCBs chemicals called poly-
A nuclear power
chlorinated biphenyls, which
Islands, polar bears face seri-
plant at Chernobyl,
are poisonous to animals and
ous chemical pollution from
Ukraine, in the for-
humans
PCBs. Scientists think that
mer USSR, released
PCBs from European factories
radioactive particles into the
got into river water and even-
air. Wind carried the radioac-
tually into European seas. Fish
tive particles to the Russian
living in water with PCBs
tundra. This is where the
carry the chemicals in their
Saami people live.
In Norway’s Svalbard
bodies. Polar bears eat large
?
WORDS TO KNOW . . .
Saami homeland covers
amounts of fish. The PCBs
parts of Russia, Sweden,
collect in polar bear fat.
Finland, and Norway. The
Scientists believe PCBs may
Saami depend on reindeer for
cause strange changes in polar
food and use their hides for
bear bodies. Eventually, they
clothing and shoes. Radio-
can cause death. During the
activity from Chernobyl poi-
1980s, most nations outlawed
soned the plant life on the
the production of PCBs.
Kola Peninsula in Siberia.
The air carries chemical
Reindeer eating the plants
and radioactive pollution. One
became poisoned. The Saami
of the worst polluting events
people could not risk eating 85
This alpine landscape has been polluted by the radioactive spill at Chernobyl, Russia.
reindeer—even though it was
lution lasts hundreds of years.
their main source of food.
This event has changed the
The government tried to help. However, radioactive pol86
ecosystem for many more years to come.
[ T h e H u m a n To u c h ]
Efforts to
DO IT!
Oil, Gas, and the Arctic Tundra
reseed Prudhoe
Write letters to your U.S. repre-
Bay’s tundra with
sentatives and senators. Ask
4 Humans use oil and gas
plants have failed.
them to keep the Alaska
in huge amounts. Oil and gas
It takes hundreds
National Wildlife Refuge safe
provide power for cars, boats,
of years for lichens
from oil drilling. You’ll find their
and lawn mowers. They fuel
to grow to the size
names and addresses in the gov-
airplanes and trains. They
of a softball. Deli-
ernment section of your tele-
run power plants and facto-
cate tundra plants
phone book.
ries. The need for oil and
cannot rebound
gas makes oil companies
from pollution with-
look in many places for fos-
in only a few years.
sil fuel sources. One such
Oil companies
READ IT! Land of Dark, Land of Light: The Arctic National Wildlife Refuge
place is the North Slope of
now want to drill in
by Karen Pandell (Penguin
Alaska. The drilling spot is
the Alaska National
Books, 1993) takes readers to
Prudhoe Bay.
Wildlife Reserve
one of the last truly wild
(ANWR). The
regions in the world.
Every oil well produces dirty water, sludge, and a dis-
ANWR contains 19
charge called mud. All of that
million acres (7.7 million
gets poured over the tundra.
hectares) of clean, natural
The land cannot absorb the
wilderness. It does not have
huge amounts of muck that
electricity, cars, or garbage.
is dumped there.
ANWR does have 300,000 87
GLOBAL WARMING IN THE NEWS
snow geese that nest there
Global warming is a by-product of rising
each summer. Herds of cari-
earth temperatures over long periods.
bou and musk oxen browse
Car and truck emissions, home and facto-
on Arctic plant life and try to
ry heating, and large cattle farms are
avoid local bears and wolves.
partly to blame for global warming.
Snowy owls and eagles soar
Scientists believe that global warming is changing Arctic ice. Arctic ice sheets
and Arctic ground squirrels
are melting, and shrubs are spreading on
burrow into the shallow soil.
the tundra. Data shows that the area of
This region cannot survive
melting ice has grown by 16 percent in
drilling and the mess that
the past 20 years.
comes with it.
“Shrubs are pushing farther northward, growing in areas of tundra that were void of trees as little as 50 years ago,” says F. Stuart Chapin III of the University of Alaska, Fairbanks.
