On the Ice Edge

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Many male penguins gift female penguins with rocks in order to woo them

On the

Ice Edge

Penguins & their Species Nº1/ 22 Janeiro 2021

Who is the penguins only live in antarctca? smallest peguin?

Habitats and distribution

curiosities about penguins



Welcome to

On the

Ice Edge In the past, when talking about the ice lands, I thought of a cold, boring and lonely place, but that’s when I was wrong, in these lands many different and fascinating animals live. At Ice Edge it aims to show how interesting the ice lands can be. And in the pages that follow we will explore one of the species of these lands, the penguins, and we will also talk a little about these lands.


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Penguins & their species

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Curisities about penguins


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Pe n g u i n s

Penguins are flightless seabirds that live almost exclusively below the equator. Some island-dwellers can be found in warmer climates, but most—including emperor, adélie, chinstrap, and gentoo penguins— reside in and around icy Antarctica. A thick layer of blubber and tightly-packed, oily feathers are ideal for colder temperatures. The 18 different species of penguins can widely in shape and size but all have black bodies and white bellies. This protective countershading allows them to hide from predators like leopard seals and orcas while they swim. While penguins can’t fly, their stiff flippers, webbed feet, and sleek shape make them expert swimmers. In fact, they spend most of their lives in the ocean and do nearly all of their hunting for krill, squid, and crabs underwater. They can swim about 15 miles an hour, and when they want to go faster, they often porpoise, or leap out of the water as they swim.


Breeding

Penguins

Penguins come ashore to lay their eggs and raise their chicks. Most penguins stay with their mate for many years and lay only one or two eggs at a time. Parents take turns keeping their eggs warm, and when they hatch, feeding and protecting the chicks. For a few weeks each year, thousands of baby birds wait together while their parents forage for food. When mother and father return, chicks listen for the unique audio frequency of their parents’ call, allowing them to reunite in a large, noisy crowd. Soon after the chicks fledge, parents will begin molting. Unlike some birds that shed a few feathers at a time, penguins lose all their feathers at once during a process called catastrophic molt. They condense this process to just a few weeks because they must fast during this time— they can’t hunt without their waterproof feathers.

Life on land

On land, penguins have an upright stance and tend to waddle, hop, or run with their bodies angled forward. Polar penguins can travel long distances quickly by “tobogganing,” or sliding across the ice on their bellies and pushing forward with their feet. If it’s especially cold, they huddle together in large colonies that protect them from predators and provide warmth. These colonies consist of thousands, and even millions, of penguins.

Conservation and threats

About two-thirds of penguin species are listed as threatened on the IUCN Red List, making them one of the most endangered seabirds. Loss of habitat, disease, and infectious diseases spread by tourists loom as threats. Commercial fishing in the Southern Ocean is also a significant concern, as it has reduced fish supply by about half in the Antarctic Peninsula. This forces many penguins to compete for food, and puts them in danger of getting accidentally captured by fishing nets. Among the biggest threats to penguin populations is climate change. Warming in the polar regions has melted sea ice, which penguins depend on to find food and build nests. Rapidly changing conditions mean Antarctica could lose most of its penguins to climate change by the end of the century. To survive, they may have to relocate to new habitats.


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Penguins & Their Species King Penguin

Galapagos Penguin

Emperor Penguin

Magellanic Penguin

Southern Rockhopper Penguin

African Penguin

Northern Rockhopper Penguin

Humboldt Penguin

Adelie Penguin

Snares Penguin

Gentoo Penguin

Fiordland Penguin

Royal Penguin

Blue Penguin

Macaroni Penguin

Yellow-eyed Penguin

Chinstrap Penguin

Erect-crested Penguin

Here’s a list of Penguin species. In total there are 18 species in the penguin family, of which 11 are Globally Threatened according to BirdLife on behalf of the IUCN Red List. The list of penguins includes aquatic, flightless birds living almost exclusively in the southern hemisphere, especially in Antarctica. Highly adapted for life in the water, members of the penguin familiy have countershaded dark and white plumage, and their wings have become flippers.


