EMPEROR PENGUINS
Emperor penguin Emperor penguins (Scientific name: Aptenodytes forsteri) are the largest of all penguins — an average bird stands 115 centimeters (45 inches) tall and weighs up to 40 kilograms (88 pounds). "This is an animal that does things in extremes," said Paul Ponganis, a research physiologist at the Scripps Institute of Oceanography in San Diego. Ponganis has studied penguins for over a decade. "Emperors can fast for extreme amounts of time and dive to extreme depths, which allows them to live in a very extreme place." [Source: Jennifer Hile, National Geographic Channel, March 29, 2004]
Jennifer Hile of the National Geographic Channel said, “During the Antarctic winter the South Pole becomes the coldest place on the planet. Temperatures regularly plummet to -50ºCelsius (-60º Fahrenheit), prompting most of the 9,000 species of birds that cross the continent to hightail it for warmer climes. Only one bird — the emperor penguin — will winter on Antarctica and use the frozen continent as a nursery. When the winds really start howling, the birds march inland by the thousands, creating 40 or so breeding colonies on the sea ice along the edge of the continent.
Emperor penguins have a lifespan expectancy in the wild of 15 to 20 years, but some researchers suggest that one percent of individuals have lived to up to 50 years. Their lifespan in captivity is 20 to 34 years. Depending on environmental and climate factors, survival rates of chicks in their first year varies, with only 20 percent of chicks making it past the first year on average and hick mortality often exceeding 90 percent in their first year, with causes including starvation, predation, and harsh weather conditions. Annual survival rates for adult emperor penguins are around 95 percent. Annual average sea surface temperature is a factor that has been shown to influence adult survival. Emperor penguins survived less when surface temperatures were higher, roughly between -24°C and 10°C. [Source: Sarah Wilber, Animal Diversity Web (ADW) /=]
Emperor penguins are designated as “Near Threatened” on the International Union for Conservation of Nature (IUCN) Red List and have no special status according to the Convention on International Trade in Endangered Species (CITES). They are projected to undergo moderately rapid population decrease as Antarctic sea ice begins to disappear over the next few decades as a result of climate change. Currently, the population is considered stable, with about 476,000 individuals. Some research predicts thatby 2052, all emperor penguin colonies north of 67°S will disappeared due to lack of sea ice, caused by global warming. /=\
See Separate Articles: SEA BIRDS: TYPES, MIGRATIONS AND THREATS ioa.factsanddetails.com ; PENGUINS: CHARACTERISTICS, HISTORY AND SWIMMING ioa.factsanddetails.com ; ENDANGERED PENGUINS: DECLINING NUMBERS, THREATS ioa.factsanddetails.com ; PENGUIN BEHAVIOR, SEXUALITY AND YOUNG ioa.factsanddetails.com
Websites and Resources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Encyclopedia of Life eol.org; Smithsonian Oceans Portal ocean.si.edu/ocean-life-ecosystems ; MarineBio marinebio.org/oceans/creatures
Emperor Penguin Habitat and Where They Are Found
Emperor penguins live in polar, saltwater, marine habitats in, on and around icecaps and ice throughout coastal Antarctica and sub-Antarctic islands. They are typically found in coastal areas, around ice flows and in the open sea. . In breeding months (April to November), emperor penguin colonies are found between 66° and 78° south latitude, along the Antarctic coastline. One colony is located on the Antarctic peninsula, which is on the western base. Emperor penguins have been recorded on the Islas Malvinas, and are occasional visitors to Tierra de Fuego (South America’s southernmost tip) and Isla de Los Estados (18 kilometers east of Argentina). [Source: Sarah Wilber, Animal Diversity Web (ADW) /=]\
Winter temperatures in the Antarctic where the there range from -40º to 0º C (-40º to 32ºF) , with wind chills reaching -60°C (-76°C). During their breeding season, emperor penguins congregate on dense stable ice attached to the coastline of Antarctica. About seven to eight weeks after juveniles hatch, they leave their colonies and migrate toward open ocean areas. Outside of breeding season, they spend most of their time in seasonally-packed ice zones, where open sea is easily available for foraging. Colonies migrate to ice shelves during breeding season, where ice cliffs and icebergs serve as protection against cross winds.
