Childrens Illustrated Encyclopedia

Whales and dolphins

567

Echolocation

in addition to using their sight and

hearing, dolphins are able to sense

other creatures nearby by means

of a special organ in their forehead

called the “melon.” By making a loud clicking

sound that bounces off objects and makes echoes, the

dolphin can tell the size and distance of another creature

in the water. it can then warn other dolphins of any danger.

world Wonders of the ancient

all whales and most dolphins live in the sea; four kinds of dolphins

live in rivers. some whales, such as the humpback whale, inhabit

all oceans; others, such as the narwhal and the beluga whale, live

only near the arctic region.

BiggEst animal EvEr

Blue whales are larger than

the dinosaurs were—up to

100 ft (30 m) in length. they

are the heaviest animals ever,

weighing 134 tons—about as

heavy as 2,000 people.

migration

many whales spend the

winter in warm seas and

the summer in colder

waters, traveling great

distances from ocean to

ocean. gray whales travel

south to give birth to one calf in

the winter near california. then the

mother and baby begin a long journey

up the coast toward the Bering sea and

the arctic ocean.

Killer whale (orca) 25 ft

(8 m), 3.5 tons

Humpback

whale 50 ft

(16 m ), 26 tons

strandings

Whales sometimes swim too close to

the land and are stranded. Without

water to support their bodies, they

cannot breathe and soon die.

Blue whale

Right whale

Humpback whale

spErm WhalE

the impressive sperm whale is the deepest-diving

sea mammal known to us. it swims down to at least

2,000 ft (600 m), holding its breath for more than an

hour. measuring more than 50 ft (15 m) in length, it is the

largest of the toothed whales and has enormous teeth—up to

10 in (25 cm) long—on its lower jaw. the sperm whale feeds on

squid and fish deep down near the seabed. in the past, so many

sperm whales were killed to make products from their fatty

blubber, flesh, and the oil in their foreheads (spermaceti)

that very few of these great creatures now exist.

thE largEst Brain

the brain of the sperm whale is the

biggest of any animal, weighing

more than 20 lbs (9 kg).

Up to 50 teeth in lower jaw

Outgoing clicking sound

and returning echoes

Bering Sea

Shark is detected

by a dolphin

BloWholEs

after a dive, whales rise to the

surface to blow out warm, moist air

from their lungs. as this air mixes

with the cold ocean air, the moisture

condenses (like your breath on a

cold winter morning). this is what

makes the watery-looking spout.

Sperm whale

Melon organ

in forehead

WhalE sounds

Whales make a variety of

sounds, including squeals,

groans, yips, and wails, which

carry many miles through the

water. Each male humpback

whale has its own song, lasting

for up to 35 minutes, which it

sings over and over again.

dolphins in a group “talk”

constantly to each other

as they play and feed.

The sperm whale’s

enormous forehead

is filled with a waxy,

oily substance called

spermaceti, which

helps keep the whale

upright in the water.

Canada

Beluga, 1.5 tons

Ganges river

dolphin, 200 lbs

(90 kg)

Narwhal,

1.5 tons

Pacific white-

sided dolphin,

200 lbs (90 kg)

Human

diver, 6 ft (2 m)

in length. Blue whale

100 ft (30 m) in length.

United

StateS

California

Find out more

animals

animal senses

mammals

migration, animal

ocean wildlife

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