Penguins

King Penguin King penguin, second largest member of the penguin order, characterized by its dignified, upright posture, long bill, and vivid coloration. Emperor penguins spend all year in Antarctica, while king penguins live in sub-antarctic island groups and in southern South America. The king penguin is the largest penguin outside of Antarctica. King penguins are foraging predators that feed primarily on fishes (but occasionally take squids) in shallow water near their nesting sites. Many predatory seabirds are known to take juvenile king penguins, while leopard seals, killer whales, and other large predators are the only species that typically eat adults. With apparently increasing populations, the king penguin has been determined to be a species that is not at risk of extinction. It is not dependent on ice for nesting (like Antarctic penguins) and it generally does not live in places with significant local human impacts (like South American or African penguins). And it does not rely on krill and other prey that are vulnerable to overfishing and climate change (like many other Southern Ocean predators). However, it is important to continue to study king penguins and monitor their populations to ensure that any future negative trends are discovered early and are handled accordingly.

photo of a KIng penguin baby


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Emperor penguin

Emperors are the largest of all penguins—an average bird stands some 45 inches tall. These flightless animals live on the Antarctic ice and in the frigid surrounding waters.

Antarctic Adaptations

Penguins employ physiological adaptations and cooperative behaviors in order to deal with an incredibly harsh environment, where wind chills can reach -76°F. 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 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 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—deeper than any other bird—and stay under for more than 20 minutes.

Conservation Status The emperor penguin is considered a near threatened species by the International Union for Conservation of Nature (IUCN). Ecologists have recorded population declines in some emperor penguin colonies. The largest population decline (50 percent) was observed between 1950 and 2000 in a colony located in the Terre Adélie region in East Antarctica. With the breakup of large areas of sea ice, such as the loss of 60 percent of the Larsen Ice Shelf between 1995 and 2002, emperor penguin habitat has declined, resulting in the production of fewer young and higher rates of chick mortality. Despite the discovery of additional colonies, which lifted the estimated number of breeding pairs to more than 275,000, scientific models predict drastic population decreases in emperor penguin colonies along the Antarctic Peninsula as sea ice coverage continues to fall.


Penguins

Rockhopper penguins Rockhopper penguins are small-bodied penguins, reaching heights of about two feet (0.6 m) and weights of only a few pounds. Rockhopper penguins have white fronts and black heads and hoods. Their beaks are bright orange, and their eyebrows are bright yellow. At the outer edge of the eyebrows, long yellow feathers extend off the sides of the head. They were once part of a single species, which was separated into two subspecies-a northern group and a southern group.

Population Decline

Behavior

These penguins are among the most numerous on the planet, but their population is at-risk. Colonies on the Falkland Islands were once the largest anywhere, but commercial overfishing, pollution, and other factors have cut the penguins numbers dramatically. Breeding colonies on other islands are in trouble as well, and some estimates say rockhopper penguins have declined by more than 30 percent over the last 30 years of the 20th century.

Habitat Biologists left little ambiguity about this species’ preferred habitat when assigning its name. Rockhoppers are found bounding—rather than waddling, as most other penguins do—among the craggy, windswept shorelines of the islands north of Antarctica, from Chile to New Zealand.

During annual breeding times, rockhoppers gather in vast, noisy colonies, often numbering in the hundreds of thousands, to construct burrows in the tall tussock grasses near shore. They return to the same breeding ground, and often to the same nest, each year, and usually seek out their previous year’s mate. Both parents take turns incubating the eggs, aggressively pecking at anything, big or small, that may stray too close. Rockhoppers ply the frigid waters of their range using strong, narrow, flipper-like wings for propulsion. They usually stick to the shallows, but are capable of diving up to 330 feet in pursuit of fish, crustaceans, squid, and krill.


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Adélie penguin Adélie penguin (Pygoscelis adeliae), is a specie of penguin characterized by black and white plumage and a small ring of white feathers surrounding each eye. During the warmer months Adélie penguins are found primarily in several breeding colonies along rocky, ice-free coasts of Antarctica; colonies also occur on the South Shetland, South Orkney, and South Sandwich Islands. During the winter months they migrate northward to forage in areas of open water in the pack ice.