How do emperor penguins live on the Antarctic ice and in the frigid surrounding waters? They employ physiological adaptations and cooperative behaviors in order to deal with an incredibly harsh environment. In the winter they huddle together to escape wind and conserve warmth. Individuals take turns moving to the group's protected and relatively toasty interior. Once a penguin has warmed a bit it will move to the perimeter of the group so that others can enjoy protection from the icy elements.
Emperor Penguin Physical Characteristics
Emperor penguins Emperor penguins are the largest sea birds in the Antarctic and one of the heaviest birds period. They range in weight from 25 to 45 kilograms (55 to 99 pounds) and range in length from one to 1.32 meters (3.3 to 4.3 feet). Their wingspan ranges from 76 to 89 centimeters (2.5 to 3 feet). Males are larger than females. They are endothermic (use their metabolism to generate heat and regulate body temperature independent of the temperatures around them). [Source: Sarah Wilber, Animal Diversity Web (ADW) /=]
Emperor penguins have black and white bodies with stiff black wings. According to Animal Diversity Web: Their back, head, chin, throat, and the dorsal parts of their wings are black. Their undersides, or ventral sides, are completely white up to their necks. They have auricular (ear-region) patches of orange and yellow that fade towards their shoulders. This yellow fades to white around the top portion of their chest. They also have patches of orange and yellow on their heads and breasts. Emperor penguins have beaks that are long and black, with pinkish-orange stripes along their lower mandibles. Emperor penguins weigh 25 to 45 kilograms as adults. They gain and lose weight rapidly during breeding and feeding seasons. On average, females tend to weigh 18 kilograms less than males. /=\
When they are born, emperor penguins have gray skin with no feathers and weigh around 315 grams. Gray feathers fill in after the first couple of weeks of birth, after which a black crown of feathers going from their bill to the back and sides of their head develops. Around the same time, white cheeks and a white chin appear. As juveniles, emperor penguins are grayish-blue, aging as developing their distinct black-and-white patterns as they mature./=\
Emperor Penguin's Amazing Leaping Abilities
Emperor penguins are famous for their ability to dramatically leap out of the water. To do this they may preen at the surface to fill their plumage with air. Then they dive, at about two meters (6.5 feet) per second, and make sure there are no obstructions and build up speed. For the final surge, air is released from their feathers, coating the penguin’s body with a thin layer of tiny bubbles that reduces drag caused by friction. They often follow the air path of other penguins and reach speeds of 5.5 meters (18 feet) per second. [Source: Glenn Hodges, National Geographic, November 2012]
According to National Geographic. After hunting at sea to get food for their chicks, adult emperor penguins swim at the surface, which loads their plumage with air. Then they’ll dive deep, gather speed, and race toward their exit hole. Sometimes they mill around in the depths as they prepare for their swift ascent to the sea ice.“Once they start to launch,” photographer Paul Nicklen says, “within 30 seconds they’re all standing on the ice.”
Emperor penguins reach maximum speed right before they launch from the sea to the sea ice. An airborne penguin shows why it has a need for speed: To get out of the water, it may have to clear more than a meter (several feet) of ice. A fast exit also helps it elude leopard seals, which often lurk at the ice edge. When it leaps from the water, it will land with a thump and a squeak and leave its most graceful moves behind. Nicklen positioned himself at their exit hole to get a shot:: “I was about three feet away...They were sending up so much spray and ice. The noises and thuds when they landed on the ice were incredible. They knocked the air out of themselves and made a squeak.”
