Our Living World: Earth's Biomes - Volume 4: Wetlands

4 volume

Wetlands

T R A D I T I O N A

N E W

Wetlands

OUR LIVING WORLD: EARTH’S BIOMES Barbara A. Somervill

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

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

Barbara A. Somervill is the author

and library market by The Child’s World®

of many books for children. She loves

[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

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.

For The Design Lab: Kathleen Petelinsek, design, art direction, and cartography; Kari Thornborough, page production [PHOTOS] Cover/frontispiece: Paul Edmondson/Corbis. Interior: Animals Animals/Earth Scenes: 26 (Maresa Pryor), 73 (Fred Whitehead), 78 (Michael Fogden), 82 (Peter Weimann), 85 (McDonald Wildlife Photography), 89 (Gordon & Cathy Illg), 90 (Allen Blake Sheldon); Erwin & Peggy Bauer: 37; Corbis: 8 (Richard Cummins), 19 (Galen Rowell), 28 (Mark Jones), 36 (Paul A. Souders), 39 (Peter Johnson), 53 (Kevin Fleming), 64 (Brandon D. Cole), 72 (George D. Lepp), 83 (Gary Braasch), 86 (Bettmann), 88 (Jonathan Blair); Digital Vision: 14; Raymond Gehman/Corbis: 38, 67, 76, 81; Getty Images/ Brand X Pictures: 4, 24, 79; Randall Hyman: 42; Adam Jones/Dembinsky Photo Associates: 11, 51; Wolfgang Kaehler: 48; Dwight R. Kuhn: 41, 54, 69; Frans Lanting/Minden Pictures: 18, 33; Joe McDonald/Corbis: 27, 70; Joe McDonald/Tom Stack & Associates: 65; Barry Mansell/Naturepl.com: 44; Anthony Mercieca/Dembinsky Photo Associates: 61; Minden Pictures: 7 (Tui De Roy), 34 (Tim Fitzharris); David Muench/Corbis: 47, 75; Papilio/Corbis: 55 (Frank Young), 56 (Clive Druett); Photodisc: 10, 20, 21, 22, 30, 58, 62; Marie Read: 77; James P. Rowan: 17; Sydney Catchment Authority: 45, 46; Gerald D. Tang: 12. [ 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



CONTENT ADVISER

Susan Woodward, Professor of Geography, Radford University, Radford, Virginia

4

Table of Contents

Table of Contents [Chapter One]

4 Defining Wetlands [ C h a p t e r Tw o ]

19 Focus on Key Species [Chapter Three]

28 Predators [Chapter Four]

39 Prey [Chapter Five]

45 Flora [Chapter Six]

56 Herbivores [Chapter Seven]

65 A Cycle of Life [Chapter Eight]

73 The Land of Trembling Earth [Chapter Nine]

86 The Human Touch 92

[Chart of Species]

93

[Index]

4

1

[Chapter One]

Defining Wetlands

Defining Wetlands

4

lands every year just before spring. About 75 percent of North America’s sandhill cranes (nearly half a million cranes) gather there for four

4 A flurry of gray and

to six weeks. They come to

beige wings flutter over

stuff themselves on corn

Nebraska’s Platte River wet-

before flying to the Arctic.

[Defining Wetlands]

(3,962 meters). Their 6-foot (1.8-m) wings carry them north to nesting Platte River Wetlands

NORTH AMERICA

Atlantic Ocean

Pacific Ocean

0 0

500 Miles

sites on tundra wet-

?

WORDS TO KNOW . . .

lands. Nebraska

tundra (TUHN-druh) treeless

corn fuels the

areas found in the Arctic or

cranes for the two

on high mountains

500 KM

months of flying it  North America’s Platte River wetlands

Regional farmers harvest their corn crops by machine.

takes to reach the Arctic.

Freshwater Wetlands

Harvesters miss some corn.

4 Wetlands are easy to

Cattle feed on missed ears of

identify. Cover solid land with

corn, but they drop some ker-

1 foot (.3 m) of water, and the

nels. When the cranes arrive

land becomes wetlands. The

each February and March, they

soil becomes sloppy, mucky,

feast on kernels left in the

and squishy. About 6 percent

fields. Farmers estimate that

of all land is covered by wet-

the cranes eat about 1,500

lands. These include swamps

tons of corn yearly.

and bogs, marshes and fens.

The sandhill cranes lift off

The source of water

again in April. They fly at

determines the type of wet-

heights of up to 13,000 feet

lands that develop. Some

 A sandhill crane takes flight above a nature preserve.

5

[Defining Wetlands]

wetlands collect water from rain and snow. ?

WORDS TO KNOW . . .

Amazon River Basin

Some get water

amphibians (am-FIB-ee-uhnz)

from underground

a group of animals that live

springs or rivers.

in both water and on land,

Others collect sur-

including frogs, toads,

face water from

Pacific Ocean

SOUTH AMERICA

Atlantic Ocean

0 0

1000 Miles 1000 KM

and salamanders

runoff or floods.

basin (BAY-suhn) an area

About 94 percent

of land around a river from

of wetlands in the

lichens, mosses, and sedges.

which water drains into

United States hold

Tropical wetlands, such as

the river

freshwater.

much of the Amazon River

 South America’s Amazon River basin

Climate influ-

basin, have warm weather

animals with cold blood, back-

ences the animals

and daily rainfall. Insects,

bones, and, usually, scales or

and plants found in

birds, reptiles, and amphib-

rough skin, including snakes,

wetlands. Arctic

ians live there all year.

lizards, and alligators

tundra wetlands

Grasses and flowering plants

runoff (RUHN-awf) water that

provide nesting

grow over every acre of land

travels over the ground

sites for millions of

all year as well.

sewage (SOO-ij) waste products

migrating birds

carried by water from factories

each summer.

es in nature. They filter pollu-

and homes

Arctic plants are

tion and raw sewage from

mostly low-lying

water. Sometimes a wetland

reptiles (REP-tilez) a group of

6

Wetlands perform servic-

[Defining Wetlands]

environment can clean the water by absorbing pollutants before the water enters our lakes, rivers, and streams. Nature also uses wetlands as a nursery for animal species. Ducks, geese, and more than 100 other kinds of birds breed in wetlands.

Bogs, Pocosins, and Fens 4 Bogs form when sphagnum moss slowly covers a lake or pond from the edge to the center. Bog water comes from the rain or melted snow. As the moss dies, it sinks to the pond floor. The dead moss forms peat because of acidic water conditions and a lack of oxygen. Water gets oxygen from springs, the plant life, and movement such as rapids. Newfoundland, Canada, features  many tundra marshes.

 This peat will be dried and then burned to provide heat for families in County Kerry, Ireland.

!

WOULD YOU BELIEVE?

Peat is cut, dried, and used as

Still water has little

northern Midwest. Bogs sup-

oxygen.

port moose, deer, beavers,

Bogs are found

lynx, otters, and minks.

fuel to heat many homes in

throughout the

Migratory birds, such as sand-

Russia, Germany, and Ireland.

world. In the

hill cranes and short-eared

After a million years, peat

United States, bogs

owls, need bogs for nesting

may slowly turn into coal.

are common in the

sites. The main plant in bogs

northeast and

is sphagnum moss.

8

[Defining Wetlands]

Pocosin is a Native Ameri-

water comes from

!

WOULD YOU BELIEVE?

can term. It is Algonquian for

rain or melted snow.

Sphagnum moss holds many

“hilltop swamp.” The main

Pocosins are found

times its own weight in water.

plants in this swamp are ever-

only along the

Native Americans used the moss

green shrubs. A pocosin’s

Atlantic coast in

for diapers. In World War I, it was used to bandage wounds.

Arctic Ocean

GREENLAND

Arctic Ocean

Arctic 75˚N 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

Pacific Ocean

Pacific Ocean

30˚N

A F R I C A 15˚N

0˚

S O U T H A M E R I C A

Indian Ocean

N

15˚S

AUSTRALIA 30˚S

Wetland Areas 45˚S

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˚

15˚E

30˚E

45˚E

60˚E

75˚E

90˚E

105˚E

120˚E

135˚E

 Wetlands in Africa, Asia, Australia, Europe, North America, and South America

9

150˚E

165˚E

 A black bear cub seeks berries and roots in a bog.

Virginia, the Carolinas, and

Cranes, owls, and sparrows

northern Florida.

make their homes in fens.

Fens are wetlands with a

10

Some fish may live in a

regular freshwater supply.

fen, particularly if a stream

Water levels remain regular in

feeds the wetland. Typical

fens. Quick-growing grasses

fen fish species include

and sedges make many fens

pike, bluegill, bass, and

look like meadows. Large fens

trout. In warm regions,

provide habitats for moose,

snakes, turtles, toads, frogs,

deer, black bears, lynx, hares

and lizards may live in

and rabbits, otters, and minks.

these wetlands. Summer finds this marsh green and healthy. 

[Defining Wetlands]

Freshwater Marshes

marshes. Marshes

?

WORDS TO KNOW . . .

form when rivers or

groundwater (ground-WAW-

4 The term marsh covers a

lakes overrun their

tur) water that exists in bedrock

wide range of very different

banks. Water cover

below the surface of the earth

wetlands. Freshwater marsh-

measures from 6

lands range from hot tropical

inches (15 centimeters) to

river basins to the freezing

about 3 feet (1 m). The water

Arctic tundra.

levels change with the seasons

Rivers, streams, lakes, or groundwater feed freshwater

and weather and are affected by floods or heavy rainfall.

[Defining Wetlands]

 Wet meadows come alive with wildflowers from spring through autumn.

12

[Defining Wetlands]

Cypress and willow trees line the margins between rivers or lakes and the

are mostly grasses and wildflowers. Melting snow and heavy

marshlands. The marshes

spring rains create wet mead-

contain mostly grasses and

ows and prairie potholes. Wet

nonwoody plants. Grasses

meadows are generally grassy

sprout up in the muck. Wild

fields with poor water drain-

irises, orchids, and pale yellow

age. Water sits on the ground,

goldenrod sprinkle marshes

making it soggy.

with color.

Wet Meadows and Prairie Potholes

Prairie potholes form the same way as wet meadows, only they are shallow basins, not flat

?