Predators and Prey Although Adélie penguins are capable of descending to approximately 170 metres beneath the surface of the ocean in search of prey, they prefer to hunt within the first 50 metres where light availability is greatest. They subsist on krill. They also feed on Antarctic blennies and cephalopods. Killer whales and leopard seals prey upon adult and juvenile Adélie penguins at sea; leopard seals also attack and kill Adélie penguins from beneath thin ice. Chicks may be taken by skuas and giant fulmars.

Behavior One interesting behavior of the Adélie penguin is its reluctance to be the first individual that enters the water. This species is known to form dense groups at the water’s edge waiting for an individual to either fall or be pushed into the water. Only after that first individual is seen safely swimming away to feed do the others in the group follow. This behavior is thought to be used to avoid predation by leopard seals, killer whales, and other large animals. Adélie penguins have no natural land predators and are extremely curious about people. They often walk right up to researchers as if conducting their own studies.


Penguins

Gentoo penguin Gentoo penguin, is a specie characterized by a band of white feathers extending across the top of the head from just above each eye. Other distinguishing features include a black throat, a brush tail that is large in comparison with other penguin species, and a bill that is mostly deep orange or red.

Gentoo penguins are native to sub-Antarctic islands where chilly temperatures allow for ideal breeding, foraging and nesting conditions. Despite living in cold climates, gentoo penguins typically live in ice-free areas like flat, rocky beaches and low-lying cliffs where large colonies of individuals can gather. Like other penguin species, gentoo penguins rely on the ocean for food and are never far from the water.

population declines Gentoo penguins are a favored menu item of the leopard seals, sea lions, and orcas that patrol the waters around their colonies. On land, adults have no natural predators other than humans, who harvest them for their oil and skin. Gentoo eggs and chicks, however, are vulnerable to birds of prey, like skuas and caracaras. Gentoo numbers are increasing on the Antarctic Peninsula but have plummeted in some of their island enclaves, possibly due to local pollution or disrupted fisheries. They are protected by the Antarctic Treaty of 1959 and received near threatened status on the IUCN Red List in 2007.

These penguins take advantage of stream-lined bodies and strong “flippers” in the water to dive more than 600 feet deep and swim up to 22 miles an hour, the fastest of any other diving bird. Gentoo penguins primarily feed on crustaceans, fish and squid. Adult gentoo penguins are relatively small, weighing about 12 pounds and standing 30 inches tall on average.


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Royal penguins Royal penguins’ nest in large Fitted with black crowns and colonies on Macquarie Island short orange bills, these penand nearby Bishop and Clerk guins are also the tallest of cresIslands in Australia. They favor ted penguins, standing at about rocky or pebbly beaches du28 inches tall. Females are often ring most of the year. They are slightly smaller than the males. members of the crested pen- Royal penguins feed primarily guin family, but unlike other on krill, along with other small crested penguins that have bla- crustaceans, fish or cephalock chins, royal penguins’ chins pods, and may fall prey to fur and faces are pale grey or white seals or southern elephant seals. leading up to their colorful plumes.

Conservation Status Royal penguins were heavily exploited in the 19th century but have since recovered. Today, populations are considered stable, but since potential threats like plastic pollution and overfishing are prevalent in their habitat, royal penguins are listed as Near Threatened by the IUCN Red List. Long-term effects of climate change may also severely impact these penguins’ food supply throughout their range.

Macaroni penguin Macaroni penguin, species characterized by a large reddish orange bill, a black face and chin, and a long crest of yellow-orange feathers that contrast with the black feathers on the head. The species is found on the Antarctic Peninsula, on a number of Antarctic and subantarctic islands in the Atlantic and Indian oceans, and on the islands near the coasts of Chile and Argentina. Macaroni penguins are often confused with royal penguins, and some ornithologists argue that both groups should be classified as a single species. The common name of the species is taken from macaroni fashion, the name for the exaggerated style of dress that appeared in Europe during the late 18th century.


