World of animals 3 sea mammals by Angel C

Seals,

Sea Lions, Whales, Dolphins, Manatees

Digitized by the Internet Archive in

2015

https://archive.org/details/mammalsworldofan03patm

WORLD

Seals,

ANIMALS

Sea Lions, Whales, Dolphins, Manatees

PAT MORRIS, AMY-JANE BEER

GROLIER

...

Published 2003 by Grolier,

Danbury, CT 06816

division of Scholastic Library Publishing

This edition published exclusively for the school

and

market

library

Planned and produced by

Andromeda Oxford Various species of sea

mammals: the harbor seal—a

Limited

11-13 The Vineyard, Abingdon, Oxon 0X14 3PX

typical true seal (1);

the walrus

Cape fur

(2):

vwvw.andromeda.co.uk

and the

seal, a species

eared seal

Andromeda Oxford

2003

Limited

(3).

reserved. No part may be reproduced, stored

All rights

or transmitted

of this publication in

a retrieval system,

any form or by any means

electronic, mechanical, photocopying, recording,

or otherwise, without the permission of the

Congress Cataloging-in-Publication Data

Library of

Morris, Pat. / (Pat Morris,

cm.

Contents:

Amy-Jane

Beer, Erica Bower],

(World of animals) 1.

Small carnivores

-- V.

Large herbivores

Angela Davies, Penny Mathias

Editors:

Art Editor and Designer: -- v. 2.

Large carnivores

Sea

mammals -

Rodents 2 and lagomorphs

Steve

Marian

Editorial Assistants:

Dreier, Rita

Demetriou

McCurdy

Tim Williams

Cartographic Editor:

Ruminant (horned) herbivores -- v. 7. Rodents 9. Insectivores and bats - v. 10. Marsupials. ISBN 0-7172-5742-8 (set alk. paper) - ISBN 0-7172-5743-6 (v,1 alk. paper) - ISBN 0-7172-5744-4 (v.2 alk. paper) - ISBN 0-7172-5745-2 (v.3 alk. paper) - ISBN 0-7172-5746-0 (v.4 alk. paper) - ISBN 0-7172-5747-9 (v.5 alk. paper) - ISBN 0-7172-5748-7 (v.6 alk. paper) - ISBN 0-7172-5749-5 (v.7 alk. paper) - ISBN 0-7172-5750-9 (v.8 alk. paper) - ISBN 0-7172-5751-7 (v.9 alk. paper) - ISBN Primates

Graham Bateman

Project Director:

Mammals

Picture

Manager:

Claire Turner

Picture Researcher:

Vickie Walters

Production:

Clive Sparling

•

0-7172-5752-5 1

III.

(v.10

Researchers:

Dr. Erica

Bower, Rachael Brooks,

alk.

Rachael Murton, Eleanor

paper)

Mammals-Juvenile literature. [1. Mammals.] Title. IV. World of animals (Danbury, Conn.)

Beer,

Amy-Jane,

II.

Bower,

Thomas

Erica.

Origination: Unifoto International, South Africa

QL706.2 .M675 2003

China

Printed

Set ISBN

0-7172-5742-8

599-dc21

2002073860

About This Volume

mammals form

three orders of

at sea.

The

seals

and sea

lions (Pinnipedia)

do come onto

life in

the

the water, including

spend most of

land, but nevertheless

their time

Marine mammals are streamlined to make swimming as easy as possible, and several species undertake longer

migrations than any land precious body

warmth

and are insulated by

many have complex

mammals. Sea mammals tend

to be large, since a larger

body

the cold water. Seals and sea lions have dense fur to keep a thick layer of fat (called blubber) underneath.

social behavior.

Some

efficient at retaining

them warm, but whales have

Cetaceans are highly

intelligent animals,

a bare

and

seals are sociable, but others live their lives alone. All sea

mammals have

Many

populations are

suffered badly from overhunting for their meat, furs ic

of which (Cetacea and Sirenia) are so fully adapted to

water that they never come on land. They have no hind limbs and must do everything

suckling their young.

skin

mammals, two

(in

seals

and sea

lions),

and

fat (whales).

now

danger of extinction and are protected by international agreements. Reduced populations are a particular problem

because

all

sea

mammals

take

often do not breed every year.

many If

too

years to reach breeding age and only produce

many

are killed,

one young

at a time. Also, they

takes decades to restore populations to their former numbers.

Contents

How to Use This Set

Spinner Dolphin

Find the Animal

Harbor Porpoise

SEALS AND SEA LIONS

Beluga

Northern Fur Seal

Narwhal

Cape Fur Seal

Sperm Whale The beluga can make

Steller's

Northern Bottlenose Whale

Sea Lion

California

Sea Lion

Walrus

Gray Whale

Blue Whale

102

Minke Whale

106

Crabeater Seal

Southern Right Whale

108

Leopard Seal

Bowhead Whale

110

Harbor Seal

List

of Species

112

Gray Seal

Glossary

Monk Seal

Northern Elephant Seal

114

SEE ALSO

Seal,

Cape

Fur 3:16; Seal, Harp 3:44

five years old

they stand

little

SEALS AND SEA LIONS NORTHERN FUR SEAL

were highly

harvesting for their skins. Pelts

warmth and

prized for their

making

also for

fashionable fur coats. However, since the fur seal rarely

to breed, large

comes ashore except

numbers were shot

The method was

at sea.

cruel and wasteful because

many

bodies were

never recovered. Once the breeding beaches

had been discovered by Russian hunters, the took place there.

killing

was an

easier

operation and more efficient.

Attempts to control exploitation of the seals failed, since

difficult to

protect wildlife

international waters. The population

living in

dwindled to

less

than 10 percent of the original

number, and some colonies died out altogether. But

1911 the various countries involved

agreed to make

killing

the seals

everywhere except on the

years after 191

some

For

illegal

Pribilof colonies.

young,

nonbreeding males were targeted Large numbers could be

culls.

effect

on the

killed

managed with no

overall breeding population

because many would never have bred anyway. That was

how

managed

until

the fur seal harvest

1984

was

been no

(there has

commercial harvesting since that time).

worked

ÂŠ

Females, pups, and

juveniles of the Pribilof Island

stock leave the breeding islands

late

November and migrate

as far south

as southern California

chance of securing breeding beaches

massive beachmaster gather nearby

and Japan.

the face of the

all-male groups.

they

worn

out.

Many

die before

they are more than about 12 years old and are replaced by a

few

At one time there were about 4 million fur

numbers were

steadily rising to

classic

example of successful conservation

management

involving sustainable harvesting

from a wild population.

Although the

seals are

numbers are

declining.

now

protected, their

The main breeding in

About 50,000 northern

fewer than 50 years.

fur seals

the

severely reduced by uncontrolled

drown

fishermen's nets each year. Another serious

problem

that fishermen have taken too

from the North

Pacific, leaving

reduced to a

level that

the previous numbers

many

diminished

resources for the fish-eating species. possible that the food supply

between

Kamchatka and Alaska. But before 191

was

than 2 million. The northern fur seal became a

fish

of the youngsters.

seals living in the North Pacific

time, the population

be taken. At the same

population has halved

The

beachmasters may be successful for a few years, but then get

seals to

Mysterious Decline

spot on the

bulls. Instead,

an annual harvest of

well, enabling

about 40,000

may have been

can no longer support of seals.

MAMMALS

SEA

'Vw''

Cape Fur

Seal

Arctocephalus pusUIus

The Cape fur seal

a typical fur seal

were exploited for

many years.

whose colonies

However, populations

remain large despite the heavy harvesting of pups. Common name Scientific

name

Cape

fur seal (southern fur seal)

Arctocephalus pusillus

The Family

FIRST

RECORDED CONTACT with the

Cape

fur seal

Otariidae

by a European was

Order

Pinnipedia

Size

Length: male 6-8

4-5,2

ft (1

(1,8-2 m); female

,2-1 .7 m);

tail

rounding the Cape of

Good Hope

the animals (together with penguins

ÂŠ A Cape

fur seal

baskirtg or) a rock

their eggs) for

food or

skins. Like

other fur

Skeleton Coast, Namibia.

seals,

the Cape has dense fur to keep

insulated

the cool seas.

The seals were

well

has attracted the

hunted

attention of commercial hunters since the early

neck and hind

colonization of South Africa

can be turned forward under

dark-blackish gray, female lighter

were

furs

valuable,

and

was

the 1650s.- The

extract useful

Spends most time

out on rocky

at sea; hauls

century by European sailors.

They have since

been harvested for

also possible to

oil

from the

seals. Indiscriminate

and unregulated hunting continued as

luxurious

late as

beaches of offshore islands

the 19th century, and the fur seal population

Breeding

Single

pup born October-November

gestation period of about

months delayed 1

year (including 4

implantation).

Weaned

1-24 months; sexually mature

May

live

after

was

up to about 18-20

4-5

severely reduced

in size.

years.

Controlled Harvesting

years; males

Fortunately, legal protection shorter-lived than females

numbers Voice

Bleating

and bellowing; breeding

to increase.

Mainly small

Diet

fish,

but sometimes octopus and

squid; occasionally lobsters

from 1893 allowed

was combined with

bulls roar

carefully organized culls

based on detailed

population studies, which allowed an annual

and crustaceans harvest of skins and stabilization of seal

Habitat

Islets

and rocky beaches with sandy bays

numbers. Most colonies are Distribution Cape subspecies

{A. p. pusillus)

breeds

hunting

fully

protected, and

confined to only a few. Quotas are

along coasts of South Africa and Namibia; Australian fur seal (A. p. doriferus)

found

set

Australian waters around Tasmania

Status

Population: about

million

African coasts, with 25,000

Tasmania; CITES

and enforced to prevent too many

from being taken. Even

around southern

still

more around

so,

seals

the annual harvest

sometimes exceeds 30,000 animals. The

Australian

Cape

fur seal population, like that

African waters, k 5:

has been

up to about 25,000 today.

Cape i.

also severely reduced

protected since 1891, and numbers have slowly built

was

numbers by uncontrolled hunting.

beaches

fur seals return'to their breeding

the spring, with the old bulls hauling

themselves ashore about October. Those that arrive first find

empty beaches and can

territory fairly easily, in

SEE ALSO

.'.ihprn

-<!(

3:14, Seal, Harp 3:44

set

but they have to be very fat

order to survive the long weeks without

first

the 15th

and browner; narrow, pointed ears Habits

on the

Typical fur seal with long

belly: bull

often

and

cm)

flippers that

sailors killed

1483. Subsequently,

about

length:

Weight Male 440-770 lb (200-350 kg); female 79-270 lb (36-122 kg) Key features

many

fur.

their

SEALS AND SEA LIONS CAPE FUR SEAL

feeding.

they leave their beach, they

their territory to others. Later arrivals

fewer

fat reserves,

to fight their bulls.

all

and

a bigger struggle

among

Younger males stand

landing at well

way

but find

ashore

little

the established

chance of

gather

will usually

away from the main breeding

adult bulls hold

beach

will lose

need

territories,

posturing

the pregnant females arrive a

two

later.

The females

territories of

settle

often squabbling viciously

rivals

week

down

the beachmaster

The

bulls,

the

themselves over space. Groups of up to

50 or more females gather around each territorial bull, usually in

an area of

square yards (58

sq. m).

less

than 70

here that they give

birth to their pups.

groups

areas.

aggressively, bellowing, and fighting off until

among

There

a strong

bond between

female

and her pup. She recognizes her own offspring by

its call

others

all

and scent despite the hundreds of around. After suckling her pup, she

goes to sea again to feed, leaving the pup

alone for several days.

returning from

the sea, the females are ready to mate.

While

mothers are away, the

their

pups often gather

small

"playground areas," splashing

around

shallow pools,

learning to swim. By mid-

December the females begin ,

and the pups are

to disperse,

enough

large

to follow them.

However, the animals do not go far

and stay near the breeding

beaches

all

year round.

seals generally

to sea

â&#x20AC;&#x201D;those

Cape

do not range

fur

far

out

African waters stay

within about 100 miles (160 km) of

the coast.

At about four months the pups feed increasingly on

fish,

but

may

still

take milk from their mother at nearly

one year

old.

Males do not breed

until

they are strong enough to win a territory, 1

which can often take up to

years.

bull usually

holds a

breeding territory for three years, after

which he

weak

probably too

to continue dominating

the territory and

its

females.

MAMMALS

SEA

Sea

Steller 's

Lion The huge

Steller's

cause

iikeiy

Eumetopias jubatus

sea lion

now in

deciine.

The most

overfishing in the North Pacific, but

other factors, inciuding poiiution and changes in sea Order Size

Length: male 9-10.5

female

may

currents,

Pinnipedia

5-9, 5

ft (2.

be contributing

to its

7-3, 2 m);

3-2. 8 m) Steller's sea lions are large, noisy beasts

Weight Male 1,980-3,970 lb (9001,800 kg); female 580-770 lb

(263-350 kg)

Key features

Largest species of sea

golden yellowish-brown

lion; fur

when

appears dark-

dry,

brown when wet Habits

Spends most of in

Breeding

Single

rest

time swimming and diving

comes ashore

to breed

pup born May-July

delayed implantation).

after gestation

Weaned

months; sexually mature live

They

and to

shelter

12-24

years.

Females

over 30 years, males rarely more

Loud barking and bellowing,

especially

the cool

warm,

air.

breeding grounds from April onward, returning

from

far

fish, particularly pollock,

Often a

bull will

islands; sea caves

Distribution North Pacific coasts from California to Japan

being ousted by a younger is

same

be large enough or

unlikely to

years old. decline

rival.

demanding

The struggle

that bulls are sufficiently

strong to succeed until they are at least nine

Once on

Population: probably fewer than 89,000; in

to the

section of beach for several years before

for a territory

lUCN Endangered. A species

come back

but also

squid and octopus

Rocky coasts and offshore

out at sea to the same place year after

where he was born and then defend the

area

salmon, herring, mackerel, and sometimes

Status

begin to assemble at the

Territorial bulls

same

Habitat

sea caves, where their

Islets

breeding grounds

Mostly

small

Beach Defense

year.

Diet

come ashore on

wet bodies steam gently

than 15

Voice

inquisitive, Steller's

away from people and

sea lions tend to keep

and bask

period of 11.5 months (including 3-4 months

may

which are bolder and more

boats.

its

coastal waters, but

and to

associated with the cool seas and rocky shores of the North Pacific. Unlike California sea lions,

their territory, they stay

onshore without feeding for the whole of the breeding period. Lack of food and the stress of

defending their section of beach take toll

on the adult

bulls.

to keep their patch for

seasons. years,

Most

will

Few

heavy

manage

not survive beyond about 15

come ashore

live

twice as long.

to give birth from

May onward. The crowded

early

will

more than three

although females may

Females

them

breeding

rookeries provide a deafening spectacle from

May

to late

July,

with bleating pups and

bellowing from the adults

all

day and night.

During the breeding season the females rarely

swim more than 18

miles (30

km) from

the colony to feed, making shallow dives of

SEE ALSO

Seal,

Cape

in fights.

enormously thickened, especially

around the neck, where

superiority, but

use them

can be over 2 inches

Fur 3:16; Sea Lion, Steller's 3:18; Sea Lion, California 3:20

SEALS AND SEA LIONS WALRUS

cm)

thick,

with an underlying layer of

4 inches (10 cm) of

The

fat.

fat effectively

protects the animals from causing each other

damage with

serious

wounds around

massive

caused during

although

their tusks,

may be

the shoulders

territorial fights.

Feeling for Food The walrus feeds by diving water, rarely

deep.

more than 100

down

can stay

shallow feet (30

for 10 minutes,

but most dives are shorter than that.

The tusks appear not to be used during

feeding and would probably signs of

wear

they were. Walruses

feed on a variety of mollusks that they obtain from the seabed. They have

about 450

stiff bristles

around

their

mouths, a shorter and more numerous

bunch of whiskers than seal.

They are embedded

any other type of

sensitive skin, so

that the walrus can gently brush

Its

bristles

along the seabed, feeling for solid objects, such

Much

as clams.

feeding has to be guided by

touch, especially

when uses

its

murky waters and

dark most of the time.

massive, fleshy

water into the sand

lips

winter,

walrus then

to squirt jets of

at the seabed, thereby

exposing the buried clams and other mollusks

hidden there. They are then scooped up and

may be crushed by

the large, flat-topped molar

teeth before being swallowed. Usually, the

animal eats large clams or seasnails by holding the shells

In its lips

and sucking out the

then drops the empty

shell

and

flesh.

starts to eat

another. Doing so saves swallowing lots of shell

fragments. Several thousand mollusks

eaten

a single feeding session.

invertebrates are found

cucumbers, and crabs

worms, sea

â&#x20AC;&#x201D;some of which may be

very large, weighing 2

ÂŠ

Other seabed

and consumed

similar way. Prey includes

may be

pounds

(0.9 kg) or more.

The enormous tusks of the walrus are a source of

ivory both harder

and denser than

a result, the animals

that of elephants.

have been ruthlessly exploited.

SEA

MAMMALS

Over 60 different types of prey have been

large floating islands of ice

recorded. Occasionaiiy, fish are eaten, especially

them

flounders and others

living

on the seabed,

younger animals

walrus can consume about 100 pounds

v45 kg) of food every day,

about 6 percent of

may

they

Homes

The walrus

continental shelf.

pack

ice,

winter.

migrating south as the ice extends

As the

ice

but white

melts

skin

when warm

when

they are swimming

brown

color

all

the spring, the

several

the edges of the permanent

The annual traveling

summer

and tend to

bully

wairus societyâ&#x20AC;&#x201D; the

wairus with the iargest tusks

generaiiy the

dominant animai.

This

can iead to stabbing

animais with simiiarsized tusks in

may be lying

each other to

(1),

untii

away

(2).

They

occasionaiiy use their tusks to heave

themseives out of the sea onto the ice as head-rests

(3)

and

(4).

involve

miles

;3,000 km) each year. The animals prefer to use ice rather than land

on beaches.

where the

winter they stay

ice

but

relatively thin,

are capable of using their heavy

heads to break open

ice

up to 9

inches (23 cm) thick. The ice holes

allow

them

summer

surface. In the

Walrus

and to swim

to breathe

they

live

at the

among

Ivory

usks are present

both sexes of walrus, and very

occasionally an animal

may have

three of

instead of the usual two. Tusks are larger

grow

the males, and can long.

native people

straighter

more than 30 inches (76 cm)

The longest tusk on record weighed nearly 12

pounds

(5.4 kg).