WORDS TO KNOW . . .

4 Some wetlands last

land. About 10,000

evaporate (i-VAP-uh-rate) to

only as long as it takes

years ago as the Ice

change from a liquid to a gas

for the water they hold to

Age ended, glacial

evaporate. They are seasonal

ice melted, leaving

wetlands and are active usu-

depressions in the

Wetlands: The Web of Life by

ally during winter and spring.

ground. These

Paul Rezendes (Verve Editions,

By summer, the water has

depressions later

1996) presents the stunning

dried up. Temporary wetlands

filled with water,

beauty of swamps, bogs, and

include wet meadows and

becoming potholes

prairie potholes.

some prairie potholes. Plants

or kettles. Many

 READ IT!

13

[Defining Wetlands]

of these holes lie

lands are like truck stops for

Prairie potholes in Canada

in the prairies of

migrating birds. Millions of

and the United States are the

the northern

ducks, geese, cranes, swans,

nesting sites of almost 75 per-

Great Plains in the

and plovers set down for the

cent of the North America’s

United States. The

night in these springtime

migrating waterbirds.

potholes fill with

wetlands. There, they feed

snow and water, cre-

on frogs, toads, and swarms

ating a part-time

of insects. Seed and plant

wetland ecosystem.

eaters feast on the grasses

!

?

WOULD YOU BELIEVE?

WORDS TO KNOW . . .

ecosystem (EE-koh-siss-tuhm) a community of plants and ani-

Seasonal wet-

and wildflowers.

mals and their relationship with the surrounding environment

 White-faced ducks build their nests in wetlands. Their young flourish in a marshy habitat.

14

[Defining Wetlands]

N O R T H A M E R I C A

Southeastern U.S. Swamps

Atlantic Ocean

N

0 0

250 Miles 250 KM

 Southeastern U.S. swamps

Some Freshwater, Some Salt Water

be forests, grasslands, wildflower meadows, ponds, and rivers. Swamps exist on most

4 Swamps and bayous fea-

continents. Water may come

ture more trees and shrubs

from underground springs,

than bogs, fens, or meadows.

rivers, rainfall, or other

Within one swamp, there may

sources. Swamp and bayou 15

PROFILE: CONGO RIVER

water may be fresh, salty, or

SWAMP FORESTS

brackish (part freshwater and

The Congo River supports one of the

part salt water).

largest wet forests in the world.

Swamps support a tremen-

Flooded forests cover a region around

dous variety and quantity of

the river. The Congo swamp forest pro-

life. Plants range from tiny

vides a home to lowland gorillas, chim-

pondweed and duckweed to

panzees, and monkeys. Elephants

soaring bald cypress and

browse on tall grasses and shrubs.

tupelo trees. Wildflowers,

Snakes, frogs, and ever-present insects

herbs, grasses, and ferns grow

abound in this tropical swamp. Rare

by the thousands in swamp

animals living in the region include

environments.

bonobos, red colobus monkeys, and

Swamps are noisy places. Bullfrogs croak, swans trum-

golden-bellied mangabeys.

pet, cranes bugle, and crickets click. The growls of panthers, bears, and alligators mingle with chatter from nesting song-

A F R I C A

birds. Tall reeds and grasses

Congo River Swamp Forests

rattle in the wind.

Atlantic Ocean

Bayous are channels or 0 0

1000 Miles 1000 KM

Indian Ocean

streams of slow-moving water. They connect to swamps and

 Africa’s Congo River swamp forests

16

[Defining Wetlands]

 WATCH IT!

lakes. Only Louisiana, Texas,

water. The roots

and Mississippi have bayous.

form a complex web

Learn about Africa’s most

Snakes and alligators glide

below the water’s

vibrant wetland region. Watch

through algae-filled bayou

surface. This root

National Geographic’s

water. Overhead, drapes of

network supports

Okavango–Africa’s Wild Oasis

Spanish moss hang from

snails, mussels,

[ASIN: 6304839723].

knobby-kneed cypress trees.

crustaceans, and

Saltwater Wetlands

countless numbers

?

WORDS TO KNOW . . .

of fish eggs and

algae (AL-jee) simple, one-

4 Mangrove swamps, deltas,

young. Wading

celled plants

and tidal marshes are nature’s

birds, such as egrets

crustaceans (kruhss-TAY-shuhnz)

fish farms. Many of the fish

animals with hard outside shells,

caught throughout the world

such as crabs

begin life in these waters. Mangrove swamps can be found along tropical or subtropical coastlines, such as those in Florida or Australia. Mangrove trees grow close together, emerging from salty or brackish water. The tree trunk, branches, and leaves form an umbrella over the  Alligators, snakes, and muskrats make their homes in this quiet Louisiana bayou.

17

thousands of seeds. When a delta builds up above the water’s surface, grasses and reeds grow. Wading birds, such as the ibis, nest among the grasses and feed along the water’s edge. The land is often covered with water when tides roll in. Tidal marshes lie close to  A tidal marsh, like this one at Orcas Island, Washington, changes water levels throughout each day.

oceans and seas. Tidal marsh water may be fresh, salty, or

and roseate spoonbills, dip

brackish. Salt marshes form

their bills into the water and

where low-lying land exists

feast on the young hiding

along the coastline. Cordgrass,

among the roots.

glasswort, and sea lavender

Deltas form where rivers

18

sprout in salty marsh soil.

empty into seas. A typical delta

These grasses provide habitats

lies at the mouth of the Nile

for fish and insects to breed.

River in Africa, formed at the

Clams, oysters, crabs, mussels,

edge of the Mediterranean Sea.

and most fish humans eat

Amid the soil dumped by the

depend on tidal marshes for

river to form the delta are

life.

2

[ C h a p t e r Tw o ]

4 At the edge of Florida’s

Focus on Key Species

Focus on Key Species

called a mangrove swamp. The mangrove plant family here consists of trees that are 100 feet (30 m) tall and shrubs that are shorter than 3 feet (1 m). These strange plants thrive in salt water. As high tide approaches,

Everglades, a snarl of trees

salt water rushes through

forms a peculiar ecosystem

the mangrove swamp. The

 Young alligators hide beneath a tangle of mangrove roots.

19

 Beautiful roseate spoonbills use their beaks to scoop food from the marsh muck.

tangled web of mangrove roots

crabs. Slow-moving manatees

provides a safe haven for

munch on sea grass. Mullet

young fish, sea turtles, and

and snapper weave their way through mangrove roots. Roseate spoonbills and herons dip their heads in search of

NORTH AMERICA

shrimp and spiny lobsters. Atlantic Ocean Everglades National Park 0 0

250 Miles 250 KM

Keystone Species 4 A keystone species is any plant or animal that is critical for the survival of other living

 North America’s Everglades National Park

20

[Focus on Key Species]

things within an environment.

birds, manatees, fish, and crus-

Mangrove trees, alliga-

taceans feed among the roots.

tors, and beavers are three

Alligators live in swamps

keystone species in the wet-

from South Carolina through

lands. Each lives in a different

Texas. While they are fierce

ecosystem. Each performs a

predators, they also create

vital role in nature.

habitats for other  LOOK IT UP!

Without the mangrove,

creatures. Alligators

the swamp would not exist.

use their snouts and

Learn more about American

The roots harbor the eggs,

tails to dig “gator

alligators at the U.S. Fish and

larvae, and young of dozens

holes” to live in.

Wildlife Service Web site:

of animal species. Wading

During droughts,

http://species.fws.gov/species_ accounts/bio_alli.html.

 Alligators were once hunted for their skins. Legal protection saved this fierce predator from extinction.

21

alligators rip away tangled water plants. Then sunlight and oxygen are able to reach deeper into the water. Animals living on the swamp bottom get a new chance at life because of alligator landscaping. Beavers create new wetlands. When beavers build dams across streams, they block water flow. A pond forms behind the beaver dam and often overflows the  Long, thin legs allow storks like this one to wade through deep-water marshes and swamps.

nearby land. The new habitat encourages waterbirds to nest

these holes are often the last

in the area. Dragonflies and

areas with water. Insects, frogs,

damselflies lay their eggs

fish, and crustaceans move in

among the reeds. Herons,

beside the alligators. The holes

cranes, and storks arrive

keep other species alive.

to feed on the insect larvae

Alligators also clear chan-

22

and tadpoles. Beaver dams

nels clogged with plant matter.

change dry stream banks into

Using their claws and snouts,

wetland wonderlands.

[Focus on Key Species]

Umbrella Species

Scientists found

?

WORDS TO KNOW . . .

poisonous levels of

endangered (en-DAYN-jurd)

4 An umbrella species is

mercury in the

on the edge of being com-

an animal or plant that spreads

water where otters

pletely wiped out; few members

its legal protection over other

hunt. They fear that

of a species still surviving

creatures. Governments pass

the mercury will

threatened (THRET-uhnd) at risk

laws to protect endangered

kill the otters. If

of becoming endangered

or threatened species.

pollution is regulat-

Hunting, draining water for

ed to protect the otters, those

crops, filling in wetlands for

rules will also help other

building, and pollution put

species living in the Pantanal.

wetland plants and animals at

Animals from jabirus to jaguars

risk. Laws protecting animals

will share the otters’ legal

or plants within these ecosys-

umbrella.

tems protect all creatures that live there. Giant river otters live

SOUTH AMERICA

in the Pantanal, the world’s largest freshwater wetland.

Pacific Ocean

Pantanal

Giant river otters need a

Atlantic Ocean

large hunting territory to catch fish, crustaceans, and

0 0

1000 Miles 1000 KM

small reptiles.  South America’s Pantanal

23

?

WORDS TO KNOW . . .

hammocks (HAM-uhks) raised, dry areas of land within

 Wood storks like plenty of friends around them when they choose a nesting site.

The Florida

a swamp

black bears means restoring

black bear makes its

their environment. Bears share

home on hammocks

their habitats with wood storks,

Black Bear (Our Wild World) by

among cabbage

red-shouldered hawks, armadil-

Kathy Feeney (Creative

palms and scrub

los, raccoons, and wild pigs. A

Publishing, 2000) takes readers

pines. A black bear’s

nature preserve that supports

into the world of the black bear,

range covers from 12

black bears protects these other

a North American species.

to 115 square miles

creatures, too.