Roger Hughes, a marine biologist at Bangor University in north Wales, John Davenport, a marine biologist at University College Cork in Ireland and Poul Larsen, a mechanical engineer at the Technical University of Denmark, analyzed hours of underwater footage of emperor penguins and discovered that the penguins were able ro something that engineers had long tried to do with boats and torpedoes: They were using air as a lubricant to cut drag and increase speed.
Emperor Penguin Diving and Underwater Flight
Emperor penguins have been recorded diving to a depth of 525 meters (1,720 feet) and staying submerged for 22 minutes. A critter was hooked up to one in 1999 by National Geographic researchers Jennifer Hile of the National Geographic Channel said, “Emperor penguins are veritable sea bullets — they can zoom to a depth of 1,500 feet (500 meters) to feed...That allows the penguins to exploit resources other birds can't. Working from his gale-proof base at the McMurdo Station on Ross Island, just off the Antarctic continent, Ponganis tags along on some of the penguins' dives by corralling a few of them and attaching miniature video recorders to their backs. Other bite-sized gadgets measure the penguin's oxygen levels, heartbeat, and temperature. [Source: Jennifer Hile, National Geographic Channel, March 29, 2004]
"Penguins are as well designed for underwater flight as birds are for flying in the air," Ponganis said. "And when they swim, they really are flying underwater. A penguin's wings act the same while it's swimming as a bird's does while it's flying."
However, a penguin's strokes are even more efficient. "Emperors can exert propulsion on both the upstroke and downstroke, while most other birds only exert pressure on the downstroke [during flight]," said Ainley, Long glides to the surface probably help emperor penguins conserve energy during their deepest dives. Another key is their solid bones. While skybound birds have evolved hollow bones to lighten their weight, penguins gradually lost that internal airspace — decreasing their buoyancy so they can plumb the depths. Even then, emperor penguins never get wet.
Emperor Penguin Feathers and Speed
Emperor penguins’ dense-feathers occupy the bird’s body at a density of about 40 per square centimeter. They overlap like roof tiles and seal out water and trap air in the downy underlayer. The base of each shaft is made up of microscopic filaments that hold the layer of air near the body. Muscles attached to the flexible membrane allow the penguins to change the position of their feathers allowing air in and out. When the air is released it is in the form of lubricating bubbles. [Source: Glenn Hodges, National Geographic, November 2012]
An emperor penguin’s outer feathers are flat, well oiled, and watertight. There is an air space between those feathers and the bird's skin that water never penetrates, keeping them from turning into icicles in the black Antarctic sea. "They have the highest feather density of any bird, about a hundred feathers per square inch (6.5 square centimeters)," said David Ainley, an ecologist at H.T. Harvey and Associates, a biological consulting firm in San Jose, California. Ainley has studied Antarctic birds for over 20 years. "Underneath their feathers, it can be 30º to 35º Celsius [86º to 95º Fahrenheit], while the outside air is -20º or - 30º Celsius [-48º or minus 22º Fahrenheit]," Ponganis said. "That's more than a 60º temperature difference separated by a layer of feathers that is maybe a half an inch (one centimeter) thick."
Glenn Hodges wrote in National Geographic: When an emperor penguin swims through the water, it is slowed by the friction between its body and the water, keeping its maximum speed somewhere between four and nine feet a second. But in short bursts the penguin can double or even triple its speed by releasing air from its feathers in the form of tiny bubbles. These reduce the density and viscosity of the water around the penguin’s body, cutting drag and enabling the bird to reach speeds that would otherwise be impossible. (As an added benefit, the extra speed helps the penguins avoid predators such as leopard seals.) [Source: Glenn Hodges, National Geographic, November 2012]
The key to this talent is in the penguin’s feathers. Like other birds, emperors have the capacity to fluff their feathers and insulate their bodies with a layer of air. But whereas most birds have rows of feathers with bare skin between them, emperor penguins have a dense, uniform coat of feathers. And because the bases of their feathers include tiny filaments — just 20 microns in diameter, less than half the width of a thin human hair — air is trapped in a fine, downy mesh and released as microbubbles so tiny that they form a lubricating coat on the feather surface.