The tusks are oval

have grooves along

their length.

cross section

entirely

composed

bulk of our

own

Walrus tusk ivory

SEE ALSO

and

being almost

of dentine, the material that forms the

teeth, with is

little

or no

highly prized, since

Elephant, African 5:16

enamel covering. it

many ivory

The tusks have been used by

ivory.

the Arctic for generations, carved into

types of ornaments, toys, and useful tools. Walrus

was

a valuable souvenir of Arctic voyages,

and

extensive hunting of walruses for their ivory led to major

They are massively

extended canine teeth and are unusual

and

denser than elephant

them

harder and

populations. The 1989 ban on international

declines

trade

African elephant ivory put further pressure on

stocks of walruses as a source of substitute

more than 12,000

Some

are killed every year

scientists believe that

animals has been taken

one

concedes defeat by turning

During January and February females and

may

Tusks signify status

dueis between dominant

establish occupation of the best sites.

ice cap.

cycle of migration

more than 1,800

cold

thousand strong, with the animals

sociable

the Chukchi Sea along

the sun,

packed close together. Yet they are not very

the Bering Sea, then moves northward around

duly to September)

over. Outside the breeding

main American population spends the winter

of Alaska to spend the

season males and females tend to associate separate groups. Often the groups

tip

month

that time

around the shoulders. Older

walrus travels back again, far to the north. The

the northern

ÂŠ

Adult males

water. Otherwise, walruses are a cinnamon-

follows the edge of the

July.

look almost naked, with prominent

males appear to be pink shallow water along the

lives in

June and

the

more before the new coat grows. At

lumps on the

Floating

among

first

follow, losing their short, bristly hair a

its

body weight.

total

and breed.

Molting takes place

although they are not an important source of food.

to molt

and haul out onto

ivory,

and

Alaska alone.

an excessive number of

recent years.

younger animals form small parties of about 20, used

stopping to rest at traditionally

sites.

The

will

When

males compete with each other to stay nearby,

cradled

each one seeking to take over a whole group to

chest, or the

himself.

The

bulls

move around

displaying their tusks, whistling

above water, and making a noise too. Each bull

from

his

lot

nearest major

rival.

Like other

bull

icy seas.

submerged on an

mother's flippers, held close to her

young walrus can

grip the skin of it

floe.

along.

some of

the smallest walruses.

35 percent fat and also

with

0 percent of

bulls

remain

slip into

whom

Stomach Stones kinnipeds of several species, including the walrus, often have

the

mate

the

After mating, the fertilized

stones

their

stomachs. The stones are smooth, rounded

pebbles, sometimes weighing

pound (0.45

kg) or

in total.

egg remains dormant inside the female for

Some

about four months, then begins to develop

swallow stones, but

normally Pregnancy

suggested that padding the stomach with stones helps keep the

some 16 months

lasts a further year, a total in all.

Therefore, females

cannot produce a pup every

year,

and pups are

born at least two years apart, longer

the case

can be as large as tennis it

bails.

unlikely to

likely,

the stones act as ballast and assist

the animals dive.

Pups weigh about 140 pounds (60 kg)

when

they are born. At that time they have pale fur

with dark flippers. Mothers look after their carefully

â&#x20AC;&#x201D;

with far more devotion

be accidental.

from being too buoyant. Buoyancy makes in

sometimes

their

preventing the animals it

harder to dive and stay

the stomach helps counteract the

buoyant effects of blubber and any

Caring Mothers

Nobody knows why walruses

animals from feeling hungry during long periods without food. More

underwater. Carrying stones

of older mothers.

young very

ice

The Hudson Bay

population has

marine mammals, the walrus

produces milk that

Two North Hudson

Bay walruses, half

Small males stay

with the females. The females

dark and

and

and most successful

water to select a

may be

mother's neck as she swims, towing

its

clicking

the pup goes to sea,

spaced a safe distance

out of the way, and only about the biggest

in its

constantly,

of underwater

ÂŽ

help feed the orphaned offspring of other

females.

air

remaining

the lungs

when

interesting that crocodiles also carry stones in

stomachs and use them to cancel out the natural buoyancy of

their body, helping

them

stay underwater. Fossil plesiosaurs (large

extinct marine reptiles) often have shiny pebbles

where

their

the position

stomach would have been.

than sea lions show. For example, they do not leave their

pups

for long periods

and sometimes

MAMMALS

SEA

The pups grow well on

rich in proteins.

may

still

be taking milk from

but

it,

mother three

their

years after birth, although they are capable of

feeding on normal food long before then. They are normally fully

weaned

Young females tend

year.

about two years

begin to sprout at about one

old. Their tusks

to remain

their

mother's social group, but males wander off after a year or two.

mature

at six or

Females become sexually

seven years

Males take

old.

longer to mature, at eight to 10 years, but

not be able to breed successfully

with the big old males

until

grown, which may take

will

competition

they are

fully

5 years.

Traditional Targets

The walrus has played an important part and

native folklore

traditions for

years. For centuries

meat, for

and

oil,

making

little

was

and

for useful

and

effect

tents.

its

tough hide Such hunting

on the populations, so

carried out using

and from small

thousands of

has been hunted for

sled covers

probably had long as

ivory

hand weapons

boats. Hunters probably killed

no more walruses than other predators, such killer

whales and polar bears. However, major

exploitation by Europeans

began

the 16th

century and devastated the populations, particularly in the

North Atlantic.

the 19th

century more than 10,000 animals were taken

each year from parts of the North population alone. As a

became

extinct

retreating to

result,

many

more remote

its

Pacific

the walrus

former haunts,

places

where

could

not easily be reached. Protection by the

Americans

1909, followed by the Europeans

and 50 years

later

slow recovery

by the Russians, enabled a

numbers to

a present-day total

of about a quarter of a million. to

5,000 are

native people. if

clam

taking

legally harvested

each year by

The number may be sustainable

fisheries

away

Around 10,000

do not

vital

also expand,

hence

food supplies for the walrus.

walrus color)y on Round Island, Alaska. Despite

associating in

huge groups, which can be several

thousand strong, walruses are not very sociable animals.

SEE ALSO

Bear, Polar 2:84

SEA

MAMMALS

Monk

Hawaiian Seal

Monachus schauinslandi

Hawaiian Common name Scientific

Hawaiian

seal

name Monachus schauinslandi Phocidae

Order

Pinnipedia

Length:

10%

5-8. 2

(2-2.5 m). Female about

islands.

adapted

warm

to the is

They are not particularly well

climate, however, since their

almost as thick as that of polar

As THE HOT MIDDAY SUN

longer than male

are tropical seals that live only

on a few small

blubber

Family

Size

monk

monk seals

BEATS

dowfi relentlessly on

the sandy beaches and surrounding waters of

Weight 330-660

lb (1

50-300

kg).

monk

the northwestern Hawaiian archipelago,

Female heavier than male seals

Key features Completely

tropical seal, but with

obvious anatomical adaptations to climate; adult coat silvery gray

cream

and

belly, throat,

and yellow as

brown a red

or green tinge from algal growth on fur; pups

born with a black coat,

lost at

lie

cooling

on back with

sometimes has

seal ages;

Some

warm

chest; turns

can be found resting along the shoreline.

edge to allow

close to the water's

waves to wash over

their bodies, while

others seek shelter from the scorching sunlight. Every so often the animals take a dip in-the sea

I in

about 6 weeks

an attempt to refresh themselves.

| Habits

Adults usually

groups sometimes

solitary;

form on beaches, but

for favorable conditions

rather than as form of gregarious behavior;

feeds at night, spends majority of the day resting

on beaches; may disperse throughout

range, but not migratory

Breeding

pup born

Single 1

mature

unknown. May

Despite being a completely tropical the true seal family, Hawaiian

4-8

live

years,

Keeping Cool

| I

males

Diet

Reef-dwelling invertebrates and

fish,

including lobsters, eels, flatfish,

and octopus

they rest for most of the day, sometimes

breeding season

their

cool,

wet sand. They spend

a lot

metabolic rate and body temperature.

Much is

Distribution Found on islands northwest of Hawaii Population: 1,200-1,500;

of time sleeping, since inactivity helps lower

Sandy, tropical beaches and shallow lagoons

CITES

habitat. Instead,

25-30 years

Males roar

Status

warm

physical adaptations to a

days; females

Voice

Habitat

have

seals

almost the same amount of blubber as their

wallowing in

member

monk

polar counterparts. They also have no apparent

after gestation period of

1-12 months. Weaned

sexually

| | |

of the prey of Hawaiian

hidden during the day, so

monk

seals

at night that

the animals are most active. As nocturnal feeders they cannot

lUCN Endangered;

rely

on sight to find food,

but instead use their long, sensitive whiskers to

detect prey. They feed on a wide variety of

organisms, including lobsters,

The

diet of the

Hawaiian

with the seasonal changes

abundance of prey foraging

items.

eels,

monk in

and

flatfish.

seal varies

availability

Most of

and

their

carried out along the slopes of the

coral reefs at

depths of about 230 feet (70 m),

but they can dive to more than 1,600 feet

(500 m). By slowing their heart rate

SEE ALSO

Seal,

Northern Elephant 3:32;

Seal,

rate

down

â&#x20AC;&#x201D;the normal 55 to 120 beats per minute â&#x20AC;&#x201D;they are

fewer than 15 beats per minute

Crabeater 3:36

seals.

SEALS AND SEA LIONS HAWAIIAN MONK SEAL

able to stay underwater for up to 20 minutes. Fifteen beats per vital

minute

just fast

enough

for

organs such as the heart and brain to get

enough oxygen while the Hawaiian primitive.

monk

seal

submerged.

and

pelts as they lay basking in the sun.

was

so small that

began to

was

respite

have been their home: They

military activity in the

structures that are

ago.

in fossil relatives

Monk

retain several

primitive than those

from 15

of the pinniped order

members

and are sometimes

Second World War once

Today the population

estimated at

somewhere between 1,200 and 1,500 individuals,

making Hawaiian monk

second most threatened

referred to as "living fossils."

caused by

shortlived. Disturbance

again caused their numbers to decline.

million years

seals are the oldest living

However, the

reestablish themselves.

that the remote islands of the Hawaiian chain

found

Soon

was no

remaining seals a chance to recover, and they

the 15 million years

still

seals the

seal species in

the

world. Most of the islands they inhabit are

ÂŠ

protected within the Hawaiian Islands National

After the main islands of Hawaii were colonized

Wildlife Refuge, but three are also inhabited by

monk

restricted to the islands of the

the sedentary Hawaiian

The beaches of the

monk

islands

and

seal,

which

extremely sensitive to disturbance, became

are the ideal location for

seals to rest

now

Sensitive to Disturbance

by humans, the Hawaiian Lonely sandy beaches

oil

longer profitable to hunt them. That gave the

seals are in fact quite

for hunters. In the early 19th

century thousands were slaughtered for their

the population

They have remained almost

completely unchanged

were easy targets

and

atolls

Leeward chain.

small, isolated oceanic

were

free

from

terrestrial

humans. One of the main threats to

monk

sites are

the seals areas

predators, and without disturbance the seals

tide.

from large sharks, their

were able to

abandon

main predator.

inactivity

and

relative

tameness meant that they

sometimes give

disturbed,

birth in unsuitable

where pups can be washed away by the

give birth, offering safety

thrive. Unfortunately, their

high up on beaches; but will

disturbance

mothers. The preferred birthing

seal

It is

leaving

not

unknown

their

them

mothers to

for disturbed

pups before they are weaned,

to die of starvation.

Other threats to the species include a lack of food resources

entanglement sharks,

and the

due to commercial

fishing nets, predation by

effects of

seals are also at risk

behavior attack,

fisheries,

marine pollution. The

from "mobbing,"

mating

which groups of males chase,

and sometimes even

when

kill

trying to claim her.

not actually

killed,

she

female

the female

may be

weakened by wounds and vulnerable to shark attacks.

When

there are greater

numbers of males, the problem

enhanced.

MAMMALS

SEA

Northern Elephant Seal

Mirounga angustirostris

The northern elephant seal

one

of the largest of the world's seals, easily recognized

snout

inflatable

Common name Scientific

Northern elephant seal

name Mirounga Phocidae

Order

Pinnipedia

in the adult males.

most other seals and sea

angustirostris

species has suffered

lions, the Family

by the drooping,

severely from unregulated exploitation in the past. Size Length: male 13-16.5

female 6.5-10

(4-5 m); (2-3 m)

Weight Male 2-3 tons

Northern elephant seals spend more time at sea

(1.8-2. 7 tonnes): female

1,300-2,000

Habits

than most other pinnipeds: about 10 months of

(600-900 kg)

every year

Key features Huge almost

all

other seals, brown

Spends most of

all

90 percent of

over

which

time at sea; occasionally

its

Single

pup born

months

implantation). sexually

8-9

after gestation period of

(including

mature

years.

May

about

live

up to 20

Diet

Habitat

years, but

males

last

enormous. Such

up to two hours, but

so,

the average dive time and depth are

greater than for most other seals.

midwater; also some

There

fish

Cold coastal waters

lives in

Mexico

are, in fact,

species of elephant

subantarctic waters, occasionally turning

scattered locations across the Indian

Ocean and South

Population: about 100,000-150,000

two

The southern species {Mirounga leonina)

seal.

Distribution North Pacific coasts of North America from

Status

to 5,000 feet (1,500 m),

and only go down about 1,600 feet (500 m).

and slow-moving

California to northern

general.

normally the seals dive for about 20 minutes

Even

Mostly squid caught

down

deep dives may

Bellows and roars

small sharks

males at

usually fewer than 12

Voice

spent underwater,

where the water pressure

4 weeks; females 5 years,

time

their

also not typical of seals

occasionally

2-3 months delayed

Weaned

Moreover, elephant seals dive very deep,

hauls out to rest on rocky islands and beaches

Breeding

the case of females. About 80 to

seal with bent, floppy nose; unlike

Pacific. Its distribution

does

not overlap with that of the northern elephant but otherwise the species are

seal,

similar.

Segregated Males tend to disperse widely at sea to feed,

living

alone for most of the year. They travel

farther north I

{

into the Pacific

than females. Segregating the sexes

way

SEE ALSO

Seal,

Hawaiian Monk 3:30

such a

midwater,

often luminescent species that can be seen even

the darkness of deep water. The seals also

take small sharks and slow-moving

avoids competition for food. Elephant seals

feed mainly on the squid they find

in ;

and farther out

fish,

which

SEALS AND SEA LIONS NORTHERN ELEPHANT SEAL

ÂŠ A young male

they find

northern elephant seal.

seals

Young miles are

themselves.

aggressively prevented

match

from breeding by the

taken by great white sharks and

dominant

bulls until

have

for

about 12,000 miles (20,000 km). They gather

shallower coastal areas. Elephant

little

December on sandy and pebbly beaches around

to fear from predators

fully

grown elephant

seal

various islands along the California coast (and

any creature, but youngsters may be

Normally, carnivorous

killer

whales.

mammals have

at a

few

sites

on the mainland) to

harems and mate. The

bulls

set

compete with each

other by showing off their huge bulk. They rear

they are at least eight

shorter intestine than herbivores, buL the

up and bellow

years of age.

northern elephant seal has a longer intestine

chests crashing to the ground again. They also

than any other mammal.

One was measured

662 feet (201 m), which stretched

40 times

its

own body

longer than a typical

more than

length and 20 times

human

gut.

Each year northern elephant seals migrate

fiercely,

inflate their big

impressive. fights,

before bringing their

noses to become even more

Sometimes they engage

but avoid doing so

such a contest both males

and chests high

the

air

will raise their

and wrestle

to their traditional breeding beaches,

necks together, attempting to

completing a round-trip migration that totals

downward

stab at their

physical

possible. During

make

heads

their

opponent with

their big

MAMMALS

SEA

canine teeth. Raking the neck with the teeth

abandoned them, the pups

often opens long gashes, but the skin of an

feeding for a

elephant

wounds

neck

seal's

so thick that such

are rarely a danger to

life,

The

summer

they do leave impressive scars.

The dominant

number

â&#x20AC;&#x201D;adult males doing so as

Some

mate with the

largest

sometimes as many as 100.

of the males stay onshore, continuously

and without food, season

until

the end of the breeding

February or March

â&#x20AC;&#x201D;a

sand

may be

offers a

little

protection from the sun.

most

do, they shed the outer layer of

same

The

time.

comes

hair

animals a sorry sight while their

new

coat

no dense

the females give birth

sea lions. Instead, elephant seals (and other

that found

layer of

fur seals

to their single

pup

members

and provide

with

thick layers of fat (blubber) to insulate their

milk for up to four

bodies against the cold water

They might

easily get

sunshine was

not go to sea to feed.

come ashore

Instead, they stay

summer

close to their pup,

damp

rich milk

but do so

then giving

air

when

much

of the

usually bathed

come ashore

winter,

live.

summer

the

during the period they

fog, screening the animals

and

which they

to molt. However, for

of the sun. They

derived from their fat supplies.

warm

overheated

the California coast

own

and

of the true seal family Phocidae) have

weeks. During

off

The new growth consists only

into place.

of short, bristly hairs; there

her offspring,

that the

one by one

woolly underfur

milk,

its

unusual:

with ragged patches of skin, leaving the

from the heat

again to breed,

the weather

bad,

temperatures are low.

Females may be capable of breeding only

Converting fat to

seal

late as is

months. Meanwhile,

feeding

back.

their skin at the

early

time of over three

lactation they too

ÂŠ An elephant

mammals

other

grows

total fasting

throws sand over

elephant seals

Instead of losing their hairs

bulls get to

of females,

for themselves.

on land to molt

seals haul out

August. Molting

Enforced Fasting

Then they too go

or more.

and begin to forage

to sea

although

month

stay ashore without

means

three years after they are born, but usually

that a typical female

maturity.

may

anyway

lose nearly half

her body weight

takes about four or five years to reach sexual

Males take longer to mature and

are prevented

older and

dominant

from breeding by the

bulls until

they are at least

before she returns to the sea to feed.

eight years old. The stresses of breeding and

Meanwhile, the pup

holding territory on shore while also fasting for

will

have grown from a

birthweight of about 100 pounds (45 kg) to

three

more than 300 pounds (136

more than

kg).

months 1

are so great that

few males

live

2 years.

