The Wild Side Page #3

---

dolphins in Shark Bay

only a handful of females

have mastered this technique

Often dolphins play with

their catch before eating it

Just offshore a dolphin tosses

a snake eel about like a ragdoll

The others approach the tossed

prey with great interest

But they will not touch it

observing some kind of protocol

Scientists have speculated

it's a way of confirming

trust or simply avoiding

a costly conflict

When calves catch their tiny fish

they too make a great show of it

By five or six years old

young dolphins no longer

need their mother's guidance

They will be part

of a hunting culture that will

forever be as

challenging as it is perilous

Dolphins have

adapted to an alien world

that is hostile

to air-breathing mammals

In the dark of night

dolphins need to

know what's out there

Using their echolocation

dolphins can detect the size

shape- even the

density of an object

But it's only

good for a hundred yards

or so and is

highly directional

detecting nothing

from behind

It's so accurate

they can clearly

distinguish between

different species of fish

Even in daylight

visibility is limited underwater

But using sonar can

be risky because the

tell-tale clicks may reveal

your presence to predators

So dolphins rely more on

their excellent hearing

The best defense is to stay together

keep silent - and listen

Success in hunting is knowing

when to use your sonar

and when to turn it off

With its own

sonar turned off

a killer whale moves silently

through Alaskan waters - listening

It can hear the

slightest splashing

the very breathing

of distant prey

A group of Dall's porpoises

just up ahead

These are among the fastest

small cetaceans

so quick and agile they can

elude most predators

They travel these icy waters

in groups of two to ten

But for this small herd there's

little safety in numbers

As quietly as possible

the killer whales

are closing in

The slightest sound would

betray their presence

The porpoises

detect something

But it may be too late

The killers are capable of

speeds up to thirty miles per hour

The porpoise zigzags

for its life

Killer whales are masters at

cutting off the path of retreat

This one dives below

a harbor porpoise

Like sharks

killer whales don't always

finish off their prey

right away

They'll often let

the victim struggle until

it's energy is spent

or it simply bleeds to death

Other members of the pod

move in on a

Dall's porpoise that's

been hit

It still has some life

left and

tries to make it

to calmer inshore waters

The males- like lions tend to

leave the hunting to the females

Now they join

in for the kill

Soon the restless

seas are resonating

with the eerie calls

of the killers

and the chilling sounds of

teeth crushing bone

The porpoise had the

unhappy fate to be pursued

by hunters with sensory

capabilities as good as its own

For killer whales

are dolphins

They are the largest

member of the family and

the only dolphins that

habitually hunt their cousins

Still, they're the most

sociable of all dolphins

living in highly stable

family groups

Most of the males never leave

the group they are born in

Some will even teach

the calves how to hunt

This unfortunate

harbor seal is about

to become a living

training tool

The killer whales circle the prey

as if toying with it

In fact

they may be demonstrating

to their young how to

cut off a prey's retreat

or how to confuse it

More important the

calves will learn how to

coordinate their efforts

with others in the pod

Older males have been observed

allowing calves to feed

before they themselves

begin to eat

The young will grow into

the ocean's top predators

Like killer whales, pilot whales

are misnamed and are true dolphins

The second largest

of the family

they can weigh up

to four tons

Pilot whales dive to

depths of a half mile

in search of octopus

and squid

These pygmy killer

whales may be every

bit as fierce as

their namesakes

And like their bigger

cousins, they're

believed to kill

marine mammals

But pygmy killers are very rare

and seldom observed in the wild

There are over thirty

species of dolphins

and we know very little

about most of them

The northern right whale dolphin

is a gregarious

creature often found

swimming with other species

like white-sided dolphins.

Dolphins come in a

variety of sizes and shapes

What distinguishes

them as a family are anatomical

features like the shape

of the jaws and teeth

Dolphins are designed

for the hunt

This fifty ton monster

is a grazer not a hunter

And it's a true whale

Southern right whales

are filter feeders

straining enormous quantities

of water for tiny crustaceans

The windswept shores of

Patagonia in Argentina

Once a year

right whales migrate

to breed in the warm

shallow waters

Here they are greeted

by dusky dolphins

Unlike their big

lumbering cousins

duskys are small

fast, and agile

In the summer months

they leave the safety of coastal

waters to hunt miles offshore

In deep waters, locating

pursuing and catching prey

is exceptionally difficult

But duskys have developed

some extraordinary tactics

In the morning, small

search parties set out

probing with their sonar

There may be twenty to thirty

groups patrolling these waters

each pod separated

by a mile or two

The leaps give them a vantage

point for sighting prey

Seabirds have gathered up ahead

a sign they've found something

This time of year Southern

anchovies are here in vast numbers

For the penguins

it's a feast

It's up to the dolphins

to bring some

order to all this and

they quickly do

The dolphin's strategy is to

circle the school

and drive it into an

ever tightening ball

They guard the outside

perimeter by blowing bubbles

which frightens the fish

This takes advantage of

the fishes' natural defense

to huddle together

when attacked

As the fish ball

gets tighter

the duskys take turns

grabbing mouthfuls

of fish then retreat

to guard the perimeter

Soon the ball is

clustered so tightly

the fishes' escape

response breaks down

Now it's simply a

matter of the

dolphins' nipping food

off the edges

As the feeding progresses

the dolphin calves

are nowhere to be seen

For others drawn

to the feast might prefer

young dolphin to

a mouthful of anchovies

Mothers bring their calves

to a sort of nursery

away from the chaos

of the feeding area

For the rest of the group

the feeding's over

and it's time to celebrate

The event is marked by

exhilarating acrobatic displays

Dolphin groups that

usually travel

apart now come together

to socialize

In the world of dolphins

that means

frequent sex with a variety

of partners

The males- swimming upside down

follow the females

They synchronize their

movement with hers

all for a brief moment

of coupling

Physical contact among

these groups of

dolphins strengthens

communal bonds

For cooperative hunters

Rate this script:0.0 / 0 votes