Emperor Penguin Behavior and Communication
Emperor penguins are motile (move around as opposed to being stationary), nomadic (move from place to place, generally within a well-defined range) and colonial (living together in groups or in close proximity to each other). They don’t seem to have a home range and they don’t defend a territory. [Source: Sarah Wilber, Animal Diversity Web (ADW) /=]
According to Animal Diversity Web: Emperor penguins display common behaviors characteristic of many seabird species, however there are behaviors unique to this species. During breeding and incubation periods in harsh Antarctic weather conditions, groups of penguins huddle as a way to conserve energy. Huddles may be small — less than 200 birds — or as large as 5,000 or 6,000 birds. The average duration of huddles averages 1.6 hours. Penguins in huddles make small, continuous movements, alternately getting closer to each other and breaking apart. This preserves energy and allows these penguins to fast for long periods of time. Ancel et al. (2009) report that 84 percent of mate pairs stay together during huddling events. Exactly how partners stayed together is not known. Chicks in groups, known as a crèche, also huddle to stay warm and conserve energy. /=\
Emperor penguins also lie down, which helps lower metabolic rate and conserve energy in harsh Antarctic conditions. This individual behavior decreases the amount of body surface area exposed to cold air, minimizing heat loss due to high-speed winds. Ground-level snow also acts like a wind barrier. During incubation periods, males remain nearly motionless for days at a time to decrease their metabolic rates. Their stance has adapted in such way to minimize heat loss. They stand on three resting points: their two heels, and tail. The plantar surfaces of their feet do not touch the ground, minimizing heat loss to the ground. The rest of their body is situated in such way to prevent freezing. They tuck their heads to their chests and press their flippers tightly against their bodies. In breeding season, mating pairs use vocal songs as a demonstration of their partnership. Penguins use these vocal songs to locate their mates when they return from the ocean during breeding season. Chicks also use calls to locate their parents.
Emperor penguins communicate with vision, sound and mimicry and sense using vision, sound, touch, ultrasound and chemicals usually detected with smelling or smelling-like senses. /=\ Emperor penguins are relatively vocal birds that use different frequencies for mate pairing, mate recognition, and offspring/parent recognition. Most vocal communication is transmitted through a pair of different frequencies. Display calls are directed towards specific individuals, for example in-between mates. Mates rely on these specialized vocal calls during the breeding seasons to locate each other, because they spend the majority of their time apart. Parents and offspring also use calls to identify each other. Chicks also use high frequency whistles to tell their parents when they are hungry. In order for chicks to be fed, they must recognize and respond to their parents calls. Non-verbal movements are also used for communication. Parents teach their offspring how to swim and feed. Emperor penguins also a non-verbal posture to communicate between other individuals. They frequently stand in an obvious posture with their bills turned up and wings slightly out in order to avoid aggression./=\
Emperor Penguin Feeding and Predators
Emperor penguins are carnivorous and primarily feed on fish, crustaceans, and molluscs. They feed on fish and krill the most, as they are most abundant in the ocean surrounding Antarctica. Emperor penguins have a rough and spiky-textured tongue, which helps them catch and eat slippery fish and squids more easily. Prey abundance varies from location to location, but some research has found that the Antarctic silverfish is one of the most frequently consumed species. Cod-like fish are also staples of their diet. Glacial squid, hooked squid and Antarctic krill are also eaten regularly. They feed in the open waters of the ocean surrounding Antarctica, or underneath sea ice. They can dive to depths of up to 500 meters. When hunting, they dive below their prey so they can look up and see the fish in silhouette against the sea ice and then zoom in for the kill. [Source: Sarah Wilber, Animal Diversity Web (ADW) /=]
Emperor penguins may travel up to 1000 kilometers in one offshore feeding period. According to Animal Diversity Web: Staying in the sea for unnecessary lengths of time increases their chance to be attacked by prey, so they tend to stay closer to the surface as long as food is plentiful. They can travel up to 20 kilometers per hour in the water, however they generally travel around 10 kilometers per hour. /=\