88
overhead. Lemmings, voles,
One spill at this Colville River ARCO plant could damage the surrounding tundra for decades.
Saving the Tundra 4 Governments realize that tundra environments teem
Asia’s Himalayas, the European Alps, and South America’s Andes Mountains. Beringia International
with life. Several huge national
Heritage Park is a preserve
preserves have been set aside
run by both Russia and the
for tundra regions. In the
United States. The park pro-
Rocky Mountains, Glacier
tects land and marine animals
National Park (United States)
in Alaska and Russia. Musk
and Banff National Park
oxen, caribou, and polar bears
(Canada) are two large pre-
are among the animals roam-
serves. Similar parks exist in
ing the park. 89
[ T h e H u m a n To u c h ]
International efforts to save flagship species have pre-
affects these species. Overhunting of snow leop-
served many Arctic and alpine
ards, vicuñas, and yaks drastical-
species. Canada, Greenland,
ly reduced the numbers of those
Russia, and the United States
animals. Today, governments
worked together to rebuild
provide protected land for these
musk oxen herds. Today, that
species. They keep a sharp look-
species is no longer endan-
out for poachers who kill those
gered in the wild. Several
animals for their skins.
nations protect polar bears
Native tribes work hard
from hunters. By their actions,
to protect species on their
governments are reducing
tribal lands. Wolves and musk
pollution and habitat loss that
oxen benefit from attentive
The U.S. Park Service protects this regal landscape, which is found in Denali National Park, Alaska.
native keepers. Native people
not bounce back
still kill some animals for
from human abuse.
meat and skins. They do so
When polar bears,
subsistence living (suhb-SIS-
for subsistence living. Hunt-
snow leopards, and
tents LIV-ing) humans using
ing for subsistence living is
mountain goats no
local plants and animals in
allowed by law.
longer trek the tun-
order to live; when people rely
dra, the loss will be
on what they are able to pro-
not withstand oil and gas
ours. Extinction is
duce themselves instead of a
drilling, overhunting, or pollu-
a problem with no
cash economy
tion. Tundra ecosystems can-
solution.
Tundra is fragile. It can-
A musk ox grazes on wildflowers in Alaska.
?
WORDS TO KNOW . . .
91
Chart of Species
[ Tu n d r a ]
KEYSTONE SPECIES
FLAGSHIP SPECIES
UMBRELLA SPECIES
INDICATOR SPECIES
AFRICA (MT. KILIMANJARO ONLY)
bees, beetles
lammergeiers, giant lobelias
lammergeiers
lichens, sedges, tussocks, insects
ASIA
pikas, bees, beetles, reindeer, gray wolves
Siberian cranes, marmots, snow leopards, musk oxen
Asiatic black bears, snow leopards, wild yaks, musk oxen
lichens, sedges, tussocks, insects
EUROPE
reindeer, pikas, bees, beetles, gray wolves, chamois, caribou (reindeer), lemmings
polar bears, wolves, chamois, lynx
polar bears, arctic wolves
polar bears, lichens, sedges, tussocks, insects
NORTH AMERICA
caribou, pikas, pocket gophers, bees, beetles, gray wolves, snow geese, lemmings
wolves, polar bears, caribou, grizzly bears, peregrine falcons, musk oxen, Rocky Mountain bighorn sheep
grizzly bears, polar bears, Arctic wolves, Rocky Mountain bighorn sheep
polar bears, lichens, sedges, tussocks, Rocky Mountain bighorn sheep, whitecrowned sparrows, insects
SOUTH AMERICA
bees, beetles
guanacos, vicuñas
guanacos, vicuñas
lichens, sedges, tussocks, insects
CONTINENT
The above chart gives a starting point for identifying key species. Each tundra environment has its own key species. The above chart lists some of those species. Note: Caribou and reindeer are the same species. In North America, the wild species are called caribou. In Europe, they are caribou or reindeer, depending upon the location. In Siberia (Asia), they are called reindeer.
92
[Bold-faced entries are the ones discussed in the text.]