Toward the end of the suckling period the females later.

will

mate, then go to sea a few days

Development

of the fertilized

egg

arrested for a couple of months. The

then implants

itself

womb

a gestation

Targets for Exploitation Elephant seals were ruthlessly exploited 19th century for their blubber, which

melted burning

down in

make

lamps.

oil

the

was

for lubrication

big elephant seal

and

yield

pup

substantial sum. Over a quarter of a million

born almost exactly 12 months after the

one. At birth northern elephant seals have

a black coat, which

silvery hair.

soon molted and replaced

After their mothers have

SEE ALSO

Seal,

seals

up to 85 gallons (386

had been

1860s, As a to have

Gray 3:42; Monkey, Proboscis 4:70

killed for

result,

become

of fine

for

might

period of eight to nine months, so that the next

last

embryo

into the wall of the

and develops normally through

oil,

worth

the trade by the

elephant seals were thought

extinct

California waters, but

seem

there also

few

to have been a

remained on small islands

survivors.

Some

off Baja

However, reducing the population to

California.

such low numbers meant that present-day elephant seals have

all

come from

ancestors. That could prove a problem

future

â&#x20AC;&#x201D;the population being

few

relatively in

the

less resistant to

disease, for example. Elephant seals have

benefited from protection by Mexico and the

United States

the 20th century, and numbers

steadily increased to

more than 100,000 by the

1990s. Elephant seals have

almost

now

recolonized

the areas from which they were

all

eradicated

earlier.

Occasional stragglers are

now

seen as far away as Hawaii and Japan, and north to Vancouver Island and Alaska.

Big Nose!

he huge nose or proboscis of the adult elephant seal has nothing to do with

an improved sense of smell. Instead,

showing

for size

when

off.

The nose grows to

full

the males are mature at an age

of about eight years

and becomes even

larger in the breeding season.

almost

like a

droops,

small elephant's trunk, so

that the nostrils point

downward, and the

end overhangs the mouth by up to 12 inches (30 cm). The strange organ can be inflated by

blood pressure and a buildup

air inside,

so that

forms a large

cushion on top of the animal's snout. The skull

specially

shaped and enlarged to

accommodate the muscles used the proboscis. a resonance

In its

move acts as

chamber, magnifying the

bellows and roars that

make

inflated state

bull

elephant seals

to intimidate their rivals on the

breeding beaches.

ÂŠA

California

male threatens

rivals.

During the

breeding season males compete with each other for mates, and fierce displays of strength are commonplace.

SEA

MAMMALS

Crabeater Lobodon carcinophagus

"Crabeater" Common name Scientific

Family

Phocidae

Order

Pinnipedia

carcinophagus

specialized teeth that allow

smaller crustaceans

Length: 6. 5-8. 5

Size

Weight 440-660

brown teeth

consume

ice

follows the seasonal advance and

color with variable

sides; coat

summer; long snout;

fades to

specially ridged

cheeks; no external ears; often

retreat of the ice.

feeding on

krill,

has

become adapted

small shrimplike crustaceans

that form a major part of the plankton

polar

scarred from attacks by leopard seals and

waters. The seals have a specially modified

fights with other crabeaters

Habits

Male

female after she has given

joins

when pup

dentition that includes the

possessed by any carnivore. The lower and

weaned, male mates with

are usually solitary or found

most complex- teeth

birth;

female, and family group disbands; crabeaters

upper teeth have long, sharp prongs that

small groups,

when

together perfectly, so that

but larger aggregations can occur

the

closed, there are only tiny spaces

Breeding

Single calf born after gestation period of

Weaned

implantation.

mature food

3-6

availability.

average

14-21 days; sexually

years, often

May

live

depending on

up to 40

fit

mouth

between

months, probably including period of delayed

them.

When

the seal takes a mouthful of water,

the teeth act as a sieve, leaving the animal with a

mouthful of food. The teeth therefore

years, but

function

about 20

the baleen plates of filter-feeding

whales, such as the blue whale. Voice

Snorts, hisses,

frightened;

and blows through nose when

deep groaning sounds produced

while underwater

Success at a Price

Diet

Krill,

Habitat

Stays close to the pack ice of the Antarctic

other invertebrates, and small

fish

Crabeaters are the most abundant of

total retreating pack ice of Antarctica

Status

Population:

may be

over 10 million. The

world's most abundant seal

all

the

world's seals. Population estimates suggest that

Distribution Circumpolar, following the advancing and

numbers

lie

somewhere between 7 and

14 million individuals. After humans they are probably the most abundant large earth. Living

among pack

the

krill

that

mammal on

they can feed on

ice,

not easily accessible to their

competitors. The large baleen whales, for

example, have to feed

The environment inaccessible to

more open waters.

remote and

humans. As

relatively

a result, crabeaters

are not generally exploited, which

may

contribute to their abundance. Sadly, the

success of the crabeater seal

also partly

to the rapid decline of baleen whales.

whales were severely reduced

due

Many

numbers

during the 20th century owing to excessive

SEE ALSO

Seal,

Leopard 3:38; Whale, Killer/Orca 3:62; Whale, Blue 3:98

krill

â&#x20AC;&#x201D;strained from sea water

of the Antarctic, drifting through the sea

(200-300 kg)

markings on

ring in

The crabeater seal inhabits the extensive pack

floes as Slim seal; silvery gray

white

actually has extremely

(2-2.6 m). Female

generally larger than male

Key features

a misleading name, since the crabeater

seal does not feed on crabs.

Crabeater seal

name Lobodon

â&#x20AC;&#x201D;much

SEALS AND SEA LIONS CRABEATER SEAL

hunting and

left

a plentiful supply of

krill

support increasing numbers of crabeater

As true

seals,

external ears

and cannot

pull their

However, they are amazingly agile

known

ÂŠ A crabeater seal on an drift

ice floe.

on the

rests

The seals

floes,

diving

into the cold waters that

surround them to feed

seals.

snow and

ice,

hind flippers lions do.

when

and have been

(25 km/h). They look almost comical as they

to side

head held high, swinging from side

time with the

pelvis,

while the hind

flippers are held together off the

Unlike

some other

off the Antarctic's

crabeater

breeding season the seals can be found

female

joins the

just

males and predators. The male takes care of the

with her

when

small

waiting to mate

the pup has been weaned.

the

male moves too close to the female or her pup, the female

and female remain as

Most

weaned, the male

a pair.

two weeks,

separate.

mate seal

face

will react aggressively, biting his

and neck. Once the pup

will

not a colonial breeder. During the in

not always the

and the pup from other

actively protects her

within about

ground.

species of seal, the

abundant supply of krill.

father of the pup.

female and pup because he

to reach speeds of 16 miles per hour

sprint, their

and pup. However, the male

before or soon after she has given birth and

crabeaters do not have

forward to walk as fur seals and sea

traveling across

Mating occurs

which the

after

seal species are

the water, but mating

thought to occur on the

pair

known

the crabeater

ice floes.

family groups consisting of a male, female.

War Wounds Pups and juvenile crabeaters are at attack by leopard seals.

down

scars running

Many

from

risk

adults have long

their bodies as a result of

Some

predatory attacks by those fierce animals. individuals

may even bear

attacks by

killer

the scars of failed

whales, which hunt

crabeaters of

all

ages. Older male

crabeaters are often heavily scarred

their face

and neck as

of fights with males of their

own

or another,

a result

and females

species.

One way

most adult

pelts

are so scarred they are of little

commercial value.

The international ban on whaling has allowed

some populations

baleen whale to recover.

Numbers seals

may

of crabeater

decline as the

ecosystem readjusts to the return of the krill-eating

whales.

addition,

commercial fishing of Antarctica's

krill

now

progress,

providing yet another competitor for that resource. The breeding success and

population growth of crabeater seals could restricted as a result.

SEA

MAMMALS

Leopard Seal

Hydrurga leptonyx

sharp canines and reptilianlike head give the

Its long,

leopard seal a ferocious appearance. Living up to Common name

reputation, the seal Scientific

name

the

main predator of the

Hydrurga leptonyx

Antarctic Family

Phocidae

Order

Pinnipedia

Size

Length: male 8.2-10.5

ft (2.

5-3. 2 m);

Weight Male 440-990

female 495-1,300

(200-450

distinct

kg);

(225-590 kg)

Large, slender seal with reptilelike

that

head

the sea leopard, the leopard seal

named because

that decorate

almost anything that moves.

will attack

its

and patches

of the spots

Unique as the only

coat.

pinniped that regularly preys on warm-blooded animals, the leopard seal

from body than most life

well adapted to

as a predator, eating almost anything.

its

Its

powerful jaws with wide gape; long

seals;

varied diet includes

canines and sharply pointed molars; long,

broad front sides

and

Once known as

female 7.8-11 ft(2.4-3.4 m)

Key features

and

flippers;

penguins, and other sea birds.

dark-gray back, paler

silvery underside; variable spots

squid, octopus, fish,

krill,

on other

habitually feed

addition,

will

seal species, particularly

shoulders, throat, sides, and stomach

crabeater seals. Although the majority of seals Habits

Solitary,

than

ferocious creatures: rare to find

on an

ice floe

other than

attack

the leopard seal could be described as the

(including a probable

males at 4 years.

May

the wild, rarely kept

live

2-month period

Weaned

weeks; females sexually mature

Krill

years

seals,

and squid

pack

unusually long for a true seal.

seal are

When swimming,

true seals propel themselves through the water

low droning sound made underwater

Antarctic

aggressive predator,

The foreflippers of the leopard in

captivity

and other crustaceans; penguins,

classes.

marine equivalent of the leopard on land.

at 3 years,

at least

age

all

about 4

Gargling, grunting, whistling, and birdlike chirps;

Habitat

will

Single pup born after gestation period of

months

Diet

older animals indicate that leopard seals

often found near penguin and seal colonies

of delayed implantation).

Voice

preyed on are young, fresh scars on the pelts of

breeding

season; segregated by age to different areas;

Breeding

by moving their hind limbs from side to side. contrast, leopard seals

long,

powerful strokes of their large foreflippers,

more and subantarctic waters, often near

swim with

like a

sea lion than a seal.

they are fast and agile

â&#x20AC;&#x201D;

the water

dangerous hunter

ice

even for the elusive penguin. Distribution Circumpolar distribution along edges of antarctic pack

ice;

found

all

year round and

System

seasonally on subantarctic islands; sometimes

Filter

along Australian and South African coasts

Armed with remarkably

long canine teeth,

sharply pointed molars, powerful jaws, and a

wide gape, the mouth of the leopard well suited to grabbing prey.

the crabeater seal, that can

The

filter

out

seal

addition, like

has complex cheek teeth

krill

from mouthfuls of water.

system enables

food source

to use an alternative

larger prey are unavailable.

A common

habit of leopard seals

prowl the waters beside penguin rookeries.

its

Leopard seal

SEE ALSO

Seal,

Northern Fur 3:14, Seal, Cape Fur 3:16

stiff hairs,

typical of

SEALS AND SEA LIONS GRAY SEAL

ÂŠ

Outside the breeding

seals.

Its

main function

to protect the skin

season gray seals haul

from being damaged as the animals heave

out on rocks or

themselves over rocks. The pups get

sandbanks to also molt

rest.

They

land,

mother's milk. Milk for three

The milk

to sea to feed herself.

the mother's

several weeks; the males

average of over 7 pounds

March to May,

own

fat reserves,

formed from

and she

about 55 percent

to develop

its

fat,

insulation before

loses

body weight

(3 kg)

each day. Seals produce very creamy

which

their

provided every five hours

changing their coat once

the females earlier.

weeks, without the female returning

a year. The process takes

molt

fat

many

years.

entirely of fish. daily of

The

poor, but even

appear to cope well and may gray It

seal's diet consists

takes about

live

for

almost

pounds

(5 kg)

whichever species are most abundant.

seals travel long distances,

and some have

turned up over 1,000 miles (1,600 km) from

where they were born.

milk,

enabling the pup it

the water. Their eyesight

blind seals

goes to

sea.

Friend or Foe?

Numbers

of gray seals rose steadily until the

By that time the baby fur has been shed, and

1960s, then nearly doubled

the pup weighs about 100 pounds (45 kg).

Fishermen began to complain that the animals

Toward the end of the suckling period each

cow mates

with one or more bulls and then

returns to the sea.

The pups are abandoned on

the open beach. They go to sea for the

first

10 years.

threatened their livelihood because of fish

they ate. Culls were carried out

of public opposition. fish, their

predation

In fact,

may

all

the

the face

although seals eat

actually increase the

time shortly after and must quickly learn to

numbers

feed themselves. Nonetheless, about 85 percent

other species that compete with

of pups normally survive to this stage.

However, gray seals can cause damage where

When

ashore, seals spend over 90 percent

of their time inactive. Their busy times are spent at sea, but

little is

known about

their behavior

of larger commercial fish by removing

them

fixed nets are set to catch salmon.

for food.

They may

also try to break into floating cages used to rear

captive salmon, causing fish to escape.

MAMMALS

SEA

Harp Seal

Phoca (Pagophilus) groenlandica

The Arctic harp seal has been the subject of major international controversy due to the harvesting of its attractive white

The harp seal

Common name Scientific

Family

Order

name

Harp

seal (saddleback seal)

Length:

North Annerica the

its

seal's

to the

rise

name

"saddleback seal." The harp seal frequents the

Pinnipedia

edges of the Size

markings have given

distinctive

Phocidae

harp-shaped band around

and back.

flanks

their skins.

so called because of the

characteristic

Phoca (Pagophilus) groenlandica

pups for

5, 6-6.4 ft (1

Weight 250-310

arctic ice.

ranges far to the north

.7-2 m) lb (1

Canada

the

summer months,

often

13-141 kg)

migrating over 3,000 miles (5,000 km) between

Key features Adults

gray with a black face and

light

its

bold, curved dark marking

summer

breeding grounds and

feeding areas.

on the back;

pups white Habits

Spends most of year

Fishy Diet at sea

along edges of

Harp seals eat mainly shrimp and small

arctic ice

Breeding

Single

pup born

February after gestation

period of 10 months (including 4 months

delayed implantation).

Weaned

10-12

caught near the surface

fish,

open waters.

However, adults may dive 500 feet (150 m) to feed on herring, cod, and other larger

The

fish.

days; sexually mature at about 5.5 years, but

often does not breed

May Voice

live

until

about 8

years.

Various barks, grunts, and growls;

Shrimp and small

Habitat

Open

big, sensitive

They make

30 years

fish, especially

number

eyes for locating prey.

of underwater grunts to

communicate with each

other, but are generally

different vocalizations recorded

Diet

have

seals

silent

capelin

above water except

colonies.

They

seas and edges of ice floes

distances from the

around

live

hummocky

crumpled,

at the

breeding thick,

and may

ice

travel long

open water by following

Distribution Populations based on 3 breeding areas:

Newfoundland, Jan Mayen

Island,

Sea, with animals dispersing farther north

Status

and White

and going

channels

the

Harp

They can swim

ice floes.

underwater and move

summer

Population: probably at least 3 million.

fairly rapidly

seals breed in three

Newfoundland, Jan Mayen

main

fast

on the

ice.

areas:

Island (east of

Abundant Greenland), and Russia).

the White Sea (north of

They assemble

large

numbers

in late

winter (February and March). The newborn seals are nursed

that their

cry

two

to three times a day on milk

more than 40 percent

weight

and

wail,

triples in less

and

their

fat.

a result,

than two weeks. Pups

mothers

call

to them, so

breeding colonies are noisy places. After 12 days the pups are abandoned and

left

to molt.

They then go to sea by themselves. The females

now mate and undergoes

disperse. Their fertilized

development before

SEE ALSO

Seal,

Harbor 3:40

egg

four-month period of delayed full

pregnancy begins.

SEALS AND SEA LIONS HARP SEAL

Controversial Cull Since about 1800 harp seal breeding colonies

have been heavily exploited to collect

easily

pelts,

from the white pups. The animals are

especially

approached across the

ice

and cannot

escape by diving into the sea. Pups are large

numbers by clubbing:

about 180,000 to be

for

known

killed in a

year off the

Newfoundland alone. At one time the

coast of total

killed in

has been

may have

population of harp seals

numbered up

to 10 million. However,

percent of

its

Concern

potential size.

became

severely reduced, perhaps to less than

for the

species grew, and public opinion turned against culling

and the apparently

Campaigns

methods used.

brutal

to stop the cull resulted

confrontations on the ice between sealers and

animal conservationists. The Canadian

government, anxious to protect the source of income for

locals,

traditional

refused access to

the breeding areas, even to aircraft and helicopters. publicity

The aim was to reduce adverse

and to keep opposing factions

apart.

Persuaded by public disquiet, European

banned the import of harp

countries in

1983. The ban sharply reduced the market,

but did not result off.

ÂŠ

The pure white fur of harp seal pups against the

white

snow is

a particularly appealing sight.

It is

not

surprising that feelings run high over the culling of pups.

months. The delay ensures

the seal hunts being called

Today about 50,000 pups are

similar

number from the White

7,000 from Jan Mayen. The

numbers

The

Sea,

culls

effect of a cull

taken

and about

remain

on breeding

not seen for at least five years, by

that the pups are born at one-year intervals.

which time another quarter of

Otherwise they would

will

arrive in midwinter, or

still

each year from the Newfoundland colonies, a

controversial. lasting a further six

seal skins

have been

killed.

a million

pups

Yet despite such huge

the males and females would have to find each

numbers being harvested, the harp

seal

other again to mate

population remains large. However,

many

about May. By mating

on the breeding grounds, males and females

people believe that

need only come together once

cruelty

a year.

Females become sexually mature at years old, (occasionally a

little

sooner),

five

until

they are

much

older.

numbers become reduced, however, they tend to breed at a

younger age.

wildlife, especially

young animals.

for local people

who

might otherwise

have to move to find work. There

densely crowded populations the animals do

not usually breed

should not exert such

the other hand, the industry provides an

income

and

males at about the same time. However,

also the

problem that the increased harvesting of

fish

humans may remove the food supply needed maintain large populations of seals of

by to

all

species, the harp seal included.

DUGONGS AND MANATEES â&#x20AC;&#x201D;he

curious

dugongs and manatees

are

members

What

a Sirenian?

no hind

the order Sirenia. They are descended from land

Sirenians have

animals that were distantly related to elephants.

modified to form large

They probably fed on aquatic vegetation some 50 to 60 million years ago. By

spending greater amounts of time

their tails

expanded

True "sea cows," they

munched in

about 40 to 50

waterweeds

estuaries.

disappeared, and

their

way through

the

million years ago. Later,

became

proliferated

less

abundant.

the big rivers and

new food

source.