Some observations suggest that groups of penguins coordinate their dives and hunt cooperatively. An adult penguin eats two to three kilograms per day. However, before the long fasting breeding season, they tend to eat up to six kilograms per day. Chicks rely solely on their parents for food for the first five months of their lives, and typically require an average of 84 kilograms of food during those months. /=\
Emperor Penguins and Predators
Emperor penguins are one of the top predators in the Antarctic marine environment. Killer whales have been observed preying on emperor penguins and harassing them for fun. Leopard seals are also marine predators who feed on penguins but research indicated that emperor penguins are not a part of their usually diet. Because of their large size, emperor penguins may not be the primary prey of killer whales and leopard seals, who prefer smaller penguins. [Source: Sarah Wilber, Animal Diversity Web (ADW) /=]
Some scientists have observed adult and young emperor penguins being heavily preyed upon by leopard seals. This may have been because few other food sources were available. Seabirds called skuas steal and eat emperor penguin eggs and chicks. Little is known about how penguins protect themselves from predators. Most emperor dives are shallow and fairly quick, which makes it harder for predators to reach them before they are out of the water again. In addition to a large pointed beak, their feathers and shape of their body also likely function as protection from predators. With black backs and white bellies, emperor penguins are countershaded. This makes it harder to distinguish their form while they are swimming. /=\
Life is safer in a colony or a group, where predators are few and if one is near by the chances are it will get somebody else. The danger of ambush by leopard seals is greatest when entering the water, so penguins sometimes linger at the edge of an ice hole for hours, waiting for one bold bird to plunge in. Without the safety of numbers, a lone penguin corkscrews around get a 360-degree view of its surroundings. Emperors can bolt away for any number of reasons, as photographer Paul Nicklen discovered when he spooked this group. “A tenth of a second after I took this picture, all I could see were bubbles.” [Source: Glenn Hodges, National Geographic, November 2012]
Emperor Penguin Mating and Reproduction
Emperor penguins only have sex once a year for a period of two or three minutes. During copulation the female lies face down on the ice, supporting herself with her beak and flippers. The males mounts her, holding her beak with his beak, and balances himself with his flippers. The process is difficult and the male often slips and falls in the water before he is successful.
Emperor penguins breed once a year from April to December. Their breeding cycles are in sync with Antarctic sea-ice cycles. From January to March, adults store energy in fat for the upcoming breeding season, where they fast for a period of months. Penguins arrive at breeding grounds on sea-ice in early-mid April at the onset of the Antarctic winter. The average number of eggs per season is one. The average time to hatching is 65 days. The average fledging age and the average time to independence is five months.Females and males reach sexual maturity at four to six years. [Source: Sarah Wilber, Animal Diversity Web (ADW) /=]
Emperor penguins are monogamous (have one mate at a time). A long courtship period begins, lasting up to six weeks, and encompasses about 16 percent of the total breeding cycle. Mate pairing usually occurs in 82 percent of males and 56 percent of females within 24 hours of arrival to breeding grounds. Males and females use vocal calls to find mates. After they bond with a partner, emperor penguins no longer vocalize. This prevents disturbances by other individuals seeking mates. Vocal communication returns once females lay their eggs. Individual females lay one egg per mating season. /=\
Emperor Penguin Parental Care of Young
Parental care is provided by both females and males. Pre-birth provisioning and protecting are provided by the male. During the pre-weaning and pre-independence stages provisioning and protecting are done by females and males. Females lay a single egg in late April or May and pass the egg off to their mate almost immediately. Females then travel approximately 50 to 120 kilometers back to the ocean to find food. Eggs weigh around 450 grams — just two percent of the body mass of an adult female. Because they incubate eggs for a long period with no food, males lose roughly 40 percent of their total body mass. [Source: Sarah Wilber, Animal Diversity Web (ADW) /=]
