Emperor Penguins

On being an Emperor Penguin

Did you know that winter temperatures here in Antarctica can drop down to -58°F (-50°C) with sustained winds blowing at 124 mph (200 kph)? 

By your standards, that’s jolly cold. Jolly cold, indeed! But we emperor penguins are rather built for this kind of weather. We have two layers of feathers which offer us exceptional insulation to keep out water and wind. And that plumage extends down our legs, so our ankles don’t catch a chill. Even our feet contain special fats that prevent freezing and our strong claws help grip the ice.

By the way, I’m Nevan (he/him). We emperor penguins have devised a cooperative community that allows us to live in a cold and icy world. Another staple in our lives is that we split our time between the ice and the sea. And on the auspicious occasion of me approaching my thirteenth year, if you’ll allow this old fellow a moment, I’d love to tell you all about the annual cycle of our lives that encompasses these two very different places.

Journey to the Center of the Molting Grounds

At Sea (mid-December through January)

(A special note to my friends in the Northern Hemisphere to not forget that our seasons are the reverse of your own.)

Around December, as our weather warms and the ice melts, the sun brightens our skies for nearly 24 hours a day. It is at this time that I take to the sea. I dive in and hightail it 65 feet (20 meters) from shore, then take a moment to groom myself. I roll back and forth, flapping my wings at my side until my feathers are all preened and looking snazzy. And then, all the adults in the area depart en masse. We swim for the next month, traveling 29 miles (47 kilometers) each day until we reach our molting grounds hundreds of miles (over 1,000 kilometers) away.

As we travel, we gorge on Antarctic silverfish, krill, and squid. To find a meal, I dive 500 – 800 feet deep (150-250 meters) and am underwater for three to six minutes. While I more commonly nosh four to six pounds (two to three kilograms) each day, when I need to gain weight, I up the ante to thirteen pounds (six kilograms). The latter applies to us now as we must each gain about 22 pounds (10 kilograms) to survive what comes next.

I’ll Stop the World and Molt with You

On Sea Ice (February)

Our journey takes us to a concentration of large ice floes that serve as our molting grounds. Over the next month, we go through a catastrophic molt where our whole-body sheds, with new feathers pushing out all the old feathers. During this process we are no longer waterproof and must remain dry to avoid hypothermia. Over the month we must remain on land, we are forced to fast and may lose half our body weight. This is becoming an increasingly dangerous period for us because the sea ice is breaking up earlier each year and some of us may be forced into the water before our new feathers have fully grown in to protect us. 

Homeward Bound: The Incredible Journey

Back At Sea (first part of March)

With our new feathers looking fabulous, we all head back to the colony. We move as a flock, scooping up as many fish and krill as we can in the process. We must gain weight to get back into mating form.

March of the Penguins

On the Ice, Ice, Baby (mid-March through mid-April)

As winter begins in Antarctica, the sea freezes up to form a thick layer of ice that runs nearly 70 miles long. Unfortunately, any storm can cause this ice to shift. Because our colony requires more stable ground, we must head further inland.  

At the beginning of our journey, we all occasionally take a break from walking and instead slide on our bellies while pushing with our feet. As we continue our trek, though, we fall into perfect alignment. Imagine, if you will, hundreds of us penguins marching single file down a penguin highway, each stepping into the tracks left by the penguin before them. No one tries to pass anyone else. As we move, our upper bodies sway slightly from side to side. Our wings are pressed close to our sides for added warmth.

We walk day and night to reach our breeding site, returning to the place we were born for this momentous event. As we arrive, there are columns of penguins coming from all directions.  At this juncture, I weigh a stately 88 pounds (40 kilograms) and am in peak form for the mating game.

The Mating Game

Still on the Ice, Ice, Baby (late April)

Each year, I find a new mate to whom I devote myself for the coming season. We males take turns singing as we strut up and down the breeding ground in a most impressive manner. When it’s my turn, I trumpet my call for about two seconds and then raise my head to listen. When there is no response to my wooing call, I growl and continue walking. I give others in my group a chance to sing their own song and then it’s my turn again. 

This time, after I sing, I receive a response from Penelope. She joins me on the edge of the colony, and we decide we’re a match made in heaven. We stop singing and stand close to each other with our eyes closed.

Over the next several weeks, Penelope and I bond. We enjoy many games of copycat, which allows us to synchronize our movements. And while we await the big event, we rehearse how we will transfer our egg from Penelope’s feet to mine using a chunk of snow. It is critical that we get this down because our chick will die if the egg spends more than 60 seconds on the ice.