 READ IT!

(31 to 298 sq kilome-

24

Birds can also be umbrella

ters). Black bears suffer from

species. Central America’s great

loss of habitat. Humans drain

green macaw eats a variety of

marshland and use the land for

foods. Feeding takes place in

building or farming. Protecting

several different places.

[Focus on Key Species]

Although the macaw’s living

N O R T H A M E R I C A

area is small, its feeding

Atlantic Ocean

area is extensive. Protecting this species would open a Lowland Wet Forests

sheltering umbrella over all

Pacific Ocean

plants and animals of Central America’s lowland wet forests.

0 0

250 Miles

S O U T H A M E R I C A

250 KM

Flagship Species

 Central America’s lowland wet forests

4 A flagship species is an

plants and flytraps.

attention getter. Flagship

Laws protect these

species are usually animals, but

plants from human

carnivorous (kar-NIV-ur-uhss)

can also be plants. Pitcher

collectors.

meat-eating

plants and Venus flytraps, two

?

WORDS TO KNOW . . .

It is easier to  READ IT!

types of carnivorous plants,

get protection for a

attract plenty of attention. In

flagship species

Learn more about plants with a

fact, people try to keep them

than for a less-

bite in Carnivorous Plants by

as houseplants. Pitcher plants

appealing species.

Cynthia Overbeck (Lerner, 1982).

and Venus flytraps are rare.

People would rather

They belong in freshwater bogs

save whooping cranes

and fens, not in people’s living

than winged maple-leaf

rooms. Education made people

mussels. Yet, both species

aware of the threat to pitcher

are endangered. 25

WHOOPERS IN THE NEWS

Whooping cranes have

The year 2002 featured a remarkable

been endangered for years.

event: A pair of whooping cranes raised

So scientists bred whooping

a chick in the Florida wilds for the first

cranes in zoos and protected

time in more than 60 years. The event

compounds. They released

took place beside Dyches Lake. The

breeding pairs of cranes into

whoopers, nicknamed Bonnie and Clyde,

the wild. The whooping crane

were raised at the Patuxent Wildlife

population has now risen to

Research Center in Maryland. They were

about 400 birds. A whooper

released in Florida in January 1999. The

chick born in the wild makes

female laid two eggs in February 2002.

news. When winged mapleleaf

Both chicks hatched, but the smaller one

mussels produce young, hardly

became prey to a bald eagle. The surviv-

anyone notices.

ing chick grew rapidly and took its first flight four months later.

Indicator Species 4 Indicator species report on an environment’s health. When an indicator species thrives, the ecosystem is healthy. If the species dies or moves away, the ecosystem has problems. Insects make excellent indicator species. Dragonflies,

 This delicate damselfly tells scientists whether a marsh or bog is healthy simply by showing up and laying her eggs.

damselflies, and caddis flies

shows scientists that the water

buzz around wetlands, feeding

quality is good and

on other insects. A freshwater

that plant quantity is

wetland without one or more of

high. Mussels are

microscopic (mye-kruh-SKOP-ik)

these insects is a sick wetland.

filter feeders. To eat,

too small to be seen with the

they filter food and

naked eye; only seen with the

as indicator species in many

water through their

help of a microscope

wetlands, including mangrove

bodies. When there

swamps. Snails eat algae and

is too much pollution, the mus-

other microscopic wetland

sels cannot filter properly, and

plants. When pollution is too

mussel colonies die off. If the

great, algae will not grow.

water is healthy and food is

Often a large snail population

plentiful, mussel colonies grow.

Snails and mussels serve

?

WORDS TO KNOW . . .

27

3

[Chapter Three]

Predators

Predators

28

up to 1,000 insects in an hour. Long-nosed bats sweep through the darkness. A series

4 At dusk, bats leave their

of sharp chirps echoes over

roost to hunt their favorite

the still waters of South

prey—insects. One bat may eat

America’s Pantanal. The

[Predators]

bats use echolocation to find swarms of insects.

SOUTH AMERICA

About 140 types of bats live in the Amazon and

Pacific Ocean

Pantanal

Pantanal wetlands. This is

Atlantic Ocean

about 25 percent of the mammal species living in the

0

1000 Miles

0

1000 KM

region. The region supports vampire bats that drink blood

 South America’s Pantanal

from animals for food. The

eating insects to

most fascinating bat, however,

birds, reptiles, and

carnivores (KAR-nuh-vorz)

is the greater fishing bat,

mammals. The num-

animals that eat meat

which scoops fish from the

ber and variety of

echolocation (EK-oh-loh-kay-

water with its hind legs, just

predators depend on

shuhn) the process of finding

like an eagle. One major dif-

the availability

an object by bouncing sound

ference between fishing bats

of prey. Predators

off it to determine its size and

and fishing birds is that the

can be carnivores

distance; used by bats, whales,

bats hang upside down to

or omnivores.

and dolphins

enjoy their feast.

Food Supply

Mammals are

?

WORDS TO KNOW . . .

omnivores (OM-nuh-vorz)

the largest wetland

animals that eat both plants

predators by size,

and meat

4 Wetland predators range

but not by number.

from fierce spiders and meat-

Foxes, lynx, panthers, jaguars,

 More than 140 different types of bats thrive in South America’s Pantanal.

29

wetland animal group. Many insects are carnivores. Mosquitoes and certain fly species are particular predators. They drink blood for food. Their victims are several times larger than they are and do not die from the bites. Dragonflies, damselflies, and mantises are active wetland predators. The larvae of dragonflies and  Clever raccoons can open coolers and garbage cans. They scavenge for food with ease.

damselflies live in ponds or standing water. They

?

raccoons, and otters are mam-

feed on fish, insect eggs,

mal hunters in the wetlands.

and tadpoles. Their parents

Some predators eat only live

hover over ponds to catch

WORDS TO KNOW . . .

carrion (CAH-ree-uhn) dead or rotting flesh

animals or freshly

flying insects. Mantises

killed meat. Others

appear to say grace over

feed on carrion.

their meals. They hold their

Insects outnumber every other

30

food before them and bow their heads to feed.

[Predators]

Spiders spin elegant webs

PROFILE: COTO DOÑANA

among tall wetland grasses.

Spain’s Coto Doñana National Park

The spiny-bellied orb weaver

is a bird sanctuary and a freshwater

spider weaves a sticky web to

refuge for many wetland animals. Two

catch flying insects. The spider

endangered predators live in the park:

bites its victims and delivers a

the Spanish lynx and the Spanish impe-

paralyzing poison.

rial eagle. There may be only about

Wolf spiders do not spin

1,000 Spanish lynx left in the world.

sticky webs. They hunt their

The park supports about 50. Spanish

food. Wolf spider coloring

imperial eagles feed on rabbits living

blends in with their sur-

in Coto Doñana. Only 100 to 150

roundings. They lie in wait

breeding pairs of Spanish imperial

for insects to wander past,

eagles survive in the wild today.

and then they pounce. Wolf spiders live on every continent except Antarctica.

Atlantic Ocean

Birds on the Hunt E

U

R

O

P

E

4 Meat-eating birds eat everything from insects to fish to slippery water snakes.

Coto Doñana National Park

0 0

500 Miles 500 KM

Songbirds, such as vireos and swallows, eat insects by the

 Europe’s Coto Doñana National Park

31

[Predators]

thousands. Whippoorwills pre-

have long legs. Their legs let

fer moths, which they catch in

them walk through shallow

midflight. Major wetland bird

water to find food.

predators, however, are usually

The shape of a wading

birds of prey or wading birds.

bird’s bill suits the type of food

The most aggressive

the bird eats. Bills can be

hunters are birds of prey, such

spoon-shaped, straight, or

as harriers, eagles, and hawks.

curved. The roseate spoonbill

Europe’s marsh harriers are

scoops up small fish, insects,

opportunistic feeders. They

and small crustaceans. Most

take advantage of whatever

herons, egrets, and cranes have

opportunities arise to eat. If

straight, sharp bills. They peck

frogs are available, they eat

at fish, frogs, lizards, and

frogs. When mice

snakes hiding among water

or ducks come

plants. Curlews have narrow,

Wading birds and waterbirds

around, they also

curved beaks. They step care-

devour many of the Everglades’

make tasty meals.

fully in the shallows and use

insects, worms, frogs, and snails.

Wetlands sup-

 WATCH IT!

their bills to pluck worms from wetland mud.

Learn about how they hunt in

port wading bird

the Education 2000 video Birds

species, such as

of the Everglades [ASIN:

cranes, egrets,

B00000IQH3].

herons, and storks.

4 Reptiles such as snakes,

Wading birds usually

snapping turtles, alligators,

32

Scaly Hunters

A marsh hawk makes a meal of a snow goose. This may seem cruel, but it is all  part of nature’s plan.

[Predators]

and crocodiles are successful

warm. Many reptiles enter the

wetland hunters. Reptiles are

water only to hunt.

cold-blooded and cannot gen-

Water snakes are generally

erate body heat on their own.

harmless to humans and are

They sun themselves to keep

essential to nature. They feed

!

WOULD YOU BELIEVE?

The marabou stork is one of Africa’s largest birds. It has a

 Marabou storks in Kenya feed on the carcasses of dead flamingos. They are wetland garbage collectors.

wingspan of 10 feet (3 m).

on rodents, such

Although it is a wading bird,

as water shrews,

ground snakes. They feed

the marabou stork eats like a

voles, and swamp

on mice, rats, shrews, and

vulture or buzzard. It prefers

rats. Only one

voles, as well as frogs, toads,

carrion. Only when they are

North American

and lizards. Many ground

very hungry will marabou

water snake—the

snakes found in wetlands

storks wade in the water to

cottonmouth, or

are poisonous. These include

catch live frogs and snakes.

water moccasin—

rattlesnakes, copperheads,

is poisonous.

coral snakes, and vipers.

