|Emperor penguins are
one of the "classic" penguin species that people imagine when they hear
the name. Along with King Penguins and
Adelie penguins, they are representative
of the whole group.
Emperor penguins have
the upright and regal bearing that their name suggests. They take the
dinner-jacketed formality of all penguins to its highest level and though
they are able to be as awkward, gawky and get as dirty as other penguins,
when they shake it all off and stand up to regain their dignity, there
are few if any more stately and elegant animals on earth.
Emperor penguins are the largest of penguin species
with an average weight of around 30kg (66lb, but can be up to 40kg (88lb))
and a height of approx. 1.15m (3.8ft).
They have colourful feathers around their necks and
heads, though are not quite as bright as king penguins which are almost
as large. There is little or no possibility of confusing the two species
however as their distribution around Antarctica is very different. While
king penguins are a sub-Antarctic species, being based on islands dotted
around the continent, emperor penguins are animals of the deep south.
Emperor penguins have yellow ear patches that are
"open" fading into the white of the breast feathers, whereas king penguins
have orange ear patches that are "closed" by a band of black feathers.
Emperor penguin chicks have distinctive plumage with a large white face
All but 2 of about 40 known emperor penguin colonies
are on winter fast ice that is frozen solid and attached to the land
from autumn until it begins to break up in the spring (though some years
it doesn't break up at all). They are found all around the coasts of
the Antarctic continent. They breed during the depths of the Antarctic
winter and in some of the most desolate, coldest, windiest and downright
grim places on the planet during the season of 24 hour darkness. Some
emperor penguins are therefore the only birds that never set foot on
The first breeding colony wasn't discovered until 1902
by Lt. Reginald Skelton on Scott's 1901-04 Discovery Expedition
some 130 years after the birds had first been seen on Captain Cook's
second voyage. New colonies were still being discovered as late as
Early in the 20th century, Emperor penguins were thought
to be some kind of evolutionary "missing link", something that scientists
thought could be proven by observing the growth of the embryo at various
stages. On Scott's 1910-1913 Terra Nova expedition a small group of
expeditioners set out on a winter sledging journey led by Wilson, the
biologist and including the young Apsley Cherry-Garrard, famously this
gave rise to the acknowledged greatest of all Antarctic adventure and
travel books "The
Worst Journey in the World".
Emperor penguins feed on fish, krill and squid which
they catch on dives that are longer and deeper than any other penguin
or bird species. They can dive to a depth of 1,800 feet (550 meters)
and hold their breath for up to 22 minutes. This allows them to reach
and exploit food resources that other birds can't reach.
The diving abilities of emperor penguins has been
widely studied, they have been found to have:
1/ an increased ability to store oxygen in the body
2) the ability to tolerate low levels of oxygen in the body
ability to tolerate the effects of pressure.
Emperor penguins tolerate low levels of oxygen during
dives that would cause a human to pass out and they experience pressures
so great that we would get the bends. Neither of these things seem to
adversely affect penguins. Their diving physiology is studied at McMurdo
Station at a place called
ranch 15 miles out in the sea ice where there is only a single hole
in the ice, so the penguins must return there to leave the sea.
A penguin's normal resting heart-beat is about 60-70
beats per minute (bpm), this goes up to 180-200 bpm before a dive as
they load up with oxygen, then as they hit the water, the rate drops
to 100 bpm immediately slowing to only 20 bpm during most of the dive
so they use the stored oxygen in blood and muscles to the maximum effect.
On returning to the surface again, the heart rate goes back to 200 bpm
probably to pay back the "oxygen debt" they have incurred during the