Penguins
There are 17 species of penguins some of which are found as far north as the
equator. Penguins are categorized into three families: brush-tail,
crested, and king/emperor penguins. Of the 17 species only six are found in
Antarctica (Adélies, Chinstraps, Emperors, Gentoos, Macaronis, and
Rockhoppers).
Penguins often are referred to as "flippered flyers" due to their effortless
movement through the water and their possible evolution from gull-like
birds. Its believed that 40-50 million years ago, while Antarctica breaking
away form Gondwanaland, penguins also were separating to form their own
species. Originally, indigenous to warmer climates, penguins adapted to the
cold as Antarctica made its move southward.
Part of their adaptation to the cold includes oily, unwettable feathers
which cover the outer layers of penguins (and what gives that distinguished,
well dressed look). Underneath is a layer of soft down feathers and under
that a thick layer of fat. This keeps the penguins so warm they will
actually fluff their feather to released trapped heat in order to cool
down.
In addition to their fine attire, penguins are well known for their
swimming abilities. Using their flippers for propulsion and their feet as a
rudder, penguins can swim in excess of 12 mph (20 kph). Through the use of
air sacs to protect their lungs, penguins can stay under water for 15 to 20
minutes and dive as deep as 275 feet (900 meters).
In the water, penguins typically feed on krill and fish. The dietary
habits of penguins are relatively easy to monitor. Krill eating
penguins excrete pink quano, while those eating fish leave behind white
guano. The yolks of penguins eggs often are red denoting the
consumption of krill.
Although very near-sighted on land, penguins posses exceptional vision in
the water. Their eyes, like the many sea animals, are attuned to the colors
of the sea--green, blue-green, and violet. They need this excellent vision
to avoid leopard seals and killer whales, which are their primary predators
in the ocean. On land their arch enemy are skuas (large birds) which snatch
penguins chicks from nests.
Adélie Penguins
Adélies were named after the wife of the English explorer Dumont d'Urville.
They are relatively small birds standing on average 27.5 inches (70
centimeters) high and weighing 10-11 pounds (5 kilos). During the harsh
winter months they stay near the outer edges of the pack ice where
temperatures are slightly warmer. As summer approaches, they migrate
towards the continent and form rookeries ranging in size from under a
hundred to hundreds of thousand.
Males arriving first attempt to reclaim old nesting spots. Females are
presented with pebbles as gifts during the courting process. Adults
surviving from one year to the next often mate again. However, this
marriage is not permanent; pairs typically separate after five or six
years.
Immediately after laying her eggs (there's typically 1-2 eggs) the female
heads for the open sea to replenish her food storage. The male incubates
the eggs for the first 10-15 days while the female is away. Upon her
return, the male spends 10-15 days at sea fatten up. The male eventually
returns to take the final shift of 3-7 days. During the whole courtship and
incubation period, mates will lose up to 45% of their initial body
weight.
Chicks stay with their parents for approximately three weeks during which
they grow rapidly. After that, they join the other chicks in nurseries
called créches. At that time, both parents go to sea to feed. This is the
most dangerous time for a chick, skuas circling above continuously raid the
nursery for fatten chicks. After four weeks of age, the chicks head for the
sea. By late February, the colonies are abandoned.
Chinstrap Penguins
Chinstraps get their name from the thin line which circles from behind one
eye under the chin to behind the other eye, much like a strap on a helmet.
They are the same approximate size as Adélies, 27 inches (68 centimeters)
high and weighing 10-11 pounds (4.5-5 kilos).
Chinstraps appear to prefer slightly warmer waters, only breeding among the
islands off the coast of the Antarctic Peninsula. One of the largest
colonies, Bailey's Head, is located on the side of a currently dormant
volcano called Deception Island. Estimates place the size of this colony
between 500,000-1,000,000+ Chinstrap penguins.
Chinstraps prefer higher, rocky terrain to nest; and although they are
similar in size and appearance to the Adélies, Chinstraps mating practices
are more aggressive. Early arriving Chinstraps vie for those nest sites
free of snow cover. Later arriving males may even drive off nesting couples
in order to acquire their site. Once securing a nest, the male waits for
his mate from the previous years. If she doesn't arrive in five days, he'll
mate with another female. If the original female mate does show up, the
guano hits the fan! A battle ensues with the losing female occasionally
being tossed down the hillside of colony.