34

Wetlands also attract

[Predators]

One of the deadliest snakes,

PROFILE: INDIAN GHARIAL

South America’s ferdelance,

Indian gharials, relatives of crocodiles,

slithers through wet forests in

are a threatened species. They live in

the Amazon.

wetlands along the Ganges, Indus, and

Wetland turtles tend to

Brahmaputra

be omnivores. Snapping turtles

rivers. In the

prefer fish, but they will hunt

1970s, gharials

extinction (ek-STINGKT-shuhn)

water snakes and baby alliga-

teetered on

the state of having no more

tors. Some turtles, such as the

extinction. They

living members of a species

peninsula cooter, eat meat

were hunted for

when they’re young and eat

their skins and meat.

plants as adults.

?

WORDS TO KNOW . . .

Female gharials normally lay 30 to

Alligators and crocodiles are the largest and fiercest

50 eggs. Only two or three babies from one litter reach adulthood in the wild. To save the gharial from extinction, scientists collected eggs from their nests.

Aral Sea Caspian Sea

A

S

I

A

They raised young gharials on ranches.

us R iv

er

Ind

They improved the success of a litter

Arabian Sea

Indian Ocean 0 0

Br

Ga n

a h m aputra Ri v er

from 2 or 3 adults to 30 or 40. ges R

i v er

Scientists released more than 3,000 Andaman Sea

500 Miles

gharials in Asian wetlands. Today, several thousand gharials live in the wild.

500 KM

 Asia’s Brahmaputra, Ganges, and Indus rivers

35

[Predators]

reptile predators. Most continents have at least one type

Cats on the Prowl

of crocodile or alligator. The

4 Big cats, such as jaguars

most dangerous crocodile is

and panthers, thrive in wet-

the Nile crocodile of Africa.

lands. Although many cats

These fearsome crocodiles

dislike water, jaguars are

kill more humans each year

excellent swimmers. When

than lions or tigers.

the Amazon rain forest

 Nile crocodiles are keystone species throughout African wetlands.

36

[Predators]

floods, jaguars take to the water to hunt. Florida panthers are endangered in the wild. They live on hammocks in Florida swamps. Florida panthers feed on deer, hogs, raccoons, and armadillos. Fewer than 50 Florida panthers live in the wild. Bobcats, midsized wildcats, hunt in marshes, bogs, and swamps. They feed on rodents and ground birds. Bobcats hunt at night and, like jaguars, will swim for their supper if necessary.

Successful Predators 4 Predators that eat a variety of different foods fare better than picky eaters. The apple snail kite may soon become extinct. One of the reasons for A Florida panther stalks its prey deep  in the Everglades National Park.

 Apple snail kites face extinction because they limit their diet to one particular type of snail.

this bird’s decreasing num-

them to eat. Insects breed

bers is that it eats only one

by the millions in wetland

type of snail. When that snail

environments. That is why

population drops, the kites

so many insectivores live

starve. Compare that to black

in wetlands.

bears that will eat berries, nuts, seeds, honey, insects, fish, and carrion. ?

WORDS TO KNOW . . .

The variety of

Predators fulfill an important role in nature. Without predators, insects would take over wetlands. Predators also

insectivores (in-SEKT-uh-vorz)

predators in an area

do garbage duty by eating car-

animals that eat insects

depends on the

rion. They maintain a com-

prey available for

fortable balance in nature.

38

4

[Chapter Four]

Prey

Prey

curved horns, the antelope would rather flee than fight. Swamp antelopes, or sitatun-

4 A lion stalks a 220-pound

gas, head for deep water when

(100-kilogram) swamp antelope

they are in trouble. They are as

through the Okavango Delta.

comfortable in water as they

The antelope senses the dan-

are on land. This time, the

ger. Although he has sharp,

antelope escapes the lion but

 When this young sitatunga reaches adulthood, it will face dangers from lions on land and from crocodiles in the water.

39

[Prey]

antelopes, growing up to 4 inches (10 cm). The hooves’ shape allows sitatungas to

A F R I C A

walk over soggy ground. As prey, swamp antelopes are

Atlantic Ocean

0 0

1000 Miles

caught between fierce lions of Okavango Delta

Indian Ocean

1000 KM

the grasslands and powerful crocodiles in the swamp.

 Africa’s Okavango Delta

runs into a more fearsome predator—the Nile crocodile. Sitatungas live in African

A Well-Stocked Market 4 Predators have no trouble finding a decent meal in wet-

wetlands. They have

land ecosystems. Prey can be

adapted to swamp

bigger than the swamp ante-

nutrients (NOO-tree-uhnts)

life. Swamp ante-

lope or smaller than the eye

substances needed by plants,

lopes feed mainly

can see. Regardless of size,

animals, or humans for growth;

on reeds and

prey provides needed protein

key elements of food

papyrus, which

and nutrients for predators.

papyrus (puh-PYE-ruhss) a tall

grow in freshwater

grass that was used to

marshes. Their

plankton. These microscopic

make paper in ancient Egypt

hooves are much

animals drift in water. Zoo-

and Greece

longer than the

plankton can be fish or frog

hooves of other

eggs, insect larvae, or tiny

?

WORDS TO KNOW . . .

40

The smallest prey is zoo-

 Wood frog tadpoles hide in the safety of marsh grasses.

shrimplike animals. Water

Mosquitoes, midges, flies, and

insects, beetles, fish, birds, and

caddis flies breed by the mil-

reptiles feed on zooplankton.

lions in wetlands. Huge popula-

Zooplankton live in freshwater,

tions are necessary because

salt water, and brackish water.

predators can eat more than

Insects make excellent

1,000 insects in one feeding.

prey as eggs, larvae, and

Frogs are food for preda-

adults. Bats and birds are

tors as eggs, tadpoles, and

insect eaters, along with fish,

adults. For a meal, an otter

frogs, and small mammals.

might eat one thousand frog

Some insects, such as dragon-

eggs, ten tadpoles, or one adult

flies, can eat their weight in

frog. Female frogs lay thou-

other insects every day.

sands of eggs each spring. The 41

[Prey]

 LOOK IT UP!

eggs quickly hatch

water animals. Wetland mam-

Learn about the frogs and toads

into tadpoles. The

mals dig up reptile nests and

that live in Florida’s Corkscrew

growth from tadpole

eat the eggs—if they get the

Swamp. Visit the swamp’s Web

to frog takes about

chance. Female crocodiles and

site at http://www.audubon.org/

12 weeks. Luckily,

alligators guard their nests

local/sanctuary/corkscrew.

very few eggs sur-

closely. Turtles do not.

vive to adulthood,

When hatchlings emerge

or every wetland environment

from nests, they are in danger.

would croak from a huge frog

Wading birds, snakes, and fish

population.

wait anxiously to feast on the

Some animals are prey as

young. Oddly, the same ani-

eggs or young but have few ene-

mals that prey on hatchlings

mies as adults. Alligator, croco-

might be eaten by the young-

dile, and snapping turtle hatch-

ster’s adult relatives.

lings fall prey to both land and

Among mammals, rodents

[Prey]

provide food for many larger

enemies. Praying mantises

creatures. Water snakes keep

are leaf green in color. Birds

mouse, rat, vole, and shrew

that feed on mantises cannot

populations under control in

always see them against

most wetland ecosystems.

green reeds. Bitterns and

Voles and shrews produce

curlews that live in European

several litters of young each

marshes have feathers colored

season. They reproduce

like marsh reeds. A nesting

quickly to keep population

bittern is impossible to see

numbers steady.

unless it moves.

Size does not keep prey

When hiding doesn’t

safe from predators. South

work, it’s good to run away.

American anacondas often

Most frogs and toads can hop

catch capybaras, the world’s

a good distance when fright-

largest rodents, when they

ened. With luck, they hop out

drink at the water’s edge.

of the reach of their predators.

Feeding or drinking water leaves victims open to attack.

Good Defenses

Freshwater mussels and snails survive because of their

?

WORDS TO KNOW . . .

hard shells. The

camouflage (KAM-uh-flahzh)

4 Prey have a few defenses

shells protect them

coloring that blends in with

against predators. Camouflage

from many possible

the surroundings

helps hide prey from their

predators, but not

 An alligator mother protects her young. Few of her hatchlings will survive to become adults.

43

wetland animal feeds others. Prey may be the eggs, infants, or adults of a species. It can also be the carrion left when animals die. Nature does not waste good food. If food is available, some animal will gnaw, suck, or chomp it. This is true in both freshwater and saltwater environments. The food cycle depends  This round-tailed muskrat keeps a wary eye out for owls and hawks while munching on a meal of marsh reeds.

on prey and predators. Without predators, prey

all of them. Muskrats, rac-

would reproduce in massive

coons, and herons have no

numbers. Prey populations

trouble cracking shells to eat

would soon take over

the meat inside.

swamps, wet meadows,

Today’s Predator, Tomorrow’s Dinner 4 Alive or dead, every 44

fens, and bogs. Predators keep prey population levels in check. This is another example of nature’s balance.

5

[Chapter Five]

Flora

Flora

time, it collected peat and runoff water. Peat filtered the water until it was pure.

4 Formed by glaciers

The Australians valued the

thousands of years ago, the

peat fen as a wetland and as

Wingecarribee basin in the

a freshwater reservoir.

mountains of southeast Australia is a peat fen. Over

?

WORDS TO KNOW . . .

reservoir (REZ-ur-vor) a place for storing water

 Wingecarribee was once an active, productive wetland environment.

45

A machine that cuts peat, called a dredge, lay anchored in the fen’s center next to the reservoir. The dredge’s platform stood on legs running down into the peat. A buffer zone separated the digging operation from the reservoir. The buffer zone was a natural dam made of thick peat and soil. In August 1998, heavy rains flooded the fen. The  When the dredge cut through the swamp, it destroyed thousands of years of ecological development.

dredge slipped from its anchor. Water and peat pushed the dredge through the buffer

Indian Ocean

zone, carving a channel through the earth. Because it A U S T R A L I A

ran on gasoline, the dredge Wingecarribee Wetland

Indian Ocean 0 0

500 Miles

carried pollutants. As water emptied from the wetland into the reservoir, those pollutants

500 KM

entered the pure drinking  Australia’s Wingecarribee wetland

46

[Flora]

water system. An ecosystem that had existed for thou-

Freshwater Wetland Plants

sands of years was destroyed

4 Plants play a vital role in

in a matter of hours.

establishing a healthy environ-

 Ferns make up a large portion of the plant life in Akalai Swamp, a tropical wetland located in Hawaii.

47

growing seasons. The plant life can grow so thick that humans can barely cut their way through it. Temperate wetlands support plants that survive freezing winters and bloom in hot summers. Tundra wetlands teem with plants that hug the ground to protect themselves from the constantly cold temperatures. Wetlands may have water only part of the year. Prairie potholes are seasonal ecosys Papyrus, a woody grass, has been used as paper and lashed into rafts or boats. Papyrus provides a safe haven for marsh young.

tems where plants grow until the water disappears. Other

ment. The amount

wetlands, such as swamps and

biomes (BYE-ohmz) large

and variety of plant

fens, are always underwater.

ecosystems in which the

life in a wetland

Cattails, bulrushes, and

plants and animals are adapted

ecosystem depends

papyrus roots and stems are

to a particular climate or

on the climate.

always covered with water.

physical environment

Tropical wetlands

?

WORDS TO KNOW . . .

have year-round 48

Wetland biomes have three types of plants: emer-

[Flora]

gent, submergent, and free-

marshfinger grass.

floating. Emergent plant roots

They can also be

Wetland wildflowers can have

and lower stems lie under-

thick and woody,

strange names. Green adder’s

water. Their branches, upper

such as papyrus or

mouth looks like an open

stems, and leaves live above

bamboo. Cane, bul-

snake’s mouth. Pussy toes are

water. Submergent plants live

rushes, and reeds

soft and furry. Beard tongue

completely underwater. They

grow in freshwater

is a furry, tongue-shaped flower.

may send shoots above water

wetlands. Salt grass,

Beggar-ticks, Dutchman’s-

to produce seeds. Free-

spike grass, and

breeches, green dragon, and

floating plants are plants

cordgrass thrive in

lizard’s tail also decorate North

with no fixed roots. They

salt water or tidal

American wetlands.

float on the water’s surface.

marshes.

Emergent Wetland Plants

!

WOULD YOU BELIEVE?

Not every bit of wetland soil is under inches of water.

4 Emergent plants grow in

Some soil may just be spongy

every type of wetland. Most

and damp. Typically, ferns

plants in temporary wetlands,

grow in this spongy, moist

such as prairie potholes, are

soil. They do not produce

emergent plants. Emergent

flowers or seeds, but instead

plants include grasses, ferns,

they reproduce by spores.

wildflowers, and trees.

Ferns can be tiny and look

Emergent grasses can be thin, green stalks, such as

like moss. Or they can grow as tall as trees. Tree ferns 49

PROFILE: HERBS OF THE WETLANDS

grow in Australia and South

Native Americans often used wetland

America. Common wetland

herbs to cure sickness or fix wounds.

ferns include adder’s-tongue

They made herbal remedies to stop

and maidenhair fern.

bleeding, treat burns, ease headaches, or

!

Hundreds of wildflowers

take the itch out of bites. They crushed

paint wetlands with brilliant

leaves and bark and soaked them in hot

colors. Blue flag or yellow

water to make healing tea. Knowledge-

flag irises, Queen Anne’s

able medicine men and women ground

lace, and pink marshmallow

dried leaves with bear or duck grease to

dance in soft summer winds.

make ointments. Native herbalists knew

Cattails bob up and down at

how to use everything from Spanish

the water’s edge. Daisies,

WOULD YOU BELIEVE?

When in a wetland ecosystem, remember the rhyme, “Leaves of three, beware of me.” Avoid

moss to skunk

goldenrod, dandelions, and

cabbage to cure

buttercups sprinkle yellow

health problems.

amid the rich greens of wet meadows. Knobby-kneed bald

plants with clusters of three

cypress trees fare well in

leaves on a stem. You may be

freshwater swamps. Willows

touching poison ivy, poison oak,

and alders edge freshwater

or poison sumac. All three give

marshes. Evergreens such as

humans itchy rashes.

magnolias, hollies, cedars, and pines grow well in wetland

50

Spanish moss hangs from a bald  cypress tree in a Louisiana swamp.

[Flora]

environments of the south-

the water’s surface. Some sub-

eastern United States.

mergent plants send shoots

Freshwater Submergent Plants 4 Submergent plants live

above the water level when it is time to produce flowers and seeds. Freshwater submergent

underwater. Their roots, stems,

plants include bladderwort,

and leaves produce food under

water milfoil, and hydrilla.

[Flora]

Bladderworts eat

quickly and chokes off the

Some plants are both male

meat—or rather,

growth of native water plants.

and female. Coontail is a free-

they dissolve insects.

Within a short time, milfoil fills

floating submergent plant

When water insects

a pond completely, blocking

that bears both male and

or larvae touch the

sun from other plants and mak-

female flowers. When it

hairs around the

ing water travel impossible. The

is time to reproduce, the

plant’s bladders,

plant cover kills other native

stamens release from the male

the plant sucks the

plants, fish, and animals within

flowers. The stamens

prey inside. The

the pond. Animals and insects

rise to the surface and open.

bladderwort takes

that depend on pond life suffer

Their pollen fertilizes the

needed nutrients

from loss of habitat. Because

female flowers. Seeds form

from its prey.

milfoil has no natural enemies

!

WOULD YOU BELIEVE?

and are carried by the water.

Alien or non-

in North America, it is difficult

New colonies of coontail

native water plants

to control once it begins grow-

begin without the parent

create serious prob-

ing in wetland areas.

plant ever breaking the

lems in wetlands.

water’s surface.

Two such North

freshwater aquarium plant.

American exotics,

The plant entered North

or aliens, are milfoil

American wetlands when peo-

stamens (STAY-muhnz) the

and hydrilla. Milfoil

ple washed out their aquari-

pollen-producing parts of

comes from Europe,

ums. Hydrilla passed through

a flower

Asia, and northern

the sewer systems and into

Africa. Milfoil grows

wetlands. Like milfoil, hydrilla

?

WORDS TO KNOW . . .

52

Hydrilla is a common

A dredge scoops hydrilla and water lilies from Lake Okechobee, Florida. The weeds  clog the lake and kill other plant life.

[Flora]

took over. Some scientists sug-

attached roots. They include

gest introducing grass carp to

duckweed, pondweed, water

eat hydrilla. The important

hyacinth, and mos-

question is, what will eat the

quito fern. Floating

grass carp when it starts to

plants live in all

phytoplankton (fie-toe-

grow out of control?

types of water. They

PLANGK-tuhn) one-celled

are found through-

floating water plants, such as

out the world.

algae or diatoms

Floating Plants 4 Floating plants have no

Phytoplankton, the

?

WORDS TO KNOW . . .

 Freshwater snails like the one shown here feed on phytoplankton.

 WATCH IT!

smallest water

in all wetlands. Zooplankton,

Discover the animals living

plants, live in both

snails, mussels, and clams

among the roots of swamp

freshwater and salt

feed on phytoplankton. Every

trees. Watch National

water.

larger animal that lives in a

Geographic’s Creatures of the Mangrove [ASIN: 6304474571].

54

Phytoplankton

wetland ecosystem eats food

forms the founda-

that can be traced back to

tion for food webs

phytoplankton.

[Flora]

Saltwater Wetland Plants

PROFILE: MOSQUITO FERN Mosquito fern drifts in freshwater ponds, lakes, and wetlands of North

4 Tidal wetlands have

America. Like duckweed and algae,

changes in water level

mosquito fern forms a living blanket

twice daily. The tide comes

over still freshwater. In autumn, the

in and out roughly every

fern changes from brownish green to

12 hours. A mangrove

deep rust red. In winter, mosquito fern

swamp flourishes under

lies inactive on the wetlands’ floor. In

in-again-out-again water.

spring, ferns rise to the surface. They

The regular flow of new salt

produce a new crop of mosquito fern

water helps to cleanse the

to spread over the water.

swamp. Coastal wetlands support several grasses, such as eelgrass, redhead, and wigeon grass. Not true grasses, these plants belong to different families. Saltwater grasses provide habitats for small fish and crabs, insect larvae, and fish eggs. They feed ducks, geese, and swans.

6

[Chapter Six]

Herbivores

Herbivores

56

other types of deer produce only one or two fawns per year. The doe hides her fawns

4 A Chinese water deer

among the marsh reeds. The

doe delivers four fawns in late

fawns’ brown-and-white coats

spring. Water deer can have a

blend in perfectly. They are

litter of up to six fawns. Most

invisible to predators.

[Herbivores]

lands of England and France. The English-based Chinese water deer herds were created A

S

I

A

Water Deer Habitat

0 0

1000 Miles

when captured deer escaped from wildlife parks.

Large Plant Eaters

1000 KM

4 Deer of all types are  Water deer habitat in eastern Asia

Chinese water deer are

among the largest herbivores in wet-

?

WORDS TO KNOW . . .

herbivores. Although they

land environments.

herbivores (HUR-buh-vorz)

generally feed on reeds, grass-

North America’s

animals that eat plants

es, and leaves, they also eat

white-tailed deer

crops. Rice paddies, wheat

live in forests,

fields, and even carrot patch-

grasslands, swamps,

Chinese water deer have no

es are not safe from hungry

wet meadows,

antlers, but they do have tusks.

water deer. Chinese farmers

and fens. They

Males grow tusks about 2 inches

think the deer are pests.

feed on grasses,

(5 cm) long. Female tusks are

Water deer live in

leaves, and, in

much smaller. The tusks are

swamps, stands of marsh

times of great

used as weapons when males

reeds, and grasslands of north-

hunger, tree bark.

fight for the right to mate with

ern China and Korea. The deer now also live in the wet-

Other large

!

WOULD YOU BELIEVE?

a doe.

wetland herbivores

 Chinese water deer make pests out of themselves by eating farmers’ crops.

57

PROFILE: BAMBI GONE BERSERK In the 1700s, southern U.S. coastal colonists hunted white-tailed deer nearly to extinction. Limited deer hunting became law. This was the first attempt in North America to save an endangered species. Then, humans made a big mistake. Throughout the South, humans killed off the major deer predators. Without wolves or cougars, the white-tailed deer population exploded. In coastal wetlands and swamps, deer have become a plague. They actually eat away the balance nature provides

 Moose are among the largest plant eaters in the wetlands.

between plants and animals. Hunting

include moose, elk, and

cannot reduce the deer numbers

Chincoteague ponies. These

sufficiently. Only natural predators—

herbivores graze on grasses,

and plenty of them—can get the

reeds, and tender leaves.

situation under control.

Moose wade into lakes and rivers to browse. Chincoteague ponies are wild. They are the distant relatives of tame ponies

58

[Herbivores]

PROFILE: FRANCE’S CAMARGUE REGIONAL NATURE PARK

Atlantic Ocean

Southern France boasts a stunning, E

U

R

O

P

E

Camargue Regional Nature Park

vital wetland environment called the Camargue. The Camargue is a delta wetland that was formed where the

0 0

500 Miles

Rhone River empties into the

500 KM

Mediterranean Sea. About 12,000  Europe’s Camargue Regional Nature Park

greater flamingos arrive each year to breed in the Camargue. The females

that were released or escaped

build mud mounds on islands in the

several hundred years ago.

park. The birds lay only one egg. When

In Asia, water buffaloes

they lift off in flight, they fill the sky

wallow in wetland mud.

with shades of pink and coral. The

They feed on reeds, bulrushes,

flamingos share their winter retreat

and water grasses. Water buf-

with thousands of mallards, widgeons,

faloes rarely move far from

and shovelers. Nutria, grass snakes, and

these areas.

viperine snakes live on land where

Malaysia’s bearded pigs

French farmers plant rice. Much of this

don’t bother picking fruit for

vast wetland has been turned into rice

themselves. They follow mon-

fields or cattle pastures.

keys through the mangrove swamps. The monkeys drop 59

[Herbivores]

in its Congo River swamp forest home. A

S

I

Hummingbirds dart

A

among wetland wildflowers, feasting on the flowers’ sweet nectar. Several kinds of bats MALAYSIA 0 0

1000 Miles 1000 KM

eat only fruit or nectar. Swamp rats like seeds and

 Malaysia in southeast Asia

berries along with their

partially eaten fruit, which

normal meal of stems and

becomes a quick meal for

leaves. Meadow voles can be

Malaysia’s bearded pigs.

found hunting for seeds and

Herbivores do not just graze on grass and leaves. They also eat the fruits of

roots in most wet meadows and prairie potholes. Many wetland birds

plants: berries,

feed on seeds, berries, and

seeds, nuts, and

insects. Cardinals, goldfinch-

Step into the swamp! Read

nectar. The Ama-

es, and pine siskins mainly

Theresa Greenaway’s Swamp

zon’s hoatzin bird

eat seeds. They all eat

Life (Dorling Kindersley, 1993)

feeds on fruit and

insects, too. Indigo bunt-

and get a close-up view of the

flowers. Africa’s

ings dine mainly on insects

swamp ecosystem.

red colobus monkey

but peck seeds and berries

eats fruit and leaves

off the ground.

 READ IT!

60

[Herbivores]

Most people recognize

PROFILE: RUBY-THROATED

beavers, squirrels, and rabbits.

HUMMINGBIRD

Beavers create wetland ecosys-

The ruby-throated hummingbird feeds

tems and feed there as well.

on the nectar of flowers in woods, gar-

They eat leaves and tender

dens, swamps, and wet meadows. These

branches, along with river

tiny hummingbirds weigh only about

reeds. Gray squirrels can live

1 ounce (28 grams) but migrate nearly

anywhere trees grow. They

2,000 miles (3,200 km) each year. Ruby-

thrive in swamps where

throated hummingbirds eat twice their

nuts, berries, fruit, and seeds

weight in nectar each day, mostly from

are plentiful. Cottontail and

red flowers.

[Herbivores]

 Northern shoveler ducks migrate to the North American tundra from the south each spring. The Migratory Bird Act of 1918 protects them on their journey.

62

[Herbivores]

marsh rabbits nibble their

eat more berries, roots, nuts,

way through grass and wild-

and leaves. Bears in a feeding

flowers. Clover is a favorite

frenzy can eat 200,000

food of rabbits.

berries in only one day.

Swans, geese, and many ducks eat water plants, seeds,

Saltwater Plant Feeders

and roots. Baby swans, called

4 Some animals living

cygnets, feed on worms and

among the man-

insect larvae as infants, but

grove roots and salt

they eat mostly plants as

marsh grasses are

detritus (deh-TRY-tuhs) dead

adults.

detrivores or herbi-

plant or animal material or

vores. Dead man-

organic waste

grove leaves and

detrivores (deh-TRY-vorz)

4 Although many omni-

branches fall into

animals that eat dead or

vores are considered preda-

the salt water of the

rotting matter

tors, some prefer plants.

swamp. This dead

Surprisingly, many bears eat

matter is called detritus.

far more plant matter than

Detritus is the foundation for

meat. More than 75 percent

the food web within the

of the black bear’s diet con-

swamp. Snails, shrimp, and

sists of fruit, nuts, seeds, and

crabs that eat the detritus

honey. Grizzly bears, known

grow and become food for

for eating salmon, actually

larger fish, crabs, and birds.

Omnivores

?

WORDS TO KNOW . . .

63

 Fierce-looking fiddler crabs spend their days dining on scraps of seaweed.

Butterflies and beetles feed on the live leaves and

their big claws, they look

bark. They are food for a

fierce and threatening.

host of birds and spiders

However, these scuttling

living among the mangroves.

crustaceans actually thrive

Fiddler crabs may be the most interesting of the tidal 64

salt marsh herbivores. With

on bits of seaweed and algae caught among marsh grasses.

7

[Chapter Seven]

4 Night has fallen, and a snake is on the hunt. The

A Cycle of Life

A Cycle of Life

snake skims through a Louisiana bayou with its head raised above the water. It is a cottonmouth—a deadly poisonous snake. Tonight, the cottonmouth hunts a swamp rat. The rat is

 A cottonmouth slithers through a Louisiana bayou in search of a meal.

65

[A Cycle of Life]

changes as small as 2° to 3° Fahrenheit (1° Celsius). NORTH AMERICA

The rat takes a drink at Louisiana Bayou Country

Atlantic Ocean

the water’s edge. The cottonmouth lunges forward. It

Gulf of Mexico

sinks its fangs into the rat’s 0 0

250 Miles 250 KM

body, and the fangs inject poison. Then the snake

 North America’s Louisiana bayou country

releases its prey. The swamp rat tries

warm-blooded, and the snake

to flee. It heads into thick

has no trouble locating the rat

grasses along the bayou’s

in the dark. It sens-

banks. It is too late. The

es the rat’s body

rat dies quickly from the

There are about 250 species

heat. Cottonmouths,

poison. The snake follows

of snakes in the United States.

also called water

its prey by scent. Coming

Of these, between 10 and

moccasins, have

upon the rat’s body, the

15 percent are poisonous.

built-in thermome-

cottonmouth touches the rat

These include cottonmouths

ters. Temperature

with its tongue. One touch

(water moccasins), rattle-

sensors lie in pits

assures the snake that its

snakes, copperheads, and

between their eyes.

prey is dead. Cottonmouths

coral snakes.

These snakes can

eat only dead prey, which

sense temperature

they swallow headfirst.

!

WOULD YOU BELIEVE?

66

 Snakes are cold-blooded. They enjoy sunning themselves on rocks on a hot afternoon.

Breeding Season

mouth. The pair will

 LOOK IT UP!

mate, but then will

Most people confuse the poi-

4 A female cottonmouth

probably never see

sonous cottonmouth with other

slithers through the reeds lin-

each other again.

harmless water snakes. Visit

ing the bayou. She is fully

The female car-

these Web sites and learn more

grown, measuring 2 feet (.6 m)

ries her young inside

about water snakes in North

long. Her back is dark olive,

her body for three

American wetlands: http://www.

and her belly is a paler yellow.

to four months.

uga.edu/srelherp/snakes/

It is spring, and the female is

She produces 10

novenom_2.htm and

ready to breed. Cottonmouths

live young. Nor-

http://www.southalley.com/

normally breed every two years.

mal cottonmouth

album_nerodia.html.

The female finds a male cotton-

females deliver 67

[A Cycle of Life]

!

WOULD YOU BELIEVE?

All snakes have teeth, but only

from one to

attracting small frogs or

twelve young.

fish. Their prey mistakes

At birth, the

poisonous snakes have fangs.

the shaking tails for worms

Fangs are hollow teeth that

young snakes are

or caterpillars. The young

deliver poison. They work like

about 9 inches (23

snakes are already able to

hypodermic needles at the doc-

cm) long. Their

inject prey with venom when

tor’s office. The fangs cut into

bodies are almost

they are born.

flesh. Poison from sacs in the

as wide as a nickel.

snake’s skull pours through the

Young cotton-

eye out for predators. While

fangs and into the snake’s victim.

mouths have

cottonmouths are small,

bright-colored,

owls, hawks, eagles, snapping

coppery bands

turtles, and alligators prey on

juvenile (JOO-vuh-nile)

on their backs.

them. Adult snakes, includ-

young, not yet having

Their tails can be

ing other cottonmouths, also

reached adulthood

yellow or yellow-

eat young water moccasins.

?

WORDS TO KNOW . . .

green. As the snakes grow, their body colors change from orange to dull olive or black.

68

Juveniles keep a wary

Cottonmouth Characteristics 4 Cottonmouths are the

From birth, juvenile

only venomous water snakes

cottonmouths hunt their own

in North America. The snake

food. They shake their pale

gets its nickname from the

yellow-green tails in the air,

snow white lining of its

[A Cycle of Life]

mouth. A cottonmouth will often coil its body into a spi-

Female Cottonmouths

ral. It leans its head back and

4 Female snakes

opens its mouth wide, display-

do not make good

Relatives of the cottonmouth

ing the white lining.

mothers. Once their

are found in Central America,

!

WOULD YOU BELIEVE?

Asia, and Europe.

