An Emperor’s TaleBy Ellen Lambeth; photos by Stefan Christmann/NPL.COM
It’s the middle of winter in the coldest place on Earth. But somehow, new life is just beginning.
The emperor at the center of this tale isn’t really royalty. It’s a bird called the emperor penguin. But it is the world’s largest penguin. (An adult may stand about as tall as a 7-year-old kid.) So, being called the emperor of all penguins sounds just about right.
Emperor penguins spend their summers swimming in the Southern Ocean around Antarctica. There they find plenty of their favorite foods: squid, fish, and tiny shrimplike creatures called krill.
As summer fades to fall, the seawater around Antarctica starts to freeze into a sheet of ice (see map). The ice sheet grows farther and farther from land as fall turns into winter. (Don’t forget that the seasons at the bottom of the world are the opposite of those at the top. So, down there, fall begins in March.)
By April, the emperors leave the water and start a long journey across the frozen sea toward the edge of Antarctica. They can’t fly, so they must “march” many miles over the ice, where they finally settle in large groups called colonies. Each colony may be made up of thousands of birds! And then the magic begins.
Fall is “getting to know you” season for emperors, with males and females pairing off as couples. The birds in each pair waddle and hum, stretch and bow, and gaze at each other until they decide they’re a match. Then they mate. The next job is laying the egg. Neither bird makes a nest. The female just lays her single, delicate egg.
Remember, it’s almost winter and extremely cold out there on the ice! As quickly as he can, the male moves the egg onto his feet. Under his belly is a flap of bare skin called the “brood patch.” Tucked between that and Dad’s feet, the egg will stay warm and safe.
DAD ON DUTY
Neither Mom nor Dad has eaten since their summer feeding. Mom used up a lot of energy making and laying her egg. Now it’s time for her to get back to the open ocean to fill up again. Meanwhile, Dad stays behind at the colony with all the other dads.
Winter at the bottom of the world is a blast—and not in a fun way. Bitter winds blow, and temperatures may drop to 60 degrees below zero! The sun barely peeks above the horizon, so it’s dark both night and day. Blizzards are not uncommon. Brrr! But through it all, the egg-carrying dads stick together and keep each other company. They also keep each other warm by forming a huddle.
BUILT FOR WINTER
Even summers are cold in Antarctica. The temperature there almost never gets above freezing. The ocean waters are frigid, too. How do these birds survive?
Being big helps. (Small bodies lose heat more quickly than large ones.) And after feasting all summer, each bird has an extra-thick layer of fat under the skin. The skin is covered with tightly packed, overlapping feathers—about 80 per square inch. These keep out the harsh wind and bitter-cold air. (They also keep out icy water when the bird swims.) And between those feathers and the skin is a layer of soft, fluffy feathers called down, which helps hold in body heat.
Even though emperor penguins are perfectly suited for their environment, it’s still not an easy life. While the females are off feasting, the males are on round-the-clock nursery duty. They can shuffle around a bit but can’t really go anywhere. (Try walking with an egg balanced on your feet and see how far you get.)
If a blizzard whips up, the males huddle together in a tight circle with their backs to the wind. Believe it or not, the birds in the middle can get too hot, so they all constantly trade places. That way, no one bird stays too warm in the middle or too cold on the outside.
After two months, the eggs start to hatch, right at winter’s peak. Each dad has lost close to half his body weight but can cough up some food-like substance into his chick’s begging mouth. That will work for a little while.
Around this time, the females return to the colony after their ocean feasting. They find their mates and reclaim their chicks. Each chick has only a thin coat of fuzz, so the pass-off is as quick and careful as the egg pass-off was. Finally, Dad returns to the sea to “refuel” while Mom takes over. She now has plenty of food stored in her belly to feed her chick.
As the chicks grow, the parents trade places more often. The adults form long lines going back and forth across the frozen sea to reach open water and food. Soon, each chick grows a thicker, fuzzier coat, so it doesn’t have to sit on its parents’ feet anymore. The chicks are too big for that now anyway!
By December, the Antarctic summer arrives. The sun stays up both day and night, melting the sea ice, which helps make the parents’ feeding trips shorter and faster. The chicks are bigger, and their waterproof feathers are growing in.
Soon, the parents will head into the waters and not return. When the time is right, the chicks will take their first dives into the sea, which should be right at their feet by then. Without any parents around, they must learn on their own how to swim, catch a meal, and avoid hungry predators such as leopard seals.
One danger they can’t fend off is climate change. Warmer global temperatures mean Antarctica’s ice sheet won’t grow as wide or as thick. It’s also slower to form in the fall and quicker to melt in the spring. This throws the penguins off the schedule they’ve lived by for many thousands of years.
But with luck, these chicks will survive the ocean’s dangers and the changing climate to someday raise emperor families of their own.