Meanwhile, the dugong's ancestors remained associated with sea-grass beds and spread to other tropical oceans, leaving the

manatees to occupy the

relative, Steller's

Atlantic.

sea cow, evolved to exploit the

seaweeds of the cool waters of the North exterminated by overhunting

brown but

the mid- 18th century.

shallow seas and estuaries where they thick

and naked. They are

more than

live.

into a

the warm,

The

skin

weighing

body appears rather bloated,

a small car. Their

intestines,

50 feet (45 m) long. Such a vast gut

digest the

expanded

large animals, often

which can be up is

needed to

huge amounts of vegetable material that

sirenians eat, typically over

Manatees have

200 pounds (90

kg) each day.

peculiar teeth which, like those of

strong teeth helps

them cope with the

often gritty plants they feed on.

was

rather

muddy and

Dugongs have only

few

simple teeth, and the males have short tusks.

sirenian's

head appears sunk

into the shoulders,

with no neck. The front of the head

giant

Pacific,

tail is

elephants, are continually replaced from behind. Having

At that time the ancestors of modern manatees

developed special teeth to exploit the

their front legs are

The

flippers.

perhaps because of their huge

the shallow waters of the

as the climate cooled, sea grass Instead,

finally

form huge, propulsive paddles.

swards of sea grass found tropical Atlantic

and

broad paddle used to propel the animals

the water, the animals gradually stopped coming ashore. Their hind limbs degenerated

limbs,

has thick, fleshy

lips.

These muscular

pulling off mouthfuls of vegetation

material

backward

into the

sensitive, helping the

water

blunt-ended and

lips

and

are used for

stuffing the

mouth. They are

animal grope around

to select suitable things to eat.

search for food

also very

muddy

The animals'

also assisted by taste

on the tongue, and manatees

show

preferences for

buds

at least

some

over others. The

Who's

Who among

the Sirenians?

—manatees: 3 species

Family: Trichechidae

manatee (Trichechus Family: Dugongidae

—dugong;

cow (Hydrodamalis

sea

species

genus, including West African

Amazonian manatee

senegalensis):

gigas) extinct

lips typical

an Amazonian manatee tail

typical of

species of sirenian

They

pigi

earflaps,

quite good, at

underwater. However, they do not seem to be as

least

good

why

at detecting

low-frequency sounds, which

may be

they often do not recognize the approach of motor

boats,

sometimes with

lives

widely spread

the Indian Ocean. The three species of

manatee occur

along the tropical coasts of the Atlantic,

mouth

of the

Amazon,

of fat under their skin:

Florida

manatees gather

make

Few

make

their backs. Typically,

short dives to gather food underwater, usually

remaining submerged for

less

than a minute. They mate

the water and give birth to single young there.

only

mammals adapted

the sea and are the

to feed entirely

on marine

plants.

calf in a

freshwater spring.

the strongest social link in the sirenian world.

plants.

Humans

killer

whales large enough to

However,

oil,

meat,

their useful

and

skins

make them

vulnerable to attack by humans. Accidents are frequent,

Consequently,

sirenians have

all

numbers. They reproduce

and entanglement

sea

cow

now

extinct,

most of

numerous,

where they

its

at least

are

slowly, so their Steller's

and the dugong has become very

range. Manatees remain

around

strictly

been severely

populations cannot withstand heavy exploitation.

rare over

The infant-mother bond

power

stay farther out to sea.

reduced

places for the winter,

make an approach normally

may not have another

nowhere other than

warm

cooler waters.

long-distance journeys.

and sharks and

sirenian,

nets.

live

living in

too, particularly collisions with boats

for several years afterward.

without food

natural predators can tackle the thick hide of a

Mothers suckle their offspring for up to two years and

Dugongs

The Amazon manatee

do not normally undertake seasonal migrations,

Sirenians

Sirenians are slow, placid creatures that rarely travel far or

they

manatees

insulation for those

Relations with

water hyacinths and

the dry season. The accumulated fat also provides

Lifestyle

extensive beds of algae growing

a wider range

fat reserves to survive long periods

but occasionally

They are such slow movers that they often have

mud

mangroves. Manatees store large

bits of

and also along parts of the West African coast.

fast.

the sand and

including water outlets from electric

the

(3).

forms vast carpets

and brackish water, where they take

its

cow

Manatees are more often found

plants grow.

submerged

northern Australia, with small, scattered populations

of vegetation, including floating

uses

along the coasts of the southwestern Pacific and

Caribbean, around and into the

fresh

amounts

fatal results.

The single species of dugong

where the

sea

specialize in eating sea grass, a

also has nutritious roots buried

although their sense of hearing

Steller's

shallow, well-lit waters. Sea grass

both above and below

shows the

manatees: the biggest

was the

straplike plant that

and

of sirenians;

has been extinct since 1768.

eyes are small

(2)

(1)

displays the strong bristles

rounded

(T inunguis)

genus (Dugong dugon)]

Florida

fairly

and the Caribbean,

protected.

Steller's

SEA

MAMMALS

West Indian Manatee Manatees float gently

TTichechus manatus

shallow waters, munching on

foating and submerged vegetation. These large but harmless creatures do a Common name

West Indian manatee (Caribbean

manatee) Scientific

name

Family

Trichechidae

Order

Sirenia

West

Indian manatees

waters and large Length;

Size

2-1 5

ft (3.

job keeping waterways

free of weeds, but their reward

is to

motor

victims of collisions with

manatus

Trichechus

usefiil

boats.

occur around the coastal the West

rivers of Florida,

7-4. 6 m) Indies,

Weight up

and the coasts of northern South

tons

Annerica, (1 .2

They are sometimes regarded as

tonnes)

forming a northern and southern subspecies.

Key features sluggish,

grayish-brown tail

and no hind

Large,

and slow-moving creature: with paddle-shaped

in color,

limbs; skin

naked with

The former, based around

numbers about 2,000 southern subspecies

patches of green algae and a few scattered, bristly hairs;

Habits

Moves

blunt-ended head with

and

fleshy lips

slowly, floating

Single

young born

about

births.

year,

and diving

probably

â&#x20AC;&#x201D; up to

shallow

small family groups

after gestation period of

with long intervals between

Weaned at 2 years; sexually mature at May live at least 28 years, probably

animals generally gather

live

groups of

tolerate each other,

The

10,000 or so

â&#x20AC;&#x201D;are

the Caribbean and along

rest of

the coast of South America as far as

small, piggy eyes

water; often found

Breeding

thick,

spread over the

Florida,

to 3,000 animals.

alone, but

Brazil,

The

sometimes

or more. While they

six

manatees do not form

subordinate individuals.

dominant and

true social structure with

In fact,

the animals

may

8 years.

and leave the groups whenever

casually join

considerably longer

they

Voice

Normally

Diet

Aquatic plants, floating and submerged; also

silent

like.

They are probably drawn together by

an attractive resource, such as a plentiful supply grass

and other vegetation overhanging from

of food or stretches of unusually

warm

water.

riverbanks

Habitat

Estuaries, large rivers,

and shallow seas

Distribution Florida, Caribbean, and coastal waters of

South America as far as Status

Brazil

Signs of Affection Apart from the close association between

mothers and

Population: probably about 10,000-12,000;

interactions

lUCN Vulnerable; CITES

they

show

their offspring, there are

few

between manatees. Nevertheless,

signs of affection

gentle "kissing." There

and may indulge

also evidence that

manatees may leave scent marks on logs and

submerged

rocks.

underwater, but

The scent cannot be detected

may be

tasted instead. Such a

form of chemical communication

among in

mammals,

land

the water.

may

common

of course, but unusual

indicate that

make some

sort of social

But there

no sign of

manatees

arrangements

after

territorial behavior,

SEE ALSO

Dolphin,

Common

them

off obstacles

and

locate their prey.

their sense of touch: Their long

and the

flippers feel for the

bottom

long beak has

sensory hairs that grope

stiff,

around for prey

it is

threatened by deveiopments aiong the river banks.

7.5

Habits

often

seen of the five river doiphins. Like the others,

geoffrensis

Family

fin;

The Amazon dolphin

dolphin (boto, pink dolphi n)

of the

the soft mud.

3:68; Dolphin, Pacific White-Sided 3:70

river,

River Dolphins of the Unlike most other cetaceans, the neck

Amazon

bones of

single piece.

As a

dolphins are not joined

twisting

and turning through the dense tree trunks and

cetaceans, teeth.

Those

dolphins have

two types

the front half of the jaw are

pointed and conical as

other toothed whales.

molars. These

used to crush tougher catfish, crabs,

prey,

flat

rivers

Yangtze

(R minor),

(Pontoporia

river

blainvillei),

sonar to detect ancestor.

the back of the jaw the teeth are flattened

and look more

across the world from South America to

Uruguay. They are

vegetation of a flooded forest. Uniquely for

Amazon

olphins are usually thought of as ocean creatures, but

and even small

all

prey.

dolphin {Lipotes

which

river

proximity to

and

likely

humans. Despite

similarities,

dolphins

became adapted

came about

they

and many

may

all

teeth,

evolved

life.

some

river

systems

—the —are also seriously

tropical forests

The likenesses

in similar

conditions.

drowned

parts for their

making the eroding

rivers

soils.

flow more

Dams

erratically

also

pollution.

They are more

at risk than other

cetaceans because rivers

and

block off the dolphins'

navigation routes, so small groups

damages food

chains that support the dolphins' prey.

become

Such groups are vulnerable to

tend to be more polluted than open seas. The dolphins also

come

into

contact with sewage and

isolated.

charms. They are also hunted for meat and

extinction. Drainage for agriculture reduces

pollutants from factories

navigable waterways and can be lethal

and gold mines.

commercial fishing

oil,

nets.

ail

use

different parts

eyes and sex organs, which are valued as love

and can get trapped

and

common

not share a

to freshwater

as they

destroys the "sponge" effect of the trees,

local beliefs that

dolphins harbor the souls of in

La Plata dolphin

that different species of marine dolphins

threatened. The removal of trees

species, river dolphins

people, they are hunted

and the

turtles.

everywhere are threatened by their close

Amazon

vexillifer),

teeth are

dolphin populations are

more secure than some

freshwater

and China. The

the Plate River between Argentina and

small dolphins with a long snout

of the world independently

between the

lives in

Despite their

The dolphins' habitat

Amazon

live in

such as armored

Problems with People Although

some

India, Pakistan,

other species are the Ganges dolphin {Platanista gangetica), Indus dolphin

they can turn their

result,

them catch prey when

heads, helping

World

emnties the doinhins' seasonal flood nools.

SEA

MAMMALS

Whale/

Killer

Orca Common name

Killer

whale

(orca)

member of the

The largest Scientific

Orcinus orca

name

dolphin family, the killer

Orcinus orca

whale (or orca) Family

Delphinidae

Order

Cetacea

the top sea predator.

Hunting

groups, orcas will even attack giant blue whales. Length: male 17-29.5

Size

(5.2-9 m); female 15-25.5 ft (4.

whales are one of the most recognizable

Killer

5-7, 7 m)

cetaceans, familiar from their antics

and

bodies Striking black-and-white markings;

belly,

high

Habits

triangular dorsal

and gray saddle

fin,

up to 6

(56 km/h)

From

tail

fin. In

Social, living in a tight-knit family

6 feet

(1 .8

group or

swimmer; acrobatic and

tail

at the

gestation period of 17 months.

Weaned

14-18 months; sexually mature

Males may

up to 90 years

more than Voice

live

35-60

most recognizable

the

mature male

can be up to

â&#x20AC;&#x201D;the height of

tall

fin

triangular

tall,

man.

only half as

more curved shape. The

tall

and has

flippers are also

large, especially in males. Killer

whales have 20

12-16

years, females

the wild; rarely survives

few years

whale

killer

females the dorsal

slap

Single calf born about every 8 years after

years.

the

fast as a racehorse.

a distance the

feature of a dorsal

"pod";

Breeding

â&#x20AC;&#x201D;almost as

black on top, white on underside

surface, will breach, spy-hop,

mammal

35 miles per hour

ft (1 .8

male; broad, rounded flippers;

fast, active

fastest

sea, with sprints recorded at

patch; head rounded with no obvious snout; tall,

make them the

body

mainly black with white patch behind eye,

white cheeks and

with characteristic

black-and-white markings. Their muscular

3-10 tons (2.5-9 tonnes)

Key features

captivity

the Free Willy movies. They are very

large, heavily built dolphins

Weight

26 sharp teeth

both the top and bottom

jaws. The teeth are pointed, conical, and each

When

up to

2 inches (5

close,

they interlock perfectly, clamping

cm) long.

the jaws

in captivity

Varied, including complex, often pulsed, calls

other prey

in a

and

fish

vicelike grip.

Ssmall fish and squid to seals, turtles,

Diet

seabirds,

Habitat

Open

and even other whales

Not So Deadly

sea to coastal waters; estuaries; often

around

ice floes in polar

Distribution Every ocean

Killer

whales are formidable hunters and gained

their

name from

waters

the world, from polar regions

them

18th-century whalers

who saw

attack other whales and believed that

to equator

they would also eat humans. This belief lasted Status

Population: 100,000;

lUCN Lower

conservation dependent; CITES

II.

Risk:

Widespread

and quite numerous

the 1960s,

until

whales more

when people began

closely.

Despite their reputation,

there are no records of killed

by a

killer

the more kindly Killer

to study

humans

whale, so

name

ever being

some people

prefer

of "orca."

whales are one of the most widely

distributed animals

the world. They

live in

every ocean and have adapted to both the

icy

conditions of the Antarctic and the warm, equatorial seas. However, individuals

do not

appear to migrate between them as some

SEE ALSO

Dolphin, Pacific White-Sided 3:70

One

cold, polar waters.

see orcas

de Fuca Killer

whales are the

top sea predators. They

and eat almost

will catch

any type of preyâ&#x20AC;&#x201D; from seals

and

turtles to other

common

whale do. They are more

the wild

of the best places to

the waters of the Juan

and San Juan

Strait

between

Islands

Washington State and Vancouver

Island, British

Columbia, Canada. Killer

whales

identified,

live in social

groups known as

one mature male,

several

whale have been

killer

each with different

There are residents, transients

social habits. (or

and offshore animals. Residents stay

relatively small

large

home

and

range. They tend

communicating to each other

to be very noisy,

with frequent

calls.

They hunt using

echolocation and feed mainly on

mature

wanderers),

family pods, usually of five to 25 animals,

have a

"pods." These consist of up to 50 animals, usually

Three types of

fish

and squid.

young

They are

one to

whales. However, they

females, and

tend to feed on locally

stable, tightly knit groups, with animals staying

seven animals. They roam over a wide area and

abundant resources and

with the same pod for their whole

are quieter, using stealth to hunt sea

this

of both sexes.

life.

such as

can affect hunting

techniques

body

and even

size in different

parts of their range.

Transient orcas

Group

Dialects

Animals

in a

calls,

some

which may serve to

identify the

group to other pods. Each pod has a

distinct

The

dialects are so distinctive

that by listening to the

researcher can

tell

seals, sea lions,

mammals

and other dolphins.

calls,

even a

human

which pod an animal

open

sea,

much

farther

and probably eat mainly in

large groups of

away from the fish.

from.

Killer

whales

the

coast,

They seem to stay

25 or more, communicating

with each other frequently and

dialect, using a characteristic pattern of

repetitive sounds.

smaller pods with

Offshore orcas spend most of their time

pod communicate with complex

live in

will

noisily.

catch and eat almost any

type of prey. They have been recorded eating over 100 species of animal, more than any

SEA

MAMMALS

Other cetacean. As well as will

and squid, they

fish

eat seals, dugongs, turtles, penguins, gulls,

and even other whales more than 10 times their size.

When

They hunt cooperatively

lips

and tongue.

a team, like a

herd salmon

by making noisy

and slapping flippers

calls

Killer

whales are

coast of Patagonia,

social animals that live in

Argentina, snatches a sea

tightly knit

lion for its meal.

known

groups

as "pods."

killer

whale pod

surfacing in Canada.

Often the whales will

work together

hunt

prey, such as salmon,

trapping shoals between the

SEE ALSO

pod and

Wolf, Gray 2:54

the shore.

ice for seals.

killer

whale's

and

watched

First,

it,

the whole group

then

all

group of

they spotted

few

swam

slid off

whales could catch

wave

rapidly

it.

ice.

wash over the

at such a sharp angle

into the sea

together dived under the

loose ice floe, tipping that the seal

When

carefully for a

Their dive caused a big

one

antarctic waters

whales, their heads poking out of the water,

frightened bunch

where the

Such an example of

cooperative behavior suggests that

killer

whales

are very intelligent creatures, capable of

;

the whales go to

problem solving and coordinating

great lengths to catch

as a

favorite foods,

researcher

toward

the

whale off the

fish in a tight,

sea lions are

have been known to hunt seals by tipping them off ice floes.

minutes.

eat them. Seals and

killer

whales

surface, trapping the

(

whales launch

Then, using their front

one, they watched

killer

they wriggle back into the sea to eat

flippers,

scanning the

their

on the

before lunging

Ocean

and on the Crozier

themselves onto the beach to seize baby sea

their victim. Killer

catch different prey. will

parts of Argentina

lions resting there.

wolf pack, and use different techniques to

They

water:

Islands in the Indian

they attack large whales, they

tend to bite pieces off their

them. Prey animals are not even safe out of the

group for the benefit of

all.

their actions

WHALES AND DOLPHINS

Killer

interference causes

species of whale,

many

deaths.

whales are hunted, although in

the past.

less

human

Some

Studying

killer

now

killed

5,537

killer

whales.

A few

have also been caught for exhibition aquaria

most

killer

whales only

live

for a

rcas in the

waters around Vancouver Island

Canada, have been studied

Some have

for

many

years. Individual animals

distinctive nicks

and scars on

their bodies.

recognized. By following particular animals from birth, recording their family histories, habits, and interactions with other orcas, researchers are learning

more and more about the complex

Salmon Stealing

fishermen,

who

will

conflict with

sometimes

kill

them

they

Other threats include boat

believe that they are taking valuable fish. In

Alaska

salmon

killer

whales have learned to

directly

from fishing hooks.

steal Fish

farms

can also cause problems. Intensively farmed fish are a source of diseases,

and pesticides used to

control fish lice can get into the

fins.

The shape of

the gray saddle marking often varies, enabling individuals to be

previously misunderstood creatures.

whales also come into

Columbia,

spectacle for millions of visitors each year.