Penguins

Chinstrap penguin The largest colony, on the Chinstrap penguin, also called ringed penguin or bearded penguin, uninhabited South Sandwich island of Zavodovski, hosts some is characterized by a cap of black plumage on the top of the head, a 1.2 million breeding pairs. Baily white face, and a fine, continuous Head in the South Shetland band of black feathers that extends islands is home to more than 100,000 pairs. from one side of the head to the other across each cheek and under Chinstrap penguins are the most the chin. The common name of the abundant penguin in the species derives from the presence Antarctic, where they gather in of this “chinstrap” of black feathers. massive breeding colonies. After spending the winter north Other distinguishing features of the sea ice, chinstraps return in include a fine ring of black skin late October or early November around each eye and a black bill. to their nest sites, usually with the The sheer number of birds in the same breeding partners. colonies is astounding.

These colonies are on the rocky, ice-free coasts of the South Sandwich Islands, South Shetland Islands, and Antarctic continent. The sheer number of birds in the colonies is astounding. The largest colony, on the uninhabited South Sandwich island of Zavodovski, hosts some 1.2 million breeding pairs. Baily Head in the South Shetland Islands is home to more than 100,000 pairs.


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Galápagos penguin As the only penguin species to be found north of the equator, the Galápagos penguin is a special bird. The smallest of the penguin species they make their homes in caves and crevices all along the coastlines. These little black and white birds are super-agile swimmers and spend much of their time hunting. The key to penguin survival at the Galápagos Archipelago is keeping cool which is in turn dependent on the environmental conditions. Penguins rely on the chilly, sardine-rich waters of the Humboldt current in which to hunt and relate their temperature However, during an El Niño event, the penguins cannot get enough to eat and this can greatly limit their breeding success. For example, the 1982 El Niño event caused a 77 percent reduction in Galápagos penguin population due to

starvation. It’s thought that there are currently around just 800 breeding pairs left in the wild. Another reason for the limited breeding success of these penguins is a shortage of space for building nests - many historical nesting sites are periodically flooded, or used by marine iguanas. To combat this, conservation efforts have been put in effect to provide the Galápagos penguins with artificial netting sites. These have provided a safe place for penguins to raise young. They’re preyed on naturally by sharks fur seals and sea lions, but are also threatened by non-native invasive species such as cats and dogs. As marine species, they’re also threatened by pollution (especially by plastics), climate change and bycatch -all crucial issues facing modern marine conservation.


Penguins

Magellanic penguin Magellanic penguin, species of penguin characterized by the presence of a broad crescent of white feathers that extends from just above each eye to the chin, a horseshoe-shaped band of black feathers that cuts across the white feathers on the chest and abdomen, and a small but noticeable region of pink flesh on the face. Adults are sometimes mistaken for African penguins, which display a small fleshy region over each eye, or Humboldt penguins, whose fleshy region encompasses the base of the beak and both eyes. The geographic range of the Magellanic penguin is limited to the Falkland Islands and several nearshore islands along the Pacific and Atlantic coasts of southern South America; however, some individuals have travelled as far as Peru, Brazil, Australia, New Zealand, and the Antarctic Peninsula. Magellanic penguins are named for Portuguese explorer Ferdinand Magellan; however, Italian explorer Antonio Pigafetta, who traveled with Magellan during his attempt to circumnavigate the globe in 1520, is credited with sighting the species.

Conservation treats

Physical Features In terms of body size, on average, Magellanic penguins are the largest members of the genus Spheniscus—a group that also includes African penguins (S. demersus), Humboldt penguins, and Galapagos penguins.

The average adult is about 70 cm in length and weighs from 4 to 4.7 kg, males being slightly taller and heavier than females. Both sexes closely resemble one another in appearance. The plumage of juvenile Magellanic penguins is coloured brown and white. Juveniles also differ from adults by possessing a single white band that separates the plumage colouring the face and stomach. Instead of a prominent crescent of white feathers on either side of the face, juveniles display light-coloