 Elephant
seals are the largest of all seals.
Males can grow to 4.5m long (15ft) and weigh
up to 4 tonnes (8800lb). Like fur seals, they show a strong sexual dimorphism
(difference in size between the males and females), females grow to about
2.8m (9ft) and 900kg (2000lb). A fully grown male and female side by side
are commonly mistaken for an adult and juvenile.
They are called elephant seals partly
because of their size and also partly because of the males snout or trunk
that he inflates to impress and intimidate rivals when competing with other
males.
This picture is of a male who has sustained
damage to his trunk during a fight. This makes him less able to compete
with rival males and so he was master of a very small harem of 2 or 3 females
rather than up to a hundred that the biggest and strongest males can command.
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 When
ashore and not competing with each other and when they don't have pups,
elephant seals gather in groups called "pods".
Pods are extremely smelly places! If the
wind is towards you, you know you are coming up to an elephant seal pod
long before you see it!
A diet largely consisting of squid that
is caught during feeding dives usually of 200 - 400m but sometimes up to
1500m doesn't do anything for the digestive system or your breath!
Most of the time pods are quite fairly
restful places in a constant snoring and guttural noise sort of way, but
every now and then one of the inner most seals decides it wants to go to
sea. Two tonnes or more of seal lumbering across his sleeping companions
causes quite a commotion.
Elephant seals spend only a small amount
of their time on land. Ashore they are cumbersome and great lumbering beasts,
in the water like many aquatic animals, they become lithe and graceful with
the blubber that made them ungainly on land becoming essential as insulation.
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 Elephant
seal pups are born in the Antarctic spring. Like many Antarctic seal pups,
they stay with their mother increasing rapidly in weight while the mother
gets progressively thinner. Eventually the mother has to feed and teach
the pup, by which time the pup is quite large and well developed.
The pups are very dark at birth and have
quite delicate flippers with long elegant nails that they scratch themselves
with quite precisely.
Weddell seal pups are like big mobile
unstuffed pyjama cases with the personality of a reckless 5 year old. Fur
seal pups are like small terrier puppies, bouncy and bold. Elephant seal
pups on the other hand are like little old men, very precise and somewhat
gnome-like, a stage that they grow out quite rapidly as they become teenagers
(in elephant seal years that is).
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4/ How friendly are Elephant seals? |
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 Antarctic
seals are generally completely unafraid of man despite the
inglorious days of sealing when hundreds of thousands of them were
killed fir their fur and/or blubber.
These days the recommendation is to stay
considerably further away than this, the small weaned pup in the
foreground has just his very close-fitting personal space invaded is
isn't that happy - he's not actually that bothered either to be honest.
The larger and older seals nearby seem completely unflustered.
The only time these seals get very upset
is if you approach them walking upright and normally. When they threaten
each other, they rear upwards to get as much height as they can and so
seem to assume that an upright figure is a threat. If you get down low
as this guy has done, they are pretty much unfrazzled, though by that
time you may be uncomfortably close to a ton or more of smelly,
sharp-toothed animated blubber.
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 These
are crabeater seals, probably the most numerous large mammals on earth after
humans.These are resting on
a large ice floe floating in broken summer ice near the Antarctic peninsula.
Though they are so numerous, it is unusual to see many crabeater seals together
as they live almost their entire lives on and amongst floating ice. For
this reason also, it is difficult to estimate their numbers, but by 2000
there were thought to be about 50 million.
Crabeaters are large seals of about 220kg
(484lb). They are frequently scarred, sometimes quite badly by predatory
leopard seals or killer whales.
Crabeaters are fairly solitary, and the
males and females are about the same size as the males do not need to be
large to compete for a harem of females as in elephant and fur seals.
The female gives birth on an ice floe
around September and suckles the young from a birth weight of about 20kg
(44lb) to 110kg (242lb) at weaning, this takes around a month. As with other
Antarctic seals, the female comes into oestrous very quickly and an attendant
male will mate with a female, seeing others off. After mating the male leaves
the female and goes to find another receptive female that he can mate with.
Many seals give the impression that they
form cosy family groups as they lay around together. The reality is usually
that it is a mixed group of individuals with no real bonds other than
between mothers
and their own pups.
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6/ Crabeater seals (Lobodon
carcinophagus) on ice floe |
 Female
Crabeater seals give
birth on an ice floe around September and suckles the young from a birth weight
of about 20kg (44lb) to 110kg (242lb) at weaning, this takes around a month. As
with other Antarctic seals, the female comes into oestrous very quickly and an
attendant male will mate with a female, seeing others off. After mating the male
leaves the female and goes to find another receptive female that he can mate
with. Many seals give the impression
that they form cozy family groups as they lay around together. The reality is
usually that it is a mixed group of individuals with no real bonds other than
mothers and their pups. Don't they have
some of the best scenery to look at though?! |
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7/ Crabeater seals (Lobodon
carcinophagus) on ice floe |
Crabeater seals on an ice floe.
Crabeaters are the most timid of the commonly encountered Antarctic
seals, whereas most types of Antarctic seal will lay there pretty much
oblivious to what's going on around them, crabeaters tend to be more
alert and are less easy to approach even if on an ice floe, they will
quickly display signs of nervousness and are inclined to slip into the
water and swim away. Crabeaters
often have scars on their bodies from close encounters with either
leopard seals or killer whales. |
 Crabeater
seals probably got their name because of a mistake by the early sealers
who went down to the Antarctic. They actually eat krill, the staple diet
of much of Antarctica's bird and mammal population.
In fact there are no crabs at all in Antarctic
waters, nor any other Decapod Crustaceans such as lobsters. No crabs live
south of the Antarctic Convergence.
Crabeater seals are uniquely adapted amongst
seals in that their teeth are adapted to form a sieve in a similar manner
to the baleen plates of the great whales. They take a mouthful of seawater
and krill and expel the water through gaps in their teeth while the parts
that overlap prevent the krill from escaping.
Each seal consumes about 20kg of krill
per day, and a quick bit of maths calculates that between them, crabeaters
eat 1 million tonnes of krill per day! That's an awful lot of little shrimps!
Crabeater seals are circumpolar living
all around the edge of the Antarctic continent.
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9/ A Leopard seal |
Named for the spotting on its underside, the Leopard Seal
is one of the largest predators in Antarctica, smaller only than the killer
whale. Females are larger than males and average about 3m (10ft) long
and around 350kg (770lb). They appear more squat when on the surface as
in this picture on an ice floe, where they are nearly always seen, only
rarely coming ashore onto land. In the sea, they appear longer, sleeker
and almost snake-like in form and movements, though they swim of course
with fore and hind flippers.Leopard seals are built
for speed, they have a large powerful head, a huge gape and a massive lower
jaw. They frequent the edge of the pack ice and in particular areas around
penguin rookeries all around Antarctica. They are fairly opportunistic as
predators and will east a wide variety of prey from krill to penguins to
young crabeater seals - their main prey. Their teeth are very much those
of a carnivore, though they are also partly adapted with three large cusps
on the pre-molars and molars that interlock and are also able to act as
a strainer when feeding on krill.
They are inquisitive and fearless, frequently approaching
small boats to investigate when their large "grin" and all of those teeth
they have can make them appear quite menacing.
Their way of dealing with penguins is quite gruesome.
Once caught and killed, the penguin is shaken violently from side to side
by the leopard seal until it is literally thrown out of its skin and feathers
for the seal to then swallow. Floating penguin skins in the sea are a sure
sign of leopard seals nearby.
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Antarctica Fact File Index
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