Killer

in British

few

but offer a fascinating and educational

years,

Whales

can be identified by the different shapes and sizes of their dorsal

orcas

major

â&#x20AC;&#x201D;over 150 since the 1960s. Once

captivity,

Killer

than

the years between 1938 and

1981 Japanese, Norwegian, and Russian

whalers

WHALE/ORCA

whales have no natural predators; but

many other

as with

KILLER

food chain.

traffic

and

killer

whale

also particularly vulnerable to pollution,

which

underwater noise from engines. The

affects

its

prey and can lead to the

accumulation of dangerous substances whales'

own body

tissues.

the

lives

of these

SEA

MAMMALS

Long-Finned

Whale

Pilot

One of the most

Globicephala melas

sociable whales, long-finned pilot

whales are always found

groups. Because they stick

mass

together, they are susceptible to

Common name Scientific

name

Long-finned

pilot

hunters find

whale

easy

to kill

them

in large

Globicephala melas if

â&#x20AC;&#x201D;the long-

Family

Delphinidae

There are

Order

Cetacea

finned and short-finned. Both look very similar:

Size

Length: male 13-25

whale

species of pilot

medium-sized whales with a bulging

black,

(4-7.6 m); female

two

forehead and a distinctive wide dorsal scientific

name

The

fin.

of the long-finned pilot whale,

Globicephala melas, means "black round-

female about 1-2 tons (0.9-1

Key features Medium-sized

tonnes)

dolphin; black, dark-brown,

or gray-black, sometimes with gray markings

behind eye, on chin, and behind dorsal

fin;

head."

One

apart

the length of their pectoral

few ways

of the

the

two

of telling the fins,

However,

flippers. Their teeth are also different.

species are rarely confused, since they

do not tend

to be

Long-finned

pilot

found

the

same

place.

rounded head with bulging forehead; dorsal fin

wide, thick, curved back, and set toward

front of body; flippers long

be up to Habits

25%

and pointed: can

body length

Highly social: swims slowly

water, but

Breeding

One

calf

lifts tail

rarely leaps

from

born per year after gestation period

of 15 months.

at 2 years; sexually

mature at

live

over 60 years

Diet

Mainly squid;

Habitat

Offshore, prefers deep water; occasionally

comes

establish

10 to 50 animals, but

into coastal or shallow waters to feed

waters of

Widespread and

fairly

groups, sometimes

some herds can number

several hundred. There are usually

shoaling fish

all

seas

Southern Hemisphere Status

whales are highly sociable.

bottlenose dolphins. Groups usually consist of

and whistles

all

tropical waters.

keeping company with other cetaceans such as

Clicks

Distribution North Atlantic and

pilot

They are always found

Voice

some

warmer

Keeping Company Long-finned

above surface

Weaned 8 years. May

of temperate to subpolar regions, while the

large groups;

often seen "logging" or lying horizontally

water apparently asleep;

whales prefer the cool waters

short-finned prefer

many females

about twice

as males. Males have to

dominance

for mating rights,

common

and

their

scarred bodies are evidence of such contests.

Groups swim slowly and often

travel in

formation, with bands of animals moving

long lines abreast of each other and separated

by a few feet. The arrangement probably

maximizes their chances of spotting

main food mackerel,

prey. Their

small squid, but they also like

whose

seasonally. Pilot

shoals they follow around

whales

will dive for

food. Each

dive lasts about 10 minutes. They usually dive

down about 100

200

feet (30 to

60 m), but

deeper dives can reach 2,000 feet (600 m).

SEE ALSO

Dolphin, Bottlenose 3:72

strandings,

numbers.

and

WHALES AND DOLPHINS

Stranded

whole groups of whales toward shallow, sandy

Strandings on sandy beaches probably occur

bays.

more frequently

ashore with

than

long-finned pilot whales

any other type of whale.

Pilot

whales

pilot

shorelines than

often than other types.

Mass strandings

may be

a result of the whales'

tight-knit society,

which

whales are

some

particularly

All

and

called gaffs

the animals are

killed,

including

one whale

needs help, the others may follow, and

means they stay together

whales are spotted

despite the risks.

converge shore.

Men

Iceland.

but

hunt

When

some

years the

peaking at 4,325

kill

the

off the coast, the islanders

pilot

whales

much

year,

larger,

1941

so far been Ignored. The islanders justify the

and the meat

the

and

about 1,200 per

by saying that is

a long-standing tradition,

much-needed source

protein. Recently, scientists

years,

International pleas to stop the killing have

all

Faroe Islands, a Danish territory situated

between Scotland and

have died. The average

cull

Every year hundreds of long-finned pilot killed in a traditional

hundreds of

then over 250,000 long-finned

and

stuck as the tide goes out.

whales are

for

continuous records date back to 1709. Since

will stick

into dangerously shallow waters

become

prone

their tight social

which the group

together whatever the hazard.

swims

around Cape Cod.

mass strandings because of

structure, within

into difficulties

hooks

steel

been staged

Long-finned

The species seems to get

slaughtered.

whales are dragged

become more confused around

Strandings are especially frequent

pilot

there, the

pregnant females and calves. The hunt has

coastal areas, for example,

whales on a beach.

Once

normally prefer the open sea, so they probably

whales that are familiar with coastal waters.

ÂŠ Stranded long-finned

LONG-FINNED PILOT WHALE

have shown

that

long-finned pilot whales are very heavily

contaminated with toxic heavy metals such as mercury and other pollutants. Children born to

mothers brain

who

eat lots of whale

damage and may reduce

meat may

suffer

SEE ALSO

may

tail

Dolphin, Bottlenose 3:72; Dolphin, Spinner 3:76

also be another black stripe

area into the side of the

belly.

WHALES AND DOLPHINS COMMON

Common animals that

Group it

DOLPHIN

dolphins are highly sociable

travel, feed,

and sleep

groups.

depends on the season and whether

size

day or night.

500 animals are

most areas groups of 10 to

usual, but occasionally

particularly in the eastern tropical Pacific

groups can be over 2,000-strong. They have

been known to hunt cooperatively, working as a group to herd fish into a tightly packed shoal

where they

When

are easy to grab by the mouthful.

the dolphins are frightened, the group

bunches

tightly

together for defense.

Acrobatic Displays The dolphins are very acrobatic. They can often be seen jumping into the lobtailing,

ride

and

on the

air,

somersaulting,

flipper-slapping.

bow waves

They frequently

of boats or even larger

whales. They are fast swimmers, reaching

speeds of up to 27 miles per hour (43 km/h).

Groups of fast-moving dolphins tend to arch out of the water to breathe at the same time, a

known

behavior

as "porpoising."

They often

cannot be seen for the mass of foam they create.

ÂŠ

Common

dolphins are highly

and

sociable animals that travel, feed,

sleep in groups. In the Pacific groups can

number up

Common

short dives of about 10 seconds to

minutes, with a

maximum

They are one of the whales, using

to 2,000 animals.

dolphins usually only take

two

of eight minutes.

noisiest of the small

clicks for

echolocation and

squeals and high-pitched whistles for

The wide

variations

'populations of

between

common

biologists to try to divide

species.

them

now thought

probably two species of

different

dolphin have led

some

common

that there are

common

dolphin

dolphin; the

(D, capensis).

long-beaked dolphins have a

slightly

The

longer

snout and more muted colors than the short-

beaked

types, with less contrast

between the

black and yellow-white markings.

they have a

beak

flatter

addition,

forehead that meets the

at a shallower angle

than

short-beaked

dolphins. The two species can

also be told apart

biochemically by differences

their

(genetic molecular structure).

on boats nearby can hear them.

into distinct

short-beaked {Delphinus delphis) and the long-

beaked

communication. They are so loud that people

DNA

Fishing Net Deaths

Common illegally

dolphins are sometimes caught

by fishermen

Japan, South America,

and the Azores. They are

also

one of the most

frequent species caught accidentally nets. Large nets that

trapped year.

many

fishing

were used to catch tuna

dolphins, killing thousands every

The animals could not surface to breathe

and consequently drowned. Methods of making the nets more conspicuous to dolphins and built-in

have

escape routes for the trapped animals,

now been

introduced. Such measures

should help reduce the death

toll.

SEA

MAMMALS

Pacific

White-Sided Lagenorhynchus obliquidens

Pacific white-sided dolphins are boldly

and very

to identify,

acrobatic,

Common name

Pacific

making them favorites with

Delphinidae

Order

Cetacea

lively

tourists

and

white-sided dolphin

name Lagenorhynchus

Family

They are also

sociable.

whale-watching boat Scientific

marked, easy

trips.

obliquidens

The Pacific white-sided dolphin looks similar to several other dolphins that have a short snout

.7-2.4 m)

5. 6-7. 8 ft (1

Size Length:

or "beak" projecting

Weight 187-330

beyond

rounded

their

(85-150 kg)

forehead. They might be confused with

Key features Stocky dolphin with

a short, almost

common

snout ("beak") and rounded,

invisible

backward-curving dorsal

black or dark-

fin;

gray back; thin gray stripe running along

both sides from head and curving

toward

tail,

where

opens to a wide flank

on each

patch; gray patch fins

down

above

side

flippers;

dark at front fading to paler at rear; belly

dolphins, which also have pale side

patches and share the same areas of ocean.

common

However,

much

dolphins have a

longer beak compared with the rounded face

and

short, almost nonexistent

Pacific

beak of the

white-sided dolphin.

white

Habits

Highly sociable dolphin, usually seen

large

Variable Markings

groups occasionally numbering thousands; lively

and acrobatic; curious, often coming

close to inspect boats

Breeding

Single calf born every 2-3 years

afte’'

gestation period of about 10-12 months.

Weaned years,

years

18 months; sexually mature at 10

sometimes more. May in captivity,

The markings on white-sided dolphins can vary

live

position

Clicks

color.

The back

black or dark

gray with a thin, pale-gray stripe running along

both sides from the head, leading to a wide, pale patch near the

tail.

There

also a pale-

up to 20 gray patch on each side above the flippers. The

the wild

fins are

Voice

and

dark at the front, fading to paler at the

and whistles

The dorsal

rear.

Diet

Squid and small shoaling

Habitat

Mainly offshore waters; occasionally seen

curving.

inshore

water

fin

rounded and backward-

fish

keep

When

they swim slowly, the dolphins

their bodies just

below the surface with

deep the dorsal

fin

pointing out of the water, making

Distribution Cool-temperate waters of the North Pacific

them appear Status

Population:

million;

throughout most of

CITES

its

II.

Common

rather like sharks.

The species name obliquidens means

range "slanting teeth," from the

backward toward the

way they

throat.

are angled

These backward-

pointing teeth help dolphins hold and swallow their slippery prey of squid Pacific

and small

white-sided dolphins only

cool-temperate waters of the North

where streams

of cold water flow

coastlines

sometimes come

—where there

live in

the

Pacific,

down from

the Arctic. They spend most of their offshore, but

fish.

lives

closer to

deeper water

—

feed at certain times of the year. They can be

SEE ALSO

Dolphin,

Common

3:68; Dolphin, Bottlenose 3:72; Dolphin, Spinner 3:76

WHALES AND DOLPHINS

seen from

Columbia (Vancouver

British

Island)

and southeastern Alaska southward to southern California

and Mexico.

Pacific

ÂŠ

Pacific

curious.

They

will

swim near boats inspect their

them or

bow

and

make them

some

firm favorite with

wake and

They are also

of boats.

will

often

Because of

come

their habits they are

They swim

whale-watching

common

waters of southern California.

close to

Pacific

popular with the coastal

trips, especially in

white-sided dolphins are hunted

small boats using hand-held harpoons.

Tourists' Favorites

watching tours off the

The dolphins are

California coast.

to love

showing

lively

off.

over 2,700 animals were

and

They

acrobatic,

will

and seem

sometimes breach

(leap high out of the

water) and perform a full

Japan for their meat. They are caught from

of the large baleen whales.

whale-

ride in

of the water (spy-hopping) to get a better look. in

and occasionally

dolphins, Risso's dolphins,

wave. Their

lively antics

to 2,000 animals.

with other cetaceans too, including

ride in

bow wave

and often

fast

boats to inspect them, poking their heads out

groups, often 100-strong, and sometimes

huge herds of up

often

the

They can swim

intensely curious

white-sided dolphins are highly

sociable animals. They are always seen

white-sided

dolphins are sociable

for fun.

PACIFIC WHITE-SIDED DOLPHIN

midair somersault

before landing with a splash, apparently just

are

killed;

no accurate population

known

1984

but since there

figures,

hunting on such a scale

not

threatening

survival of the species in that part of the world. Pacific

many

white-sided dolphins are

among

dolphins that accidentally drown

They are also caught

fishing nets.

for use

dolphinaria because of their acrobatic

and

friendly nature.

the

skills

the 30 years

to 1985 over 300 animals were

taken into

captivity,

third survived

but only a

more than

a year.

The "Lags" The

Pacific

group of

of a

known

white-sided dolphin

as "Lags," from their generic

of Lagenorhynchus. They have similar

shapes and

one

closely related dolphins

sizes, a short

name

body

beak, and are

sociable and acrobatic. They can be told

apart by differences their distribution,

teeth.

their markings,

and the number of

The other Lags are the white-

beaked dolphin

{L.

albirostris),

Atlantic white-sided dolphin (I.

acutus), dusky dolphin

(L obscurus),

dolphin

(/..

and hourglass crudger).

further related species,

Lagenodelphis hosei or Fraser's dolphin,

has a

short, stubby beak, is

thought to be a

and link

between the Lags and the

common

dolphin.

SEA

MAMMALS

Bottlenose

Dolphin

Tursiops truncatus

Bottlenose dolphins are highly sociai, inteiiigent Common name

Bottlenose

animais. They form ciose, cooperative friendships"

dolphin Scientific

name

Family

Delphinidae

Order

Cetacea

out

Length: 7.5-12.5

Size

with each other, and

Tursiops truncatus

(2. 3-3. 8

human

some

individuais wiii even seeic,

contact.

Bohlenose dolphins are the most familiar species

of small cetaceans,

made famous

by the

Weight 330-1,433

televison series Flipper.

(150-650 kg)

Key features Robust dolphin with

studied of

fondness for coastal waters makes them easy to

wide head and body and rounded forehead; body mostly gray with a

They are the best

whales, partly because their

all

lighter or

observe, and also because they adapt to

white

They are the

captivity better than other species.

underside; color patterns are variable

dolphins most frequently seen along the shores Habits

Active, social dolphin usually seen in groups

Breeding

Single calf born every

4-5 years

gestation period of

year.

of the United States.

years; females sexually

males at 10-12 years. in

Voice Diet

the wild, fewer

Weaned

mature

May

after

4-5

at 5-1 2 years,

live

up to 50 years

in captivity

High-pitched whistles and

Variable |

Bottlenoses are robust dolphins, with a short,

wide snout

clicks

Large variety of food, including

Body Shape

(or "beak"). Their size

vary widely depending fish,

the dolphins

squid,

live,

on where

and pattern

the world

and whether they come from

octopus, cuttlefish, and mollusks

Habitat

Wide range

of habitats from

open water to

harbors, bays, lagoons, estuaries,

coastal or offshore waters.

the northwestern

Atlantic coastal dolphins tend to be smaller

and rocky

and

slimmer than their offshore counterparts. Body

reefs

size also

Distribution Widespread

temperate and tropical

depends on the temperature

water: Dolphins

waters

blubber to Status

Population:

unknown, perhaps hundreds

thousands; CITES

II.

A common

of the

}

colder seas need

living in

keep warm. Because

five of their

of I

species,

especially in particular areas

seven neck bones are not fused as

their

rigidly

together

other whales, they have more mobility

necks than most other cetaceans and thus

can nod and turn their heads. Bottlenose dolphins

temperate and

live in

tropical seas.

wide range of

Along the western

Atlantic coast they can be seen from to the Caribbean

side of the United States they are

the coast from

New

Panama

found along

to southern California.

Since color, markings, and healed scars

each individual

Jersey

and Panama. On the other

different,

make

has been possible to

keep a photographic catalog of the animals. Studies

show

that the dolphins living near the

coast return to the

SEE ALSO Whale,

now

Protection Act of 1972.

strong social

bottlenose dolphins cooperate with fishermen.

one area and

a bottlenose dolphin that has lived

some

has also

Killer/Orca 3:62

special "friends."

â&#x20AC;&#x201D;

Stenella longirostris]

Spinner dolphins are famous for their stunning aerial displays.

Common name Scientific

name

accompany ships for long periods

Stenella longirostris

Delphinidae

Order

Cetacea

Size

Length: 5.5-8

The spinner dolphin ft

(1.7-2. 4 m); Southeast Asian

animals are smaller: about 4.5 (1.4

100-165

Few

dolphin:

many

As they

as often.

others

at sea.

champion leaping

the will

jump

nearly as high or

clear the water, the dolphins

m) long spin

Weight

will spin

times before landing with a great splash. They often

Spinner dolphin

Family

They perform huge leaps and

(45-75

kg);

animals: adults about

Southeast Asian

and

No other

twist.

wild dolphins

this,

apart from the closely related clymene or short-

(22 kg)

snouted spinner dolphins. Spinner dolphins can Key features Slender body;

long, thin snout ("beak");

3-toned coloring: dark on top fading to with a

Habits

Active,

leap

fast-swimming dolphin; often swims

characteristic leaps, spinning in

into the air

to seven times before landing with a

light belly

with boats for long periods of time; performs

swims

up to 10 feet

up to 7 times;

splash

why of

back or

their

they leap

sides.

such a way.

may be

communication within the group

gestation period of 10.5 months.

Weaned

(the

way

males at 7-10 years.

May

live

sound

may be

of dislodging skin parasites. Otherwise,

may be

just for fun.

up to

about 50 years

Long Snouts

and whistles

Voice

Clicks

Diet

Fish

Habitat

Mainly open ocean, but sometimes inshore

The spinner dolphin

one of

group of

oceanic dolphins that have a long, narrow

and squid

Distribution Tropical and subtropical seas throughout

snout. The genus

name

Stenella

comes from the

Greek word stenos, meaning "narrow," and the

name,

means "long snout."

world

species

Population: several million;

The other names given to the spinner dolphin

lUCN Lower

conservation dependent; CITES in

1-2 years; females sexually mature at 4-7

Status

form

groups of usually about 30 animals

Single calf born about every 3 years after

years,

huge

No one knows

of the splash travels a long way), or

Breeding

and spin up

gray,

II.

Risk:

Populations

longirostris,

rollover dolphin

and long-beaked dolphin

the eastern Pacific are severely reduced

also descriptive.

from deaths associated with tuna

â&#x20AC;&#x201D;are

not leaping, a spinner

fisheries

dolphin can be recognized by

its

long, slender

body and well-defined, three-tone shape of the dorsal

fin varies

coloring.

and with the sex of the animal. Sometimes erect or even forward-pointing, so that

The

between regions

looks

has been put on back to front. Spinner

dolphins have between 172 and 252 teeth,

more than any other cetacean

species.

