CoimbatoreTaxi News
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
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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