An Eggsellent Development

It’s as Cold as Ice (May through July)

In the first week of May, Penelope lays our single egg, which is roughly the size of a grown human’s fist. She remains standing throughout and because we cannot build a nest on the ice, she balances our progeny on her feet, tucking it into a special brood pouch to keep it warm.

After a day, in our first real test as a bonded pair, Penelope prepares to transfer the egg.  She backs up a step and lets it roll towards me. I use my beak to immediately shift the egg onto my own feet. The transfer is a success!

After producing our egg, Penelope needs to replenish herself. She has lost 30% of her body weight, dropping from 70 pounds (32 kilograms) to 47 pounds (21 kilograms) and must head back to the sea to eat. Before she departs, we sing to each other to guarantee we will recognize each other’s voices when she returns. She departs with a small group of moms. They walk day and night to reach their destination.

For the next two months, while she is gone, I incubate our egg in my brood pouch, maintaining it at a solid 100° F (38° C).  During this time, I turn the egg in a slow, precise motion to prevent the chick from freezing. It’s delicate work in the high winds and dark conditions. To conserve my energy, I sleep, which is typically done standing up but, in this case, it also keeps the egg away from the ice. 

As winter hits us full force and the sun spends limited time in our sky, we males huddle to stay warm. In the dark, we gather in concentric circles, standing less than an inch (one millimeter) apart to maximize the toastiness. We continuously rotate from the cold exterior to the warm center where it is at least 75° F (24° C) so everyone has a chance to spend time in the warmth, protected from the harsh winds. Our lifesaving huddles last for an hour or two, break apart and then reform nearby.  

Pip, Pip, Hurray!

(Don’t) Put It on Ice (early August)

In early August, I hear a muffled chirp from my brood pouch. A tiny head peeks out and by jove, it’s a girl!  She peeps her request for sustenance, so I appease her with a curd-like substance I produce to feed her. My precious daughter weighs a scant seven ounces (200 grams) and has limited silver-gray and white down.

Within days, Penelope returns! As we see the ladies marching on the horizon, all the dads begin to sing, softly at first but it rises to a cacophony as the ladies near the colony. Penelope tunes out the other voices and quickly finds me and our new daughter, Genevieve. 

As soon as she arrives, Penelope feeds our little one her first meal of regurgitated fish then we transfer our daughter to Penelope’s feet. It has now been several months since I’ve eaten, and I have lost 26 pounds (twelve kilograms). I sing to Penelope and little Genevieve one last time to imprint my voice and then I’m off on my own journey back to the sea.

Strapping on the Feedbag

At Sea (August)

I return to the sea with a small, silent group of dads. We feed during the day for the next three weeks. We rest at night and also take several naps a day to save energy. Then it’s time to return to our families and feed our chicks.

And Baby Makes Three

Alternating Between the Ice and Sea (August through mid-December)

Once Penelope and I have both had a chance to replenish ourselves, we take turns nurturing Genevieve and feeding at sea. After each trip, we feed our daughter six and a half pounds (three kilograms) of partially digested fish. Initially, she can only take a little of that amount at a time. But as Genevieve grows, she accepts more and more in one sitting.  

Ultimately, both Penelope and I make seven trips to and from the sea and colony. Our trips get progressively shorter, with the final trip lasting less than a week. By this time, our daughter takes the entire offering in one shot. 

As December returns, Penelope and I must depart for the molting grounds to once again start our annual cycle. Genevieve does not need to make this journey and so, it is at this juncture that our little family goes in separate directions.

Fledging Allegiance to the Molt

Inaugural Trip to the Sea (December)

Hi there!  Genevieve here!  Papa said I could say hello and tell you about my first trip to the sea. By the time Mom and Dad are off to their molting grounds, I have mostly shed my fluffy down in favor of the sleek black and white tuxedo look. That’s a good thing because we chicks are quite vulnerable while we are downy and not at all waterproof.  With the sea ice sometimes breaking up prematurely, we may be forced into the water before we are ready, and we likely wouldn’t survive the experience.

With our juvenile plumage intact, we chicks follow in our parents’ proverbial footsteps and make our way to the sea as well. Once we arrive, we wander around the shore for hours, unsure of what to make of the water. And then, suddenly, one brave soul jumps in and we all follow suit. The sea is suddenly full of us awkward chicks, and we’re all flailing our wings at the surface and screaming loudly to protest this sudden immersion therapy. 

Despite the initial fuss, we quickly get the hang of how to maneuver through the water and as a group, we bid a fond farewell to the colony and swim away. Our journey takes us to the slightly warmer waters of the Southern Ocean several thousand miles (several thousand kilometers) away. And there, in three to five years, we mature into adults and join our parents in the grand annual emperor penguin adventure.