Spinners are sociable dolphins, usually seen in

groups of between

five

and 30 animals,

although groups of 1,000 can occur

the open

ocean. Even larger groups have been reported

SEE ALSO

Dolphin,

Common

3:68; Dolphin, Bottlenose 3:72

and

its

habitat, small size,

small, blunt-tipped dorsal fin.

dark gray on the back, fading

dolphins and

many

of the larger whales. Usually

they just swim slowly, surfacing with a slow

down

the flanks to white on the

porpoises have a black chin and

ÂŠ

Harbor porpoises are

They do not

traits

show some exhibitionist

common

of the dolphins

many

distinctive

pop

when

â&#x20AC;&#x201D;

Decreasing Numbers

sudden outburst that sounds

five,

some

but never form large

of the dolphins.

live

Groups

schools

breaching, bodysurfing,

sometimes come together to feed when there

and

a large shoal of fish or other

It is

actually fairly rare to see

prey,

no evidence

However, there

above the water.

social structures that exist in

species.

suggesting

some dolphins

do, with

all

formation

are often very heavily polluted,

and many of

taken over for industry or shipping. Boat is

traffic

another hazard for such shy creatures, and

numbers

dying from disease.

for the strong

owing to

The coastal waters where they

there have also been cases of large

some dolphin

They also do not swim

activities.

rapidly

their habitats are lost as natural coastlines are

they can communicate over long distances.

much of the porpoise

numbers have decreased

human

small

larger whales, such as

flipper-slapping.

Harbor porpoises were once very common, but

their

Harbor porpoises usually swim

they breathe.

also

or sneeze.

groups of two to

and

that curves up slightly so they look as

they are smiling. Their breathing

rather shy creatures.

of the

mouth

lips

roll

every 10 to 20 seconds, making a "pop" sound

Harbor

belly.

Harbor porpoises are like

animals coming up

still

hunted

some

parts of the world, with the largest catches

around

Iceland.

Many thousands

also

drown

fishing nets

â&#x20AC;&#x201D;

groups tend to appear as more of a

vertically in

the water anchored to the seafloor.

disorganized "rabble," with individuals crossing

They are used to catch low-swimming

each other's paths and making sudden spurts

as cod

for air at the

same

time. Harbor porpoise

and charges. They are not the

most

exciting

cetaceans to watch because they are timid and

tend to

show

very

little

waves

to find

caught

of ships or perform any of the other

fish

and flounder; but since porpoises

become trapped. The

bow

interesting behaviors so characteristic of

which hang

such

also

tend to feed near the seafloor, they often

of themselves above

water. They never leap high or ride the

particularly in gillnets,

fishing industry

ways to reduce the number in gillnets.

One method

devices called "pingers" that noises to

warn the animals

trying

of dolphins

to attach

make underwater

to keep away.

SEA

MAMMALS

Beluga The beluga

Common name Scientific

name

alter the

shape of its forehead and

appearing

Order

Cetacea

Size

Length: 10-16

to smile,

lips,

frown, or whistle.

For most of the year adult belugas are pure ft

(3-5 m). Male larger than

female

white, only becoming tinged with yellow

period

summer

the

for.

before the seasonal molt.

common name

Their coloration explains their

when

white whale. Calves are dark gray

first

born, but the color fades during their immature

Weight

1,100-3,300

(500-1,500 kg) years until they reach about four years old,

Key features

head small and rounded;

fin;

when

flippers broad,

paddle shaped, and highly mobile;

short,

Habits

no dorsal

Stocky, white-colored whale;

tail

color

become

they

due to

white. The lightening

a reduction

(called

Social animals, rarely seen alone; masculine

shed the surface layers of their

nursery groups of mature

melanin)

the skin.

the dark pigment

fluke frequently asymmetrical

groups of 3-1

summer belugas old, slightly

yellow skin to reveal the new, gleaming-white

females and several young of various ages; during migrations congregations of hundreds or even thousands

Breeding

One

calf

may be seen

Weaned

20-24

months; females sexually mature at 5 years, males

8 years.

May

live

30-40 years

some have been known

wild,

years;

Voice

moos,

Trills,

sometimes

clicks,

live

to 50

captivity

Coastal and offshore

near

ice;

head

possible, they

instead. Estuaries

of fresh water,

that

not

for melting glacier fronts

and

both sources

glaciers are

which may quicken the shedding

The belugas

process.

also rub themselves

on the

seabed to help themselves molt.

squeaks, and twitters;

Layers of Fat fish,

crustaceans, worms, and mollusks

Habitat

estuaries; but

the

called "sea canary"

Mostly bottom feeders, eating

Diet

does not survive so long

skin underneath. At that time the animals like

to congregate

born every 3 years after gestation

period of 14-14.5 months.

cold waters, usually

shallow waters,

rivers,

The beluga

and rotund whale

quite a small

with short, wide flippers that curl up at the

There

no dorsal

and estuaries scientific

Distribution Coasts of arctic regions of North America,

name

fin

â&#x20AC;&#x201D;accounting

for

tips.

its

Delphinapterus, meaning

"dolphin without a wing." However, there

Greenland, northern Russia, and Svalbard short, raised ridge

Status

Population: about 100,000;

CITES

lUCN Vulnerable;

where the

fin

would normally

be found. The beluga has a very thick

layers of

blubber to keep arctic seas.

well insulated

the cold

so fat that the head looks too

small for the body. Unlike

most other whales,

belugas have a very mobile neck that allows

them

nod and turn

inquisitive

their head.

They are

animals and use their neck to look

around when they

lift

their

heads out of the

water. Another feature of the beluga ability to

break through solid

inches (10 cm) thick by

SEE ALSO

Bear, Polar 2:84;

Narwhal 3:84

to its

produce several facial expressions.

Delphinapterus leucas

Monodontidae

among whales owing

unique

ability to

Beluga (white whale)

Family

Delphinapterus leucas

ice

ramming

its

up to four it

from

often

can

ÂŠ

The belugas' deathly

white skin and

swimming

undulating

motion makes them look like

underwater ghosts.

For a period in the

underneath, using the firm melonlike structure

on in

its

head. The impact creates breathing holes

packed

ice.

However, belugas cannot stay

waters that are covered by very thick

ice,

they would not be able to break through

breathe the

air

since it

seconds, but studies have

summer belugas become

that belugas

routinely dive for periods of nine to 13 minutes.

beluga that

was seen Surface

swam up

to be

ice

the Rhine River

submerged

for

1966

70 minutes.

not a great problem to belugas,

since they can travel

they need.

shown

up to

to 2 miles

km) underwater. But they can become

tinged with yellow

Ghosts of the Deep

trapped

before the seasonal

Belugas are normally slow swimmers. They

prey for hunters and polar bears. Belugas often

molt occurs.

usually travel at

about

to 5 miles per hour

(1.5 to 8 km/h), but can reach

miles per hour (23 km/h)

very supple

speeds of 14

pursued. They are

and can operate

their

so that

tail

the sea

most of the year belugas remain

offshore, near sea

shore

which makes them easy

from polar bear attacks.

carry scars

For

ice,

ice.

summer, since

They move closer to rivers are

not frozen and

they can swim backward, allowing them to

can be entered to find food. After mating they

maneuver

very shallow water that just covers

move

They move with

migrate back to colder areas

their bodies.

undulating motion that can like

ghostly apparitions

a gently

make them

look

murky waters. They

surface to breathe about every 30 to

warmer waters

are strong

enough

to give birth

when

to cope. Migrations appear

to be affected by the distribution

abundance

of prey

and then

the calves

and

and the extent of pack

ice.

Belugas are

among

the most social of

Some others

whales. Males and

populations migrate long distances, while live IS

permanently

very rare to see a solitary beluga, since

females usually form

they are highly social animals. The strongest

separate groups that

social

bond

between

mother and her

calf:

migrations the different groups join together

herds that can contain hundreds or even

She cares

migrations in huge herds

Although the breeding cycle

containing hundreds or

years long, mothers sometimes suckle their

family groups.

even thousands of

young

ahead of migrating groups, appearing to

animals. However, the

time between births to three years. Groups

for her

for

young over

normally two

up to 24 months, and extend the

smaller family units

consisting of a mature female, her

remain distinguishable.

calf,

and

several of her

newborn

are also separate groups of will

Kilier/Orca 3:62,

possible to

make out

Some

the

many

smaller

adults have been seen

follow. Larger aggregations also

where food

places

one of the most vocal of the

toothed whales and "sea canary."

form

abundant.

The beluga

merge with

female groups during the breeding season.

is still

explore passages through pack ice for others to

most recent young are

about three to 15 males that

SEE ALSO Whale,

can extend over 6 miles (10 km) or more, but

several years. is

thousands of belugas. These migrating groups

join together during

common. There

Russian offshore waters the male groups

sometimes contain up to 500 animals. During

quite small areas.

sometimes known as the

has a fantastic repertoire of

Whale, Humpback 3:102

WHALES AND DOLPHINS BELUGA

What

squeaks, moos, and twitters.

trills,

amazing about the noise produced by belugas is

that

The

can easily be heard above water as

Talkative Beluga

well as below. Underwater the sound of a herd

of belugas

apparently comparable to a noisy

barnyard. The sounds are used to

communicate

with other whales. The beluga also has a wide

which are thought

facial expressions,

range of

produce

when

sonar

(called

takes place underwater),

bouncing echoes off prey and the seabed to help the animals find their

way around. The

waters where belugas

are often covered

with

and there

ice,

months

live

sometimes no sunlight

at a time. Visibility

quite poor,

and sonar

way

then a useful

smile, frown, or

slaps

threat. Physical contact

animals

even whistle. Lobtailing,

its tail

â&#x20AC;&#x201D;they

will also

One

killer

of the predators of the beluga

whale

(orca).

A salmon

fishery

understood. There

some evidence

suggests the beluga uses

system of

its

sonar

packed

find breathing holes in

most

that they have the

not

the

in Bristol

whale noises

bears attack belugas that

that

small areas of

thought

effective echolocation

They

also attack

when

come

to breathe

open water surrounded by

ice.

whales that become stranded

the tide has gone out: Belugas can

survive until the next tide

cetaceans.

all

prey to polar

bears and sometimes even to walruses. Polar

fully

abilities

ice.

become

away. Belugas can also

apparently used to help with is

thought to be a

'-to*/*:?-

underwater to keep salmon-stealing belugas

how

clap their jaws

love to rub against each other.

bulging forehead (often called the melon) of a is

the is

very important to these very social

Bay, Alaska, played recorded killer

beluga

when

on the surface of the water,

avoiding obstacles and hunting for prey. The

echolocation, but exactly

alter their lips

for

therefore often

and seem to

together to create a drumming sound, which

used for echolocation

an impressive vocal

They often appear quite comical when they

repertoire.

another form of communication. They

toothed whales, belugas

clicks that are

variety of facial expressions as well as having

whale rhythmically

to be another form of communication. Like other

elugas are very communicative animals that can produce a

they have been

stranded, but they are vulnerable to polar bears

Diverse Diet The beluga's

and people

diet

and includes worms,

diverse

crustaceans, mollusks, and is

found on the seabed

1,500 feet (500 m).

fish.

Most of

scan the ocean floor for food. Having detected prey by sight or sonar, to

draw the

squirts

victim into

water

among

from

its lips

its

produce suction

mouth. Otherwise

stones. Belugas have about 32 to

40 peglike teeth, which are not fully until

the whale

teeth often

two

much

for feeding

their prey

or three years old.

become worn and

able to grasp prey.

grown

In fact,

The

would not be

they are not used

because belugas swallow

whole. The teeth

may wear out

producing sound: The animals clap their jaws together, are

making loud drumming

thought to be used as a

sounds that

threat.

Humans

are the

main threat to belugas. Belugas use the same migration routes every year, which allows

population of belugas

them

The world

ÂŠ Belugas produce loud drumming sounds by

thought to number

clapping their jaws

about 100,000, but some populations are

together

almost extinct because of overexploitation.

mouth

Belugas

them

at small animals, dislodging

such a situation.

to be exploited by hunters.

mobile neck allows

Its

food

its

depths of up to

waters,

move

seasonally to coastal shallow

where they are

at risk

Another threat to belugas

from pollution.

that their coastal

habitats are being spoiled by exploration for

oil

and the building of hydroelectric dams. Both activities

(1);

(2) is

the pursed

believed to

be used when the animals are feeding from the seabed. The

lips

produce suction to draw prey into the mouth.

often require detonation of explosives

underwater, which has an adverse effect on the health of belugas. Ironically, the beluga will

probably be saved from overhunting because industrial pollution has raised

their

meat

to such high

longer sold for

mercury

levels that

levels in

they are no

human consumption. 83

SEA

MAMMALS

Narwhal Once thought

Monodon monoceros

be the horn of the legendary unicorn,

the long, spiraled tusk of the narwhal

Common name

and fascinating cetacean.

distinctive

Narwhal Scientific

name Monodon monoceros

word

The name narwhal derives from the Norse Family

Monodontidae

Order

Cetacea

Size

Length: 13-16

meaning "corpse whale." due to the animal's habit ft

(4-5 m). Male larger

and

than female

Weight

(800-1,600 kg)

swimming

makes

Narwhals are

rotting corpse.

Key features

look

adaptation to

life in

Its

like a

shape to

similar in

the beluga; both species lack a dorsal

Stocky toothed

belly

motionless for several minutes.

lying

peculiar mottled skin also

1,760-3,520

could have arisen

fin

as an

the cold arctic seas.

whale with no dorsal fin

and short

dorsal fin increases the surface area of the

with

flippers; skin colored

patches of gray-green, cream, and black;

males have unique long, Habits

Social: usually

seen

spiral

whale and would thus speed the

tusk loss.

groups of up to 20

could also

insulation over the rest of the

together as part of a

much

warm

narwhals

larger herd

the

ice-

layers of blubber provide

packed waters. Thick

animals; sometimes separate groups

according to age and sex; often moves

rate of heat

become damaged

icy

body to keep

cold waters.

containing thousands of individuals

Breeding

One

calf

months; sexually mature live

Unicornlike Horn

born every 3 years after gestation

Weaned

period of 14-15 months.

6-8

years.

The narwhal

renowned

for having a long,

May From medieval times seamen and

spiraled tusk.

30-40 years

traders distributed the spectacular tusks around

Voice

Clicks, squeals,

and whistles used

for

Europe. People believed they were unicorn tusks

communication or navigation

with magical powers that could detect Diet

Mostly

Habitat

Cold

fish,

squid,

enemies had poisoned arctic seas, generally

summer sometimes seen fjords,

near sea

estuaries,

narwhal tusk

deep

and bays; migrates when habitat

mideastern Canada

II.

One

upper

lip.

males.

grow

Population: about 25,000-30,000; of the less

their food. Actually, the

an extremely long incisor tooth

that protrudes from the left-hand side of the

Distribution Coastal; mainly western Greenland to

Deficient; CITES

their

ice; in

unfavorable

Status

and shrimp

lUCN Data

The tusks are generally found only small

number

of males

second tusk on the right-hand

Occasionally females

grow

sometimes side.

a single thin tusk

abundant too.

whales, status uncertain

The

the tusk

spiral will

pattern

grow

interference with

believed to ensure that

straight, preventing

swimming.

Sometimes the tusks can reach astonishing lengths.

pounds

10-foot (3-m) tusk weighing 20

(9 kg)

5-foot (4.5-m) whale

not

unknown. There have been many ingenious ideas to explain the purpose of this

extraordinary structure.

weapon

Some

believe

even boats. Others suggest that

SEE ALSO

Bear, Polar 2:84;

to be a

with which to attack other narwhals or it

Whale, Killer/Orca 3:62; Beluga 3:80; Deer and Relatives

used to 6:10

makes

this

WHALES AND DOLPHINS NARWHAL

ÂŠ Narwhals are a sociable species. They form

migrating herds of hundreds or even

thousands of animals made up of smaller groups of

whales of similar size or sexual

make

â&#x20AC;&#x2DC;

unlikely to be a

are social animals

aggressive. ideas:

breathing holes

or to spear food.

in ice

weapon,

since narwhals

can also

rule

out the other two

would

creating breathing holes, then females

have them too. the tusk

used

hierarchies, like antlers

The narwhal

extremely

when

herds that migrate unsuitable in

generally thought that

jousts with other males to establish

dominance

over

now

an ornament carried by males and

â&#x20AC;&#x201D;

the

for example,

fall.

When

when

becomes

the seas freeze

migrating, hundreds or

even thousands of narwhals may

travel

together. However, these large aggregations actually consist of

many

smaller groups

hunted narwhals for centuries. The as "muktuk," it

valued because

good source

tourists

and

collectors.

still

skin,

when

of vitamins.

known

eaten

The unique

oil

for heating

4 to 6 inches

fed to sled

and

lighting.

layer of blubber

0 to 15 cm) thick

will yield at

least

100 gallons (455

Inuit

hunted narwhals from kayaks using

toll.

The

The meat

dogs, and the blubber can be used to produce

oil.

Traditionally,

some modern hunters have

motorboats and

such large numbers

inevitably attracts the attention of hunters.

released into the sea. However, they are

threatened by hunting. Native people have

harpoons, but

containing whales of a similar size or sexual status. Migrating in

from pollutants

tusks are prized, since they can be sold to

forming

their habitat

Narwhals mostly avoid waters close inshore, so are less at risk

raw,

deer.

social,

killer

and Greenland sharks; but the

(orcas),

main threat comes from humans.

and do not tend to be

the tusk were needed for feeding and

predators of narwhals include polar bears,

whales

status.

rifles,

the

fast

which increase the death

Populations must be monitored carefully to

ensure the narwhals are not overharvested.

SEA

MAMMALS

Sperm Whale Common name

Sperm

whale Scientific

name

Physeter catodon

For

many years

image of the

the

Physeter

catodon

great sperm whale portrayed by

Family

Physeteridae

whalers filled people with terror

Order

Cetacea

Bat a greater knowledge of these

Length: male 49-62

Size

amazing creatures means they are

(15-19 m); female 26-39

Weight

(8-12 m)

now viewed

with admiration.