According to Animal Diversity Web: Chicks hatch in mid-July, weighing about 315 grams. Because of the harsh conditions, males keep eggs in special brood pouches. Males feed hatchlings by producing a nutrient-rich, milky substance in their esophagus until females return. Depending on how far mothers have to travel for food, their return may be before the chicks hatch or up to a month thereafter. Females locate their mates upon return via vocal searches. Once females return, they take over caring for young. After roughly 4 months of fasting, males return to the ocean to eat. Females feed their young by regurgitating food from their stomachs. Chicks stay inside adult brood pouches until they are about a month old. At this age, they start to become independent and increasingly spend more time outside of brood pouches. Maho (1977) reported chick mortality rates of over 90 percent, with causes including starvation, predators, and harsh weather conditions. By the time chicks are five months old they are completely independent from their parents. Chicks molt at this age and are approximately 50 percent the size of a full grown adult. Molting is vital for any chance of survival. Chicks leave their parents and go off on their own with other chicks. Parents also molt and return to sea to start storing up energy for the next breeding season. Emperor penguins have a low mate fidelity rate. Bried et al. (1999) reported that only 15 percent of mates stayed together for multiple years, with a maximum time of 4 years. /=\
Emperor penguins rely on their parents until independence — around five months of age. Males incubate and protect eggs in their brood pouches, a specialized skin fold on their lower abdomens. They do this for roughly 65 days, or until females have returned. When chicks are born, they live solely underneath the brood pouches of the males. They are fed a nutrient-rich, milky substance that is secreted in the esophagus. When the females return, they take over caring and feeding their offspring by regurgitating food from their stomachs. Both males and females take turns going to and from the ocean to forage, bringing their offspring food until they are five months old. At this point, chicks leave their parents and molt their juvenile feathers in preparation to start diving for their own food. /=\
Male Emperor Penguins Care for Eggs in the Harsh Cold
Jennifer Hile of the National Geographic Channel said, “Emperor penguins spend the long winter on the open ice — and even breed during this harsh season. Females lay a single egg and then promptly leave it behind. They undertake an extended hunting trip that lasts some two months! Depending on the extent of the ice pack, females may need to travel some 50 miles (80 kilometers) just to reach the open ocean, where they will feed on fish, squid, and krill. At sea, emperor penguins can dive to 1,850 feet (565 meters) — deeper than any other bird — and stay under for more than 20 minutes. [Source: Jennifer Hile, National Geographic Channel, March 29, 2004]
Male emperors keep the newly laid eggs warm, but they do not sit on them, as many other birds do. Males stand and protect their eggs from the elements by balancing them on their feet and covering them with feathered skin known as a brood pouch. During this two-month bout of babysitting the males eat nothing and are at the mercy of the Antarctic elements.
Not only do emperor penguins rear their young in the extreme Antarctic environment — they do it while fasting. Once they hit the ice, there will be no opportunity to feed. After the female lays her egg and passes it off to the male, allowing her to head for the sea to feed. The male promptly tucks the egg into a small pouch over his feet. He will balance it there until it hatches. Inside the pouch, the egg is kept at a toasty 95 degrees Fahrenheit (35 degrees Celsius) the average body temperature of an adult.
The key to surviving this impossible feat is the huddle. Rarely moving, never eating, standing in frigid cold, the fathers-to-be will lose half their body weight incubating their egg over the next two months. Most male penguins are known for being obstreperous, territorial squawkers. Not emperor penguins. They huddle in tight knit groups that can number in the thousands while tending their eggs.The largest colony is on Coulman Island in the Ross Sea, where as many as 25,000 males hunker down.
Huddling keeps them warm. There can be a 20̊ to 30̊ temperature difference between ambient air inside the huddle compared to the shrieking cold outside it. Since the animals don't have to work as hard to stay warm, their metabolism slows down and they burn less fat. As a result, their ability to survive the fast increases.