Once the eggs are hatched, feeding duties are shared by the pair. After
nine weeks, Chinstrap chicks are ready to leave the colony for the open
ocean.
Emperor Penguins
Emperor penguins are the largest of all penguins. The average 44 inches
high (1.15 meters) and 66 pounds (30 kilos) in weight. Emperors also are
the most colorfully outfitted species. Although they are the least numerous
of all species, breeding colonies in excess of 100,000 have been found.
Emperors undergo the most stressful breeding process of all penguins. The
breeding season for Emperors begins at the start of the Antarctic
winter--late March. As winter approaches, Emperors actually move inland to
their traditional colonies and begin pairing. An Emperor seeks his/her mate
from the previous by wandering through the colony making bugling call. Upon
finding their mate, each penguin repeatedly bows to the other while
continuing its bugling and flashing the orange patches on each side of its
head.
Eggs begin appearing in May (at northern colonies) and late-June or July (in
southern colonies). Almost all of the eggs in the colonies are laid within
2-3 weeks of each other; each couple laying only one egg. To keep the egg
from freezing on the ice covered ground, Emperors balance the egg on the top
of their feet while lower their body over the top of the egg as a
blanket.
Almost immediately after the egg is laid the female heads for the open sea.
She remains there for two months, feeding. The male, having not eaten for
the two months during the courting process, incubates the egg for two more
months while the female is away. During this time, the males huddle
together in a large mass to stay warm in the midst of brutally cold
temperatures--all the while balancing the egg on their feet.
Females return at the approximate time the chicks are hatching. At this
time, females take over feeding the new born chick while the male leaves to
restore his food supply. After three to four weeks, the male returns to
assist in the feeding. At seven or eight weeks of age (typically in
November/December), the chick are large enough to leave their parents and
head for the sea. Over 75% of Emperor parents successfully raise a
chick.
Gentoo Penguins
Gentoo, meaning "turban", refers to the whitish markings behind the eyes of
this species. Gentoos range in size from 27 inches high (68 centimeters)
and 12 pounds (5.5 kilos) in the south to 30 inches high (71 centimeters)
and 13.5 pounds (6.2 kilos) in the north. The 60 degree parallel marks the
general separation point between the Gentoos' north and south ranges.
Most of their colonies run along the Antarctic Peninsula. Unlike the
Adélies and Chinstraps, Gentoos stay with their mates throughout the year.
A mating pair may reuse a previous site, although they typically change from
year to the next. Gentoos commonly locate their nesting sites inland. To
ease their burden walking to and from the sea, Gentoos establish a common
path for everyone. This continuous use wears down the path and makes it
easier to use.
Gentoo chicks stay with the parents for about eight weeks. During their 9th
and 10th weeks, chick return home at night to be fed. Should the mating
pair lose their first clutch of eggs, a second set is laid if
earlier enough in the season.
Macaroni Penguins
Macaronis earn their by the ornate yellow plumage above each eye. They were
named after flamboyant dressers in the 18th century who were called
"Macaroni Dandies"--just like in the song "Yankee Doodle".
Macaronis are similar in size and stature to the Adélies and Chinstrap
penguins. On average, they stand 27.5 inches tall (70 centimeters) and
weigh 9 pounds (4.2 kilos). Their typically frequent the island around
Antarctica and don't venture onto the main continent. Their largest
colonies are found in South Georgia and Heard Island.
Breeding season for Macaronis begins in December when mating pairs lay two
eggs. The first typically is half the size of the second egg and rarely
does the first egg produce a chick. The larger egg incubates for
approximately 35 days. After the chick hatches, the female goes to sea and
periodically returns with food for the family. After a couple of weeks, the
chick is large enough for both parents to collect food at sea. By March,
the chick generally is large enough to leave the colony.
Rockhopper Penguins
Rockhoppers are the smallest of the penguins in Antarctica. They measure only 21.5 inches high (55 centimeters) and weigh only 5.5 pounds (2.5 kilos). Similar to Macaronis, Rockhoppers have a feathered crest on top of their heads.
Although frequently found among Macaronis, this specie is much more
aggressive. Their colonies are found among rocky slopes of islands out
near the Antarctic Convergence. Two eggs are typically laid, one smaller and one larger.
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