Male 51 tons (45 tonnes), maximum 65 tons (57 tonnes); female 17 tons (15 tonnes),

maximum 27

tons (24 tonnes)

It is

relatively easy

since

Key features

Largest

identify

the sperm whale,

the largest of the toothed whales and

has a distinctive, flat-ended head. The head

toothed whale; dark-gray

to dark-brown skin with white patches belly; skin

has a wrinkled appearance; often

scarred; large, square-ended head; dorsal fin

reduced to a small, triangular hump; short,

actually contains the largest brain in the animal

kingdom, although

makes up about 0.02

only

percent of the animal's total body weight. The

unusual shape of the head includes a forehead

paddle-shaped flippers

that forms a boxlike cavity large

Habits

Females and young

young males 20-25

bachelor schools, both with

males

individuals; older

solitary or in

small groups; join breeding schools to

Breeding

Single calf born every

4-6 years

for a

car to

fit

inside.

The

cavity actually contains a

huge mass of spermaceti, an

was once

highly prized for lubricating fine

machinery such as clocks.

Weaned

oily material that

the spermaceti organ

what use

unclear

whale

to the

itself.

1-3 years, sometimes longer; females

sexually

mature

18-21 years.

Voice

mate

after

gestation period of 14-16 months. at

enough

breeding schools,

live in

Clicks used for

7-13

May

live

years,

at least

Some

males at

60-70 years

believe

may

control

buoyancy when

diving for food; others suggest that

may

help

with the animal's echolocation system.

communication and

echolocation

Mostly squid; also

Diet

Habitat

cuttle,

octopus, and

fish

Deep waters, often near the continental females and calves stay

warm

shelf;

waters,

males migrate to colder feeding grounds Distribution Found

Status

in all

the oceans of the world

Population: estimates vary from 200,000

(minimum) to

1.5 million

Vulnerable; CITES

(maximum); lUCN

Wrinkled Skin Sperm whales have very

are also unique because they

distinctive skin that

prune. The wrinkling too

wrinkled

like a

may have an

important function, perhaps to reduce turbulence along the animal's body, assisting

passage through the water. The

friction-free

flippers are relatively short,

and the

reduced to a rounded hump.

hump

runs from the

powerful at

tail

to the

tail

dorsal fin

series of

flukes.

bumps

The

allows the sperm whale to travel

speeds up to 23 miles per hour (37 km/h).

Only the lower jaw has true teeth, with about

20 to 26

pairs.

pegs, and can

(20 cm) long. present

SEE ALSO Whale,

Killer/Orca 3:62

WHALES AND DOLPHINS SPERM WHALE

member

injured, they will encircle

and use

their

powerful

means of defense.

protective

of their group

it,

tails

facing inward as a

the past such

behavior proved disastrous for the whales, which could be picked off one

by one by whalers.

spermaceti

oil,

one of the most valuable of

whale products. Ambergris, in

their intestines,

perfume

industry.

the whalers (1

—

found

a substance

was formerly used

the

was extremely valuable

a piece

weighing 250 pounds

was worth more than the wages

3 kg)

all

for

the entire crew for a whole year. Today

Sperm whales

synthetic substances are used. are

now

protected by International agreement.

Literary Character In

the novel

Moby

Dick by

Herman

sperm whale was portrayed as

Melville the

monster of the

Hunting sperm whales was once very

sea.

dangerous and was looked on as an act of great bravery. The whalers

would row

open boat to spear the whales with hand-held harpoons. The whale would sometimes turn on the whalers

in self

defense.

could knock them

out of their small boat, a fraction of size,

and crush them

in its

whalers feared the mighty to defend themselves and

their

powerful

their

weakened comrade.

tails

put themselves at

companion that As the

risk

Individuals will even

to try to rescue a

danger.

largest of the

toothed whales, the

sperm whale was a valuable catch to any whaler, not only for

its

plentiful supply of

raised high

Whaling was once a

dangerous risks

activity.

The

faced by whalers

were described novel

Moby

Dick.

the

made

its

own

powerful jaws. The tail

that

would be

above the water before the whale

deep

dive, calling

"the hand of God."

However, the advancement of whaling technology, notably diesel-driven boats

more powerful steam- and

and the exploding harpoon

gun, denied the sperm whales any chance of

defending themselves. They were slaughtered

many

years before being protected by

blubber, but also the provision of spermaceti

for

and ambergris. Whalers once believed

international law. Because whalers selectively

that the material

was

the forehead

the sperm produced by

male mammals.

from that

mistaken belief that the sperm

whale and

single

its oil

take their name.

sperm whale could provide

whalers with

5 barrels of

hunted the larger males, they created an

uneven

ratio of

males to females. The

combination of the naturally slow population

growth and the

selective hunting of the larger

males has resulted

low calving

rates.

That has

slowed the recovery of the sperm whale population, despite worldwide protection.

SEA

MAMMALS

Northern Bottlenose

Whale Common name Scientific

Northern bottlenose whale

name Hyperoodon

One of the

ampullatus

longest and deepest divers of all whales

Family

Ziphiidae

and dolphins,

Order

Cetacea

recorded diving 23-30

Length:

Size

Hyperoodon ampullatus

the northern bottlenose whale has been to

depths of 4,500 feet (1,370 m).

(7-9 m). Male larger than

female

The northern bottlenose whale

beaked whales.

and Weight

Male 8 tons

(7.5 tonnes):

of the

a narrow, pointed

snout

"beak") quite

(or

female 6.6 tons similar to that of the bottlenose dolphin.

(5.8 tonnes)

distinctive,

Key features Medium-sized whale with

bulging forehead

Its

more prominent

distinctive,

may overhang

older males and

the beak.

bulbous forehead and narrow snout ("beak");

lower jaw of beak extends

the bulbous forehead can be seen, the whales

slightly further

than upper; 2 main teeth at in

of lower

tip

jaw are easy to identify, since they are the only

males; dorsal (back or spinal) regions dark

gray to brown, lighter on flukes

Habits

one

has a long, cylindrical body

no notch

belly;

beaked whales

rounded

(tail fin)

Usually lives

the North Atlantic with such a

head. Adults are dark

gray to brown on their dorsal (back or spinal)

groups of 1-4; larger herds

formed when migrating and

profile to the

the breeding

regions and are a lighter gray or creamy

brown

season; older males often travel alone

on the underside. Older males are Breeding

One

calf

born every 2-3 years after gestation

period of about a year.

Weaned

months; females sexually mature males

years,

about 7-9

years.

about

become

Little

known, but uses

Mainly squid; also

Diet

starfish,

Habitat

fish,

clicks

and whistles

whale has two main

sea cucumbers, cuttle,

have

arctic waters, preferring

mouth in

four,

teeth, but

some males

which are located on the

lower jaw and are not exposed

offshore areas with water depths of over

3,300

Juveniles

in color.

are black to chocolate brown. The bottlenose

and prawns

Cold-temperate and

white, and occasionally their entire

body becomes yellow-white

live

approximately 30-40 years

Voice

recognized, since their forehead and beak

8-12

May

easily

shut. These teeth

tip

when

do not

of the

the

usually erupt

females, but remain below the gums. Both

(1,000 m)

males and females may have rows of tiny teeth Distribution North Atlantic oceans and

arctic regions,

along both jaws.

avoiding shallow waters

Status

Population: probably a

Lower

Risk:

few thousand; lUCN

conservation dependent; CITES

Insufficiently

known; has declined due to

hunting

Deep-Sea Divers II.

The northern bottlenose whale for

its

amazing diving

abilities.

well

known

Whalers have

reported they can be submerged for up to

two

hours, but the typical dive time, without

causing any stress to the animal, minutes.

When

far horizontally

close to

diving, they

do not

14 to 70 travel very

and often surface again very

where the

that air-breathing

dive began.

mammals

amazing

can remain

underwater for such a long time. They are also able to dive to extraordinary depths. Dives

SEE ALSO

Dolphin, Bottlenose 3:72

WHALES AND DOLPHINS NORTHERN

ÂŽ

generally range from

The northern

250 to 2,500

feet (76 to

bottlenose whale

760 m)

regularly dives to depths

4,500 feet (1,372 m) has been recorded.

of 2,500 feet (760 m),

rummage around

seabed for

its

the

main food

depth, but an astounding depth of

The bulk of the

and

sometimes much deeper,

diet

squid

in its

stomach. The whales have to use

deep, sustained dives to find their food, which

and invertebrates, from the

of squid. The whales can

also includes fish

be submerged for up to

seabed. The stomachs of

two hours, but the more

been found to contain

usual dive time

clay, indicating

somewhere between

One whale

squid:

individuals have

of shell, stones,

may

that they

rummage around

some

bits

and

use their snout to

the seabed for food.

distributed

3,000 feet (914 m) deep. preference for deep water

abundance and are found

sea is

at least

thought that

due

cold-temperate and

their

They

arctic regions

and prefer water temperatures that are

between 32 and 62.6Â°F the to

warmer waters

mate and

(0 to 17Â°C).

winter,

give birth,

They use

swimming south

and then migrating

north again for the summer.

approach boats quite

fearlessly,

also

a calf

approaches a

swim between

known

and the

vessel.

mother

They are

to be loyal animals that will stay

with injured companions die.

ship, the

until

they recover or

Unfortunately, such behavior allowed

to be exploited by whalers

them

the past. Since

they are so curious, the whalers could simply

an area and wait for the whales to

reduced

numbers were

the 19th century

hunted for

their

spermaceti

oil

come

drastically

when

they were

blubber and the valuable

found

in their

heads. Northern

bottlenose whales have been protected by the

to the

distribution of their prey.

will

to them. Their

the North Atlantic. They are most

commonly found where the

will

but mothers are extremely protective of their calves.

drift in

Northern bottlenose whales are widely

and 70 minutes.

Loyal Friends Northern bottlenose whales are nosy, inquisitive animals and

was found with more than 1,000 beaks from

BOTTLENOSE WHALE

International

yet there

Whaling Commission since 1977,

insufficient information to

make

population estimate. Although they are no longer

danger from whalers, the

whales are

still

friendly

threatened by humans through

disturbance, pollution, and reduction

owing to human

activities,

food

such as fishing.

SEA

MAMMALS

Eschrichtius robustus

Gray whales make one of the longest migrations of

mammal— an

any

annual round

trip

of up

12,500

miles (20,000 km). Over one animal's lifetime the total Family

Eschrichtiidae

Order

Cetacea

distance covered

Size Length; male 39-46

(12-14 m); female 43-49

moon and

equivalent to

swimming

to the

back.

(13-15 m)

Weight 26-40

tons

The gray whale

one of the most well

known

(22.5-35 tonnes)

and best understood of Key features Robust baleen whale;

upwardly

fairly short,

coastal habitat

its

the cetaceans, owing

all

and

friendly character.

cun/ed head; skin mottled gray, covered with

patches of barnacles and whale dorsal

but low

fin,

bumps running

hump

lice;

Stockier than

followed by series

to the large

tail

most

more slender

rorquals, but

than the bulky right whales, grays exhibit

flukes;

features that are intermediate

between the two.

and paddle shaped

flippers small

However, they are different from other baleen Habits

Generally found larger

small groups of 1-3, but

whales, and as a

groups of up to 16 sometimes seen;

large gatherings

form

at feeding

family of their

and

they are classified

result,

own

—the

Eschrichtiidae.

breeding grounds; performs one of the longest migrations of any

Breeding

mammal

gestation period of 12-13 months. at

7-8 months; sexually mature

Gray whales take their name from the mottled

Weaned gray color of their skin. Their bodies are also

between

and 1 years. May live 50-60 years, maximum documented 77 years

covered with patches of orange or yellow

Rumbles, groans, whistles, rasps, chirps,

(160 kg) of barnacles attached to their

Voice

Barnacle Carrier

Single calf born about every 2 years after

moans, growls, and bongs

One

Small invertebrates scooped off the seabed,

Diet

including crustaceans, mollusks,

may have

barnacles; adults

type of barnacle

whale.

over 350 pounds

mainly on the

in clusters,

and worms

head and back. The barnacles breed Habitat

Shallow, coastal waters

between summer feeding grounds north in

easily find a

population found

Status

whale to

settle on.

Gray whales are one of the most parasite-

Chukchi and Bering seas and winter

breeding grounds off Baja California; smaller

this

group

off

Korea and Japan, but

lUCN Lower

all

Endangered (northwestern I.

Fairly

common

off

commonly

cetaceans. They are

infested with

close to extinction

Population: 20-25,000;

heavy of

whale

lice

—

small, crablike

crustaceans that cling to the whale's body. Risk:

Although the

sound

lice

nasty,

conservation dependent; Critically

CITES

at the gray

whales' calving grounds, so their larvae can

Distribution Pacific Ocean; main population migrates

Alaska

good

for the whale, since they

they can be

keep wounds

Pacific stock);

western U

clean by feeding on the decaying tissue.

Parasitic creatures are able to live

whales because species,

their host

on gray

slow-swimming

and the parasites do not get washed

off easily.

Whale

calves begin to acquire these

passengers just a few days after

birth.

Gray whales do not have a dorsal

on the

last third

found, which

of the back a low

SEE ALSO Whale,

Blue 3:98; Whale,

Humpback

3:102; Whale,

fin,

hump

bowed head

Bowhead

3:1 10

small

but

can be

followed by seven to eight

smaller ones. The

skin.

exclusive to the gray

can be found

WHALES AND DOLPHINS GRAY WHALE

ÂŁ

relation to the body, the

tail

fluke

deeply

notched, and the flippers are paddle shaped with pointed

Grays also have

tips.

much

whales are only found

shorter

baleen plates than other baleen whales because

small population occurs off Korea, but Critically

now

Endangered, having been reduced by

whaling to possibly fewer than 50 individuals.

Although they are

The eastern North

of collecting their Gray whales were

the Pacific Ocean.

they have a different feeding technique. filter

feeders, like other

way

baleen whales, they have a rather different

ÂŽ

around 300 years ago. Today gray

extinction

food from other species.

Instead of eating floating and

close to extinction. Whalers discovered the

breeding grounds

swimming

many

slaughtered

the open water, they feed

came

population also

Pacific

the late 1800s and

Numbers became so

whales.

was no longer

profitable to hunt

once the target of

organisms found

whaling ships. However,

on what they find on the seabed. They dive to

them, and they were

today the friendly giants

the bottom

whalers, the population began to recover, and

are a popular tourist

side.

They plow that side of

their

attraction, with

the sediment, then suck the

mud

thousands flocking to

stirred

watch their seasonal

muscular tongue

migrations along the

sediment out through the baleen

California coast.

strain off

shallow waters and

into their

mouth. Using

like a piston,

roll

onto one

left

became threatened when hunting resumed

their

with the introduction of factory ships

they force the plates.

They in

the

was hunted

increased. However, they

Then

early 1900s.

once again

the

1946 the International

Whaling Commission was formed, and with gray whales

listed as

Endangered, commercial

hunting was prohibited. They were able to reestablish themselves,

the North Atlantic,

but

alone. Free from the

that they have

There was once a population of gray in

left

numbers

with a mouthful of food.

whales

body through

any crabs, mollusks, or worms

process and are

low that

population

and the current

thought to be 20,000 to 25,000.

Long-Distance Journeys Moving between the warm waters where they breed and their cold polar feeding grounds, gray whales

make one

migrations of .

all

of the longest

mammals. The main

population of gray whales spends the

summer months

feeding

the cold waters of the Bering and Chukchi Seas.

With the

winter, the

start of

whales

â&#x20AC;&#x201D; SEA

MAMMALS

migrate south to warmer waters, where

When

breeding and calving take place.

to leave

another whale with them to help. The second

to get to

whale supports the mother, keeping her head

the

warm

waters to calve. They swim along the

West Coast their

First

who need

are the pregnant females,

America

of North

they reach

until

breeding grounds off Baja California.

Pregnant females

Laguna Ojo de

move

The warm,

calf to

first

milk

not survive

they were born

The lagoons are

the threat of

killer

after birth the

50 gallons (227 is

53 percent

70 pounds (27

the cold arctic

shallow lagoons the

from

bond with

its

â&#x20AC;&#x201D;conditions that

all

important

and the

can do

the

calf establishes a

builds is

The

its

calf will gain

to 32 kg) daily.

warm

strong its

layer of blubber

to survive the long journey

to the arctic feeding grounds

whales tend to avoid.

mother helps

mother, learns to coordinate

movements, and

whales, since they are

the

breath. For

of rich milk every day.

fat,

The calves could

also relatively safe

shallow with narrow entrances

few hours

will assist

its first

so alone. The mother provides the calf with up

the newborn calves, which only have a thin

seas.

the surface to take

her calf to the surface to breathe until

shallow waters of the lagoons are perfect for

layer of blubber for protection.

sometimes have

above the water and sometimes

the

into lagoons, such as

Liebre, to give birth.

giving birth, females

the spring.

Courtship Helpers

Friendly

Whales

the breeding season males and receptive

females swim together near the calving

/^^rays are extremely

inquisitive

the lagoons of Mexico

and is

friendly whales.

not unusual for a

gray whale to approach a small boat of people close

enough

for

them

to reach out

and touch

to enjoy having their backs scratched

and

it.

They seem

will

even

let

lagoons. During courtship they caress each

other with their flippers. Migration

mate

arrive at the

same

time.

breeding grounds at the

thought that mating

people reach into their mouths and stroke their

sometimes involve as many as

tongues. Although tourism must be monitored to

that

ensure

does not cause the whales

distress or

disruption, people's desire to see such magnificent

creatures

their natural habitat

produces support for

the continued conservation of the gray whale. Their affectionate character has gained

Friendly

and

them many

curious, gray

small boats in the lagoons around

people scratch

mouth

to stroke

friends.

coordinated so that whales that are ready to

swim and

roll

may

five individuals

around together. Researchers

speculate that the extra whales

mating

rituals

pair together.

may

hold the

Females are sexually

WHALES AND DOLPHINS GRAY WHALE

make the

entire migration north;

find areas

where they can

stay

some may

and feed

for the

winter without going as far as the arctic seas.

Tourist Attraction The coastal migration of such amazing animals is

now

major tourist attraction.

whale-watching industry

so lucrative that the

California gray whales are

the

In fact,

now

safe from

hunting. Thousands of people travel to see

them every

and there are whale-watching

year,

viewpoints at strategic places on

cliff

tops

all

along the coast of California north to Oregon

and beyond. The whales' high public offers

them

profile

a secure future, but hunting

not

the only danger. Noise pollution from the

engines of big ships could have an adverse during the long migration, and

effect, especially

the

dumping

sewage

habitat. Also, the very

into the sea spoils their

same

popularity that has

helped save them from hunting may cause too

much

disturbance, especially at their calving

grounds. The number of Californian gray

whales

currently fairly stable, but

be monitored to guarantee continued

needs to survival.