Emperor Penguins Care for Their Young in the Harsh Cold
When they have the opportunity, emperor parents and chicks bask in the brief summer sun. The distance to open water varies with the season; in midwinter birds may have to cross kilometers of ice to feed. Jennifer Hile of the National Geographic Channel said, “When female penguins return to the breeding site, they bring a belly full of food that they regurgitate for the newly hatched chicks. Meanwhile, their duty done, male emperors take to the sea in search of food for themselves. [Source: Jennifer Hile, National Geographic Channel, March 29, 2004]
Mothers care for their young chicks and protect them with the warmth of their own brood pouches. Outside of this warm cocoon, a chick could die in just a few minutes. In December, Antarctic summer, the pack ice begins to break up and open water appears near the breeding site, just as young emperor penguins are ready to swim and fish on their own.
Although scientists like Ponganis and Ainley have discovered much about how the birds thrive in this harsh climate, that doesn't answer the question of why they choose to raise their young during the raging Antarctic winter. "The reason that they do it is for the stability of sea ice. They are breeding and rearing their young on ice that will melt come summer," Ponganis said. "Starting in January, their colony sites will begin breaking up into open ocean." Once the chick is born around early August, the mother returns from feeding at sea to give dad a break. For the next five months, he and his partner will take turns regurgitating fish and squid to the chick.
Once the sun starts heating up the water and the ice begins to dissipate, the emperors leave their chicks, forcing them to fend for themselves for the first time. "December is the start of the Antarctic summer, when food is most available, thus making it as easy as possible for their chicks to forage," Ainley said. As the ocean swells start tearing apart the ice, the young chicks become increasingly agitated. Once it's clear their parents are not returning, usually in the first week of January, the chicks head from a world of collapsing white into a dark and frigid sea. For their parents, a few months of gorging begins in preparation for the following May, when the ritual of rearing young in the most forbidding climate on Earth begins anew.
Emperor Penguins Count by Satellite Finds Twice as Many as Expected
In 2012, scientists announced that the population of emperor penguins in Antarctica was nearly twice as large as previously according to estimates made using a satellite-based census technique based on detecting penguin colonies — by looking for large patches of ice discolored by penguin poop — then counting individual birds. The technique revealed 44 colonies across Antarctica — including seven that hadn’t been detected previously — and 595,000 birds. The emperor population had previously been thought to range between 170,000-350,000 birds. [Source: Mongabay.com, April 14, 2012]
“The methods we used are an enormous step forward in Antarctic ecology because we can conduct research safely and efficiently with little environmental impact, and determine estimates of an entire penguin population, said co-author Michelle LaRue from the University of Minnesota in a statement. “The implications of this study are far-reaching: we now have a cost-effective way to apply our methods to other poorly-understood species in the Antarctic, to strengthen on-going field research, and to provide accurate information for international conservation efforts.”
According to Mongabay: The findings are significant because they help scientists determine a baseline from which they can measure the impact of climate change on emperor penguin populations. Ecologists say many penguins may be vulnerable to shifts in prey distribution and density as well as changes in sea ice cover, which could increase mortality rates of fledgling penguins. “Current research suggests that emperor penguin colonies will be seriously affected by climate change,” said co-author Phil Trathan of the British Antarctic Survey. “An accurate continent-wide census that can be easily repeated on a regular basis will help us monitor more accurately the impacts of future change on this iconic species.” The research is published in an April 2012 issue of PLoS ONE: “An Emperor Penguin Population Estimate: The First Global, Synoptic Survey of a Species from Space”.
Image Sources: Wikimedia Commons, NOAA
Text Sources: Animal Diversity Web (ADW) animaldiversity.org; National Oceanic and Atmospheric Administration (NOAA) noaa.gov; Wikipedia, National Geographic, Live Science, BBC, Smithsonian, New York Times, Washington Post, Los Angeles Times, The New Yorker, Reuters, Associated Press, Lonely Planet Guides and various books and other publications.
Last Updated May 2023