 Juvenile cottonmouths have to be on their guard if they don’t want predators like this short-eared owl to swoop down and catch them.

69

 It is easy to see how this fierce cottonmouth got its name. Its mouth is lined in white.

children are born, they

70

The cottonmouth female

abandon them. The young

of the bayou has lost most of

must fend for themselves

her litter to predators. Only

against predators.

one snake survives to adult-

[A Cycle of Life]

hood. It feeds on fish,

sun for body heat. As night

frogs, lizards, birds, mice,

approaches, the female snake

rats, and other snakes.

slips from her warm perch

Cottonmouths eat their

into the water to hunt.

food whole. Their bodies

Our female escaped

easily digest fur, feathers,

eagles, king snakes, and

and bones.

largemouth bass

The surviving snake is

during her life. She

 DON’T DO IT!

a female. She grows quickly

slipped past great

Don’t risk a bite from a water

and soon stretches 4 feet

blue herons and

moccasin. If you see one, keep

(1.2 m) long. As she grows,

snapping turtles.

your distance. Do not try

she sheds her tight, too-small

Unfortunately, she

to catch it. Don’t throw rocks

skin. She slithers around a

could not escape

at it or poke it with a stick.

tree branch or over a rough

disease. Her body

These snakes may attack. If

rock to remove the old skin.

carries parasites.

you are bitten, go to a hospi-

In the past year, she has

They have infected

tal immediately.

shed her skin four times.

her lungs. She has

During the day, cotton-

also developed

?

WORDS TO KNOW . . .

mouths sun themselves on

ulcers, or open

parasites (PA-ruh-sites)

warm rocks or tree branches.

sores, in her

animals that live on or in

Snakes are cold-blooded.

stomach and

another animal in order to

They cannot keep themselves

intestines. The

feed off of it

warm and must rely on the

parasites and 71

[A Cycle of Life]

 When a cottonmouth dies, it becomes food for fly maggots and other insect larvae.

ulcers bring the cottonmouth

tender scraps to their young.

to an early death.

Nutrients from the rotting

She dies at the water’s

72

flesh sink into the ground.

edge. Her body is now food

They feed the plants that hid

for carrion feeders. Insects

the cottonmouth while she

lay eggs on her flesh. Birds

lived. This is the wetland cycle

peck at the meat, carrying

of life.

8

[Chapter Eight]

The Land of Trembling Earth

The Land of Trembling Earth

4 A mother black bear and her cubs step carefully on a hammock in the depths of the swamp. She knows by instinct that this “land” within the swamp will shake beneath her weight. Though this island supports the growth of black

 Step into the land of the trembling earth—the Okefenokee Swamp.

73

[ T h e L a n d o f Tr e m b l i n g E a r t h ]

gum trees and loblolly bays, it

496,000 acres (200,700

is not true land. It is a massive

hectares). Roughly 70 islands

peat island, floating in the

emerge above the dark water.

deep brown waters. It is called

Within the swamp, a variety

the Okefenokee, named by the

of habitats exist. Among these

Creek, an American Indian

ecosystems are pond cypress

tribe, and it means “the land

forests, evergreen forests,

of trembling earth.”

black gum forests, wet prairies,

High above, ?

WORDS TO KNOW . . .

long-legged wood

shrub wetlands, and floating peat islands.

watershed (WAW-tur-shed)

storks squawk and

Most water in the

the region or land area that

flutter as they build

Okefenokee Swamp comes

drains into a river or lake

their nests. Wood

from rain and runoff. The

storks are not terri-

watershed that feeds the

torial. They happily live within a few feet of other nesting pairs. This black gum has more than a dozen wood stork

NORTH AMERICA

nests, stacked one above anoth-

Atlantic Ocean

Okefenokee Swamp

er like apartments. Georgia’s Okefenokee Swamp is North America’s

Gulf of Mexico 0 0

250 Miles 250 KM

largest swamp. It covers about  North America’s Okefenokee Swamp

74

 Okefenokee water is pure and drinkable—even if it is the color of strong tea.

swamp covers more than 1,400 square miles (3,626 sq km).

poisonous water moccasins. Okefenokee’s peat is the

Precipitation in the region usu-

result of thousands of years

ally adds up to 50 inches (127

of dead water lilies and pieces

cm) a year, and most is from

of cypress trees. The peat is

rainfall. In many places, people

thick, solid, and floating.

could easily wade through the

It dyes the water a deep

water, because it is rarely more

brown, just like dark tea.

than 2 feet (.6 m) deep. Of

The water is exceptionally

course, waders would be shar-

pure because the peat “brew”

ing space with alligators and

makes it acidic. Mold, mildew, 75

[ T h e L a n d o f Tr e m b l i n g E a r t h ]

and spores cannot grow in or pollute the water. Only acid-

Living in the Swamp

loving plants can survive in

4 Okefenokee supports more

this water.

than 600 species of plants and 425 species of animals. The dominant plant is the cypress tree. Pond cypress and bald cypress rise above the swamp, shading the land and water below. Their knobby trunks may represent nearly 500 years of growth. Cypress trees are related to conifers (conebearing trees), but unlike conifers, they shed their needles each year. In other regions of the swamp, loblolly bay grows beside spiky, dark green holly. Slash pines drop their needles, creating a rust brown carpet on the earth below. Climbing heath and  Wax myrtle and cypress loom above the hammocks of the swamp.

[ T h e L a n d o f Tr e m b l i n g E a r t h ]

greenbriar snake their way up tree trunks. In the wet prairies, water lilies pave a white-and-yellow road amid tea brown water. Golden club and yellow-fringed orchids add a touch of sun to the swamp’s gloom. Pickerelweed emerges from the water. On clumps of damp earth, swamp iris open their delicate petals of blue and yellow. Not all Okefenokee plants are lovely or safe. There is poison ivy nestled next to deep

 Pitcher plants do not actually eat their prey; they digest the nutrients from the prey’s body.

purple violets. Feathery poison  LOOK IT UP!

sumac waves in the gentle

Pitcher plants

Georgia breezes.

attract insects into

Learn more about the

their cup-shaped

Okefenokee Swamp. Access this

The Okefenokee supports four

flowers. Once

Web site: http://www.

types of carnivorous plants:

inside, there is no

sherpaguides.com/georgia/

pitcher plants, sundews, butter-

exit. Insects are

okefenokee_swamp/index.html.

worts, and bladderworts.

digested by plant

Insects should be wary.

77

Okefenokee Animal Life 4 Birds make up the majority of the animals in the swamp. About 235 species live full- or part-time in the Okefenokee. The largest bird there is the sandhill crane. With their 7foot (2.1-m) wingspans, sandhills make a dramatic picture in flight. Sandhills stand 4 feet (1.2 m) tall. Their height allows them to see approaching danger. These cranes trumpet an  The sundew’s glue-covered hairs hold fast to insects they catch.

juices. Sundews and butterworts use a gluey substance

78

alarm that has earned them the nickname “watchmen of the swamp.” Wading birds spend their

to hold on to their prey. Blad-

swamp days bobbing their

derworts live and feed beneath

heads up and down in the

the water. They have small

shallow water. They peck in

openings into their bladders

the muck for crustaceans,

that act like trapdoors.

frogs, toads, snakes, and

Great egrets nearly became extinct when the birds were killed so that their  feathers could be collected for ladies’ hats.

[ T h e L a n d o f Tr e m b l i n g E a r t h ]

insects. Two common species

These noble white birds

among swamp wading birds are

once suffered greatly from

the white ibis and the great

human activities. Their beauti-

egret. White ibises are noted

ful feathers were used as deco-

for their sharp curved bills and

rations for women’s hats.

long orange-pink legs. White

Unfortunately, the feather col-

ibises feed on insects and cray-

lectors usually killed the feath-

fish. The great egret hunts

er producers, which seriously

fish, frogs, and snakes.

reduced the egret population.

PROFILE: CROAK, OINK, BELLOW

Protective laws and fashion

Each night, the Okefenokee chorus

changes have given the egret

gathers to present a concert. The pig

population an opportunity to

frog opens the night’s entertainment

grow.

with a few piglike grunts. The river

Osprey, owls, and vul-

frog snores. The bullfrog croaks. Male

tures hunt their food in

leopard frogs sound much like the

Okefenokee. Osprey feed on

squeak of hands squeezing the open

fish, which they find easily

end of a balloon. The green tree frog

enough in swamp waters.

joins in with its honk, while the bark-

About 36 types of fish swim

ing tree frog yelps like a dog pack.

in Okefenokee’s waters. Owls

Add to that the banjolike notes of the

prefer hunting at night. The

bronze frog and the charming tones of

barred owl ruffles its feathers,

the southern toad. High notes and

then swoops down to catch

low, loud notes and soft, the frog and

rats, mice, or ground birds.

toad choruses sing the music of the

Vultures perform a needed

swamp—and the concert is free for

service. They eat dead flesh.

any who choose to listen.

In this way, they clean dead animal bodies from the land. Migratory ducks and geese arrive in Okefenokee in time to spend a mild winter there. When spring

80

 There is a risk that Okefenokee’s white-tailed deer population may grow too large for the swamp to support it.

comes, they fly north to nest

pounds (136 kg). White-

and breed.

tailed deer also thrive in

About 50 types of mam-

the Okefenokee, as there

mals inhabit the swamp. The

are no major predators to

largest is the Florida black

slow their numbers.

bear. This small cousin to the grizzly grows to about 300

Otters and raccoons provide a bit of humor for 81

can open any cooler with ease and will take anything from peanut butter to ham sandwiches. No swamp would be complete without an array of reptiles. The Okefenokee reptile population is led by about 10,000 alligators. Once hunted for their skins, these  A river otter takes time from his play to enjoy a sip of water.

protected by law for many

swamp tourists. Finding an

years. Alligators are basically

otter is easy—just look for

shy and have no interest in

a mudslide into the water.

humans—with one exception.

Otters are fun and frisky.

A mother alligator protects

They love playing in the

her eggs from all creatures,

water and can swim quite

regardless of size. Females

fast. Raccoons, like bears,

will attack humans, bears,

eat anything. This includes

raccoons, or sandhill cranes

campers’ food supplies.

in defense of their young.