During migration and the breeding season gray whales eat very

ÂŠ

When

first

mother's help

support the

born, gray whale calves

calf

When

all.

They

their

on her back

until

number

winter

can breathe unaided.

weeks and probably

of different males.

over, the

whales migrate

The Right-Handed Whale

ray

whales feed mainly on small organisms that

live

on the ocean

floor.

To feast on the abundant

supply of food, they dive to the seabed, turn on their

north, back to the cold waters

where they can

side,

find plentiful supplies of food.

found that most gray whales turn on

north

the return

the recently impregnated females

that lead the migration;

last

to leave the

and suck up mouthfuls of

Mothers and calves remain

the

lagoons for as

The right-hand

left.

scarred since

become

feeding, but

as strong as possible for the long

Swimming

at less

than 5 miles

parasites

on that

side of the

means

their right-hand

head placed on the

become worn

body

often

covering about 50 miles (80 km) a day. The

human

when

that there are fewer skin

side. Their

onto the right side bias

has been

scraped along the ocean floor

also

per hour (8 km/h), they travel along the coast,

trip of

their

and are sometimes shorter than those on

faster

long as they can to allow their offspring to

journey ahead.

their prey.

seafloor, the right-hand baleen plates

down

at the

With that side of

side to feed.

breeding grounds are the females with calves.

yearly round

live

reaching the surface to breathe. She will

receptive for about three

mate with

may need

little,

preference for turning

feeding

rather like the

toward right-handedness.

some gray whales may be

12,500 miles (20,000 km). Not

all

whales

will

SEA

MAMMALS

the store of blubber that

When

under

lies

third of their total

may have

body weight.

up to one-

lost

during the

summer

long daylight hours of the arctic

air),

and breaching (leaping out of the water).

They sometimes wave

summer

the whales arrive at their

feeding grounds, they

their skin.

that

water, almost

a flipper out of the

greeting. Grays also

like a

produce a wide variety of vocalizations, including grunts, clicks, moans, knocking

and

whistles. However, their

sounds do

the gray whales do most of their feeding. From

noises,

about May to November they gorge themselves

not appear to be as complex or socially

on the abundant supply

of food that surrounds

made

important as those

by other whales.

them. They store enough energy to allow themselves to survive for the

Conflicts with Killer

the year.

rest of

The gray whale's feeding method, plowing

Whales

Despite being almost twice their

size,

gray

through the sediment to find food, may help

whales are sometimes attacked by

increase the productivity of the ocean, since

and many bear the scars of past encounters

from the seabed. The whale's

releases nutrients

specialized feeding technique allows exploit the seasonal

abundance

of food present

Although they are primarily bottom

ice.

feeders, gray whales will also

planktonic creatures and small fish out

open water column, that graze

large

among

the

killer

calf.

whales

will

an attempt to get to

Grays are strong animals,

whales are nevertheless a serious

swim away

have shown that grays

or try to hide

recordings of

of kelp.

and swim

the more active of the

whale

killer

when

will

they hear

vocalizations.

tail

fluke

into shallow waters:

the

When

the tide

goes out, unable to maneuver themselves back

become stranded on

to deeper waters, they can

head out of the water to look

around), lobtailing (waving their

separate the pair

the defenseless

killer

Whales sometimes become disorientated

whales and are often seen spy-hopping

(lifting their

try to

threat. Experiments

as well as the invertebrates

on long fronds

Grays are

most vulnerable. A pack of

but

sometimes eat

whales,

with these predators. Females and their calves are

floor after the retreat of the arctic

on the ocean pack

killer

the beach. Without the water's support large

whales are crushed by

own weight and

their

cannot breathe. Being coastal, the gray whale

The Rescue of Baby Gray

J. J.

the

ease

relatively at

appears able to survive such strandings. wait quietly for the tide to

n January

gray whale

Marina del

1997, a seven-day-old female baby

was found beached on

Rey, California.

It is

a seashore

possible that she

and

herself.

The baby was

taken to

SeaWorld, where she was named

memory

of Judi Jones,

member

been

J. J.

hours to survive. after she

J. J.

when

in,

are lucky

retreat to the shallows as a killer

whales.

predominantly coastal species, the

was extremely vulnerable

to the

whaling industry. Today their coastal habits help protect

the hard work paid off when, 14

was rescued from the beach,

all

may

to survive, but groups are able to

gray whale

had to be fed every three or four

All

come back

Not

defense against attacks from

prominent

it.

withstand a few hours out of the water.

of "Friends of the Sea Lion." Being such a

young whale,

months

who had

enough

will refloat

thought they may

her mother had not bonded, and that the stranded

baby then accidentally beached

the water

shallow waters and often

was

released back into the wild. During her stay at

them because they

tourist draw.

Many

creatures as they for

are such a

huge

flock to see the magnificent

make

the extensive migration

which they have become renowned.

SeaWorld she had gained about 7 tons (6.3 tonnes)

and grown over 18

ÂŠ A gray whale

feet (5.5 m).

whale then

SEE ALSO Whale,

Killer/Orca 3:62

will

fall

lift

calf breaching.

half or

back on

its

During breaching a

more of its body out of the

side into the sea.

water,

kT sl

jr***

\iS' l7-Â£

SEA

MAMMALS

Blue i

Whale

Balaenoptera

musculus

Scientific

name

Balaenoptera musculus

Family

Balaenopteridae

Order

Cetacea

Bigger than any of the dinosaurs, the blue whale

creature ever

on the

the largest

known

have lived

earth.

than male

Weight

14-136 tons (100-120 tonnes), occasionally

blue whale

up to 216 tons (190 tonnes)

Key features Long, streamlined

whale

rorqual

Weighing more than 20 African elephants, the

â&#x20AC;&#x201D;

earth.

largest

animal on earth; blue-gray with pale mottling; ridge runs along top of

flat,

The

gigantic

largest

â&#x20AC;&#x201D;the biggest animal on

known

dinosaur,

Argentinosaurus huinculensis, was about "U"feet (30

m) long and weighed

89 tons

(81 tonnes), but the blue

massive

shaped head; 2 blowholes with fleshy splashguard; tapered flippers up to one-

been known to

seventh of body length; small, stubby dorsal flukes broad

fin; tail

Habits

and triangular

Shy and wary; mother and

whale has 108 feet

attain lengths of

(33 m) and weigh nearly 180 tons (163 tonnes).

calf travel

pumps

heart the size of a small car

roughly

together, otherwise tends to be solitary;

sometimes

larger

numbers found

together feeding or migrating; with

Breeding

fin

6 tons (5.4 tonnes) of blood around the body. close

may

associate

whales

enough

mouth

Single calf born after gestation period of

10-1

Weaned

months.

sexually

mature

under 5 years

7-8 months;

at 5 years in

males.

May

human

live

In fact,

Loud, low rumbling

calls

Principally

krill,

80-100

team could stand

much

incredible sizes by will

come

in all

as a school bus.

grow to such

making use of the

feeding grounds. Their size

fertile

plentiful

polar

possible because

warmer their

grounds

tropical breeding

body

supported by water, and so they large, heavy,

and impractical

oceans of the world

bones that Status

The

on the tongue.

inside

supply of food present at their

closer to

do not require the Distribution Found

it.

so big that an entire

Blue whales have been able to

fish

polar feeding grounds and

and

to crawl through

whale

Abundant Food Supplies

shore to feed or breed; migrates between

subtropical

large

that travel long

but also other small

Mainly open ocean, but

the tongue alone weighs nearly 4 tons

(3.6 tonnes), as

crustaceans and

Habitat

for a

the dorsal aorta,

of the blue

football

distances underwater

Diet

artery,

females and just

years

Voice

The main

Population: 3,500;

lUCN Endangered; CITES

a land

animal of equivalent size

would need. Furthermore, support from the water

spread out evenly over the whole of

the whale's underside, not concentrated on the

bones of the hips and shoulders.

The blue whale has shape with

a girth that

adult right whale. But

a slim, streamlined is

less

when

than that of an

feeds the 80 to

100 throat grooves, which run from the chin to the navel, expand and increase the whale's

volume

SEE ALSO Whale,

more than

The mother and

Killer/Orca 3:62

calf

krill

and

this

unusual for the

may

explain

aerial

blue whale

killer

whales. After only seven or eight months the

birth

its

"company" with other

whale calves are

breeding

why some whales

view of a

and two

calves off the Pacific

coast of Mexico.

seem

to remain

available, they

all

year round: Since food

do not need

Big Appetites!

to undertake the

exhausting journey to the polar feeding grounds, hence saving precious energy reserves. Despite their

size,

When

swimmers:

blue whales are fast

quickly through the water, faster than

large body.

its

gorges

itself

its

polar feeding grounds,

krill.

At the

fertile

polar

waters the whales eat an estimated 3 to 3.6 tons (2.7 to 3.2 tonnes)

speeds of over 30 miles per hour (48 km/h).

them

he gigantic blue whale requires huge amounts of energy to sustain

taking advantage of the plentiful supply of

alarmed, they can reach

Their streamlined bodies allow

every day, the equivalent of about 40 million

move

most

krill.

Some

blue whale

populations fast once they leave the feeding grounds because there is

not such a plentiful supply of food

the

warmer waters where

ships.

But they rarely leap out of the water,

they breed. Also, they must dedicate their time to mating. Instead of

unlike

many

feeding, they obtain energy from their vast store of blubber

of their smaller relatives. They are

also timid,

which, combined with their

swiftness,

makes them hard

may weigh 54

to approach.

also surprisingly hard to locate

(fat)

that

tons (49 tonnes) per animal.

them, since they

tend to stay submerged for long periods, only surfacing for a diving for

few minutes

to breathe, then

up to 45 minutes. As

known about the everyday

life

a result,

little is

of blues.

Favored Catch

unable to catch

it,

its

enormous

size

advantage. Whalers were

so the species

was spared

the massive exploitation suffered by other

whales. However, the introduction of faster boats, improved whaling techniques,

and the

depleted stocks of more traditional catches led to the blue In fact,

up almost 90 percent of the whaling

whale becoming the favored

the animal's large size

strong motive to hunt

about 120 barrels of

it.

oil

now

target.

provided a

Whalers could extract

from

a single blue

made

industry's

total catch.

The slaughter peaked

when more

than 30,000 blue whales

to the whaling industry.

Before the mid-1800s the blue's

and speed were to

whale; and being so valuable, they soon

1931,

fell

victim

The International

Whaling Commission banned hunting of blue whales

much

1966,

when numbers had

that the species

influence of other

was

now

However, there are

declined so

close to extinction.

concerns about the

human

activities

ÂŠ

Blue whales usually

stay underwater for 10 to

on blue

20 minutes at a time

whales, such as pollution, habitat degradation,

before surfacing to take

and increased

a dozen or so breaths.

Some people low

levels of acoustic disturbance.

fear that

for a recovery to

be a tragedy

become

this

numbers have

happen.

fallen

would

too

certainly

phenomenal animal were

extinct because of

human

exploitation.

With each exhalation they spray a jet of water as high as 30 feet (9 m).

SEA

MAMMALS

Humpback Whale

Megaptera novaeangliae

and

Powerful, graceful,

playful, the

the gentle giant of the oceans. Scientific

name Megaptera

Family

Balaenopteridae

Order

Cetacea

songs,

ft (1

As well as being

Male

1.5-1 5 m).

also well

it is

The humpback whale

known

as the acrobat of the seas.

so called because

raises

generally slightly smaller than female

and bends

back

its

dorsal

About 34 tons (30

Key features

maximum 55

fin.

Its

preparation for a dive,

hump found

accentuating the

tonnes);

front of the

name, Megaptera, means

scientific

"giant wings" and refers to the whale's

tons (48 tonnes)

enormous

Large, stocky baleen whale; upper

body

flippers. In

an adult whale the

can reach 16 feet (5 m) long, equivalent

flippers

black or blue-black, underside white; long flippers;

raised

head and front edge of

lumps

different

Habits

social

called tubercles;

flippers

have

rarely

which narrows

large groups to

fluke.

feed and breed; moves individually or parties of

Breeding

One

produced every

May

months; sexually mature live

40-50

Complex underwater songs

Seasonal feeders on

krill

rapidly

toward the huge

tall

having fleshy bumps. These knobby lumps,

known

as tubercles, are found on top of the

head, on the lower jaw, and on the front edge

Weaned

4-6

years.

years, occasionally over

of their flippers.

consisting of

grunts, groans, rasps, twitters,

Diet

less

They are also unique among rorquals

of each,

Voice

length.

small

2 years after

gestation period of 11-12 months. at

2-3 within large groups

calf usually

body

have a more robust and

streamlined body than other rorqual whales,

than other rorqual whales, in

to almost a third of the total

Humpbacks

flukes

tail

every individual

seen alone; congregates

and

long, coarse hair

grows out

has been suggested that they

could provide an improved sense of touch.

and moos

(shrimplike

Parasite Host

crustaceans) and small fish

Humpback whales have Habitat

Oceanic; enters shallower tropical waters

rough, knobby skin.

bumps

cold waters the

winter for breeding

provide a

home

barnacles, which cannot attach to the Distribution Widely distributed; occurs seasonally

Population 30,000; lUCN Vulnerable; CITES

Uncommon and

for

smoother

in all

skin of other whales.

oceans and from the Arctic to Antarctic Status

One

species attaches

itself

deeply into the whale's skin so that only the I.

crown shows, while another

threatened

tubercles.

When

the

sits

on top of the

humpbacks move to

their

warmer breeding grounds, the barnacles drop off,

but

become

An is

where they were attached.

leaving scars

The whales are

their

now

fin

fluke

SEE ALSO

Dolphin,

Common

move

farther into polar ice

than most other rorquals.

up the Thames

106

will

estuaries, bays,

3:68; Whale, Blue 3:98, Whale,

River

One even swam

through the center of

Humpback 3:102

ÂŠ A minke whale

in a

London. Minkes also seem to

fjord in Antarctica.

The

baleen whales

from other

differ

that they are fairly solitary

whaler, Minke,

would frequently

fish for

were smaller than the permitted

that

time the small whales

came

whales

size. In

be known

northern animals belong

animals, being seen singly or

to the subspecies

aggregations can occur on feeding grounds.

Minke's whales. Later the

southern form.

Inquisitive Behavior

smallest of the rorquals. However, small size

(subspecies bonaerensis),

Minkes, unlike most rorquals, are inquisitive

also the

animals. They can often be seen spy-hopping:

the most abundant of today's rorquals. For

poking their heads above water to look around.

many

acutorostrata. The

often lacks a pale

its flippers.

scientists

in pairs.

Larger

band

regard these as

They

will

sometimes approach and

linger near

People on polar expeditions have been

separate species. Another

ships.

smaller southern form

able to approach and pat minke whales that

may be

have been trapped

either a

subspecies or species.

formally

given to the minke whale, since they are the

main

Some

name was

among

the pack

ice.

Minke

whales are also quite acrobatic and can leap out of the water relatively fast

travel

like a

dolphin. They are

swimmers and when

was

whale was the captivity.

only for a

first

few weeks,

can

was kept

a netted

named

much

them

larger species.

The minke only became economically attractive to the

numbers

whaling industry

of the larger species

when

began to

decline.

Threatened populations also began to receive whalers hunted the

unprotected minke. Today minke whales are

common.

Their population

between 500,000 and their

still

estimated at

million. Unfortunately,

abundance makes them vulnerable to

whalers

who want

the whaling ban

lifted

allow them to hunt minkes. Several thousand

area of sea, but soon escaped.

The minke whale

favor of the

quite

minke

rorqual ever to be kept

individual

years whalers tended to ignore

legal protection, so

startled

up to 19 miles per hour (30 km/h).

Although

main reason why the minke whale

after an

infamous 18th-century Norwegian whaler. The

are killed anyway, supposedly for scientific study, but they

still

end up

for sale as meat.

107

Southern Right

Whale

Eubalaena australis

Southern right whales are surprisingly acrobatic and Common name Scientific

name

Southern

whale % %

Eubalaena

Family

Balaenidae

Order

Cetacea

australis

playful for such rotund

and stocky

sometimes be seen raising

creatures.

the water.

(14-18 m). Female larger

The origin of the name southern right whale

than male

stems from the fact that whalers believed they

were the

some

"right" whales to catch. Unlike

thinner species

whose bodies

sink after being

harpooned, the large, stocky body of the (50-56 tonnes)

when

southern right whale floats

Key features

Stocky, rotund baleen whale; large

body color black to dark brown with

irregular

white patch on

belly; large flippers

are narrow at the base; broad

Habits

Single female

mated by

commonly found sometimes

12;

swimmers and

live

relatively

combination of such factors meant that they

even larger

were an

attractive target for whalers.

grounds

Knobby Growths As

mature

about 10

4-8 months; years.

May

sexually

live

a short, fat baleen

Diet

Tiny shrimp (copepods),

of arctic waters. Both species

have a large head that

typically a third of

length of the entire body. larval

whales have

cold antarctic seas; migrates

Southern Hemisphere;

mainly between 20 and 60Â°S

Status

Population: in total;

lUCN Vulnerable; CITES

similarities, right

a result of the (callosities)

may be fewer than 7,000

flippers.

Despite their

winter to warmer coastal waters to breed

Distribution Polar regions

addition, both

body coloring and

similar dark

broad flukes and Feeds

the

crustaceans,

and other small plankton Habitat

fin,

the southern right whale closely resembles the

bowhead whale

Burping noises and moans

whale with no dorsal

90-100

years

Voice

easy to hunt. The

but

gestation period of approximately 11-12

Weaned

meat, and

close to the shore, which

Single calf born about every 3 years after

months.

oil,

baleen. Southern right whales are also slow

makes them

groups of 2 or

at feeding

provides a plentiful supply of

fluke

several males;

groups of up to

groups may form

Breeding

tail

and

head

with lumpy projections: broad back, no dorsal fin;

dies

animals

actually

whales are

easily identifiable as

knobby outgrowths of hard their heads.

born with these

skin

The whales are

callosities already

formed on the upper and lower jaw, near the

blowhole, and above the eye. The most

prominent patch snout and

located on the tip of the

known

as the bonnet.

and barnacles inhabit the

Whale

callosities,

them appear white, orange,

lice

making

yellow, or pink.

Callosities are a useful aid to scientists, since

they are unique

shape and pattern. Individual

whales can therefore be recognized wherever they turn up and the

movements

of right

whales can be tracked across the oceans.

108