Raccoons have agile hands and clever minds. They 82

fierce predators have been

The swamp supports more than two dozen species of

[ T h e L a n d o f Tr e m b l i n g E a r t h ]

snakes. Most are harmless, but

build the Suwannee River Sill,

not all. The largest and most

an earthen dam that holds

deadly is the water moccasin,

water in the swamp. It raises

or cottonmouth. Coral snakes

the swamp’s water level and

and eastern diamondback

supposedly prevents fires

rattlesnakes are the other poi-

because the fires cannot jump

sonous members of the

from place to place. Surprising-

swamp. One of the most stun-

ly, swamps are a mix of wet

ning swamp snakes is the rain-

ground, underwater ground,

bow snake. Its black body gleams in the sun, along with brilliant red stripes and a yellow underbelly.

Threats to the Okefenokee Swamp 4 Many years ago, natural fires that were started by lightning strikes plagued the swamp. People living near the swamp feared the loss of their homes and farm crops. The answer to their problem was to This rainbow snake is not poisonous, but many other local snakes carry a venom-packed bite.

[ T h e L a n d o f Tr e m b l i n g E a r t h ]

and dry hammocks. The more

Du Pont Corporation holds

dry stuff, the easier it is to

the rights to mine land rich

spread fires. The sill seemed

in titanium. Titanium is used

like a good idea.

to make titanium oxide. This

Over the years, the earthen dam was expanded and

(and your teeth). It is also

strengthened with concrete.

used to produce plastic prod-

The swamp’s water has natural-

ucts and print the letters on

ly high levels of acid. That acid

M&M candies.

has eaten away at the sill’s con-

Du Pont wants to mine

crete and steel water controls.

the land for this valuable min-

Today, the sill has acid-burned

eral over a 50-year period. Over

holes the size of dinner plates.

time, the company would

Water leaks through the holes

develop new pine-and-grass

and creates strong currents.

wetlands on the used land.

Experts disagree on whether

Ecologists feel that mining of

to repair or remove the sill.

any kind will result in perma-

However, both sides agree

nent damage to the swamp.

that human interference will

Two rare or endangered

change the nature of this

species that live in the swamp—

valued wetland environment.

the indigo snake and the

On one side of the swamp known as Trail Ridge, the 84

compound whitens toothpaste

gopher tortoise—may be hurt by the mining. The gopher

[ T h e L a n d o f Tr e m b l i n g E a r t h ]

 The gopher tortoise digs burrows that burrowing owls, foxes, opossums, raccoons, skinks, and snakes will later live in.

tortoise digs its burrows along

gopher frogs, red-tailed skinks,

Trail Ridge. The gopher tor-

diamondback rattlers, and east-

toise is Georgia’s state reptile.

ern indigo snakes. Ecologists

It is also a keystone species of

hope that the survival of these

the region. Its burrows are

creatures will be considered

homes for burrowing owls,

before actions damage the

foxes, opossums, raccoons,

delicate swamp ecosystem. 85

9

[Chapter Nine]

The Human Touch

The Human Touch

86

Salt water washed in and out. Fish spawned and produced young. In the 1960s and 1970s, war raged between North Vietnam and South Vietnam. A chemical was used to kill

4 The mangrove and swamp

plant life throughout the area.

forests of Vietnam stood for

That chemical, Agent Orange,

thousands of years in Asia.

was highly effective. The war

[ T h e H u m a n To u c h ]

destroyed nearly half of the mangrove swamps in the Mekong Delta. A

The chemical did not go

S

I

A

away. Monsoons came, and Mekong Delta

rain poured through the jungles. Runoff and groundwater

0 0

1000 Miles 1000 KM

carried Agent Orange into the mangrove swamps. The

 Asia’s Mekong Delta

chemical did its job, and the

continue to cut trees

mangrove died. Today, more

for timber, erosion

than 30 years later, attempts

has also become a

monsoons (mon-SOONZ)

to replant the swamps still

serious threat.

winds that reverse direction

fail. The success of Agent

Fertilizers,

Orange continues long after

plant killers, and

the war ended.

pest killers can

?

WORDS TO KNOW . . .

with the seasons

 READ IT!

be used hundreds

Wetlands are disappearing.

of miles away and

Learn about how these vital

4 Major threats to wetlands

still affect an

ecosystems can be saved in

come from chemical pollution,

ecosystem. Chem-

Anita Louise McCormick’s

sewage, industrial pollution,

icals enter wetlands

Vanishing Wetlands (Lucent

human activity, and alien

through runoff

Books, 1995).

species. In areas where humans

or groundwater.

Threats to Wetlands

 U.S. Air Force planes spray Agent Orange on wetlands along the Mekong River.

87

[ T h e H u m a n To u c h ]

 DO IT!

Although wetland

can eventually affect birds

Reduce chemical runoff from

plants and soil can

of prey, large fish, mammals,

your home. Use biodegradable

filter out some of

and even humans.

cleaners and detergents because

the pollution,

they can be broken down

humans produce

naturally and are less harmful

far more pollution

4 Every swamp, bog, and fen

to the environment than non-

than can be cleaned.

serves a purpose. Each one

People Problems

Plant and pest

helps clean our environment.

raked leaves and grass clippings

killers remain poi-

Unfortunately, many wetlands

out of storm drains.

sonous long after

lie on land humans want.

biodegradable cleaners. Keep

their original use. These chemicals travel through

years ago that they could fill in

the water cycle. Plant killer

wetlands with dirt and use the

used in Orlando, Florida, can

land. Some wetlands have been

kill sawgrass in the Everglades,

turned into farms or cattle

which is several hundred miles

ranches. Others are now hous-

to the south. Pest killers

ing developments, golf courses,

destroy harmful weevils and

and vacation resorts.

locusts but also kill butterflies,

88

People discovered many

In the 1600s, the land cov-

dragonflies, and praying man-

ered by the lower 48 states

tises. The poison that kills

held 220 million acres (89

insects gets into the bodies of

million hectares) of wetlands.

insect eaters. Collected poisons

These ranged from massive

 A bulldozer fills a wetland with topsoil. In a few months, this swamp will be a housing development.

swamps to temporary potholes

dredged, tilled, mined, grazed,

and playas, which are dry

and polluted each year. Pro-

riverbeds of ponds that hold

grams to rebuild wetlands

water only part of the year.

cannot keep up with projects

Today, wetlands in the conti-

that destroy them.

nental United States span

The loss of wetlands to

about 105 million acres (42

farms, housing, and recreation

million hectares). Of those,

is a worldwide problem. Many

about 58,000 acres (23,000

people want a beachside home,

hectares) are filled, drained,

but few realize the heavy toll 89

[ T h e H u m a n To u c h ]

that results. Animals and

life. Similar situations exist

plants lose their habitats. The

everywhere people live.

land can no longer clean itself,

People need to stop de-

so pollution increases. About

stroying wetlands and begin

40 percent of freshwater in the

rebuilding them. Wetlands

United States is too polluted to

have been set aside as nature

drink. Many wetlands no

preserves, national parks, and

longer support fish or plant

protected habitats. Wetlands also can be used to clean water naturally, cheaply, and effectively. Some countries have found it cheaper to rebuild a wetland than to build a new sewage treatment plant. Australia manages more than a dozen wetland water treatment centers.

Strangers 4 Alien species have become a worldwide problem. Nonnative species arrive from other places and take over  A biologist examines a Louisiana swamp for industrial pollution.

[ T h e H u m a n To u c h ]

their new homes. Worldwide travel, shipping, and business have expanded alien species problems. Some alien water plants have entered wetlands through sewer systems. Aquarium plants flushed down the toilet can seriously damage wetlands. Once an alien species settles in, it is hard to contain. Bringing in predators to attack the invaders just creates new problems. An endless cycle of introducing more predators takes hold. Alien species with no nat-

 Nutria may be alien species, but they do not harm their bayou environment.

beaver’s natural predators. Milfoil creates serious prob-

ural enemies throw off nature’s

lems because it has no natural

balance. Consider the situation

enemies. The best answer is to

of two species alien to North

reduce the occurrence of alien

American wetlands: nutria and

species in wetlands. If not,

milfoil. Nutria are enough like

already endangered wetlands

beavers to be eaten by the

will die. 91

Chart of Species

[Wetlands]

KEYSTONE SPECIES

FLAGSHIP SPECIES

UMBRELLA SPECIES

INDICATOR SPECIES

AFRICA

Nile crocodiles, hippopotamuses, papyrus, marsh grasses

purple herons, glossy ibises, shoebill storks

Nile crocodiles, hippopotamuses, various wetland raptors

mussels, snails, clams, dragonflies, caddis flies

ASIA

marsh grasses, ducks, geese

pitcher plants, glossy ibises, Eurasian spoonbills, purple herons, Eurasian golden plovers

Eurasian spoonbills, glossy ibises, various wetland raptors, Eurasian golden plovers

mussels, snails dragonflies, damselflies, caddis flies

AUSTRALIA

peat moss, mangroves, red crabs

pitcher plants, black swans, glossy ibises

black swans, glossy ibises, various wetland raptors

mussels, snails, dragonflies, caddis flies

EUROPE

peat moss, marsh grasses, ducks, geese, beavers

beavers, Eurasian spoonbills, purple herons, old world pelicans, Eurasian golden plovers

beavers, Eurasian spoonbills, Eurasian golden plovers, various wetlands raptors

mussels, snails, dragonflies, damselflies, caddis flies

NORTH AMERICA

mangroves, alligators, marsh grasses, beavers, lesser snow geese, American crocodiles

pitcher plants, Venus flytraps, whooping cranes, trumpeter swans, American crocodiles

alligators, Florida panthers, whooping cranes, various wetland raptors

mussels, snails, clams, dragonflies, damselflies, caddis flies

SOUTH AMERICA

mangroves, water lilies, hoatzins, greater flamingos

hoatzins, greater flamingos, giant river otters

giant river otters, macaws, anacondas

mussels, snails, dragonflies, caddis flies

CONTINENT

 The above chart gives a starting point for identifying key species. Each wetland environment has its own key species. The above chart lists some of those species.

92

[Bold-faced entries are the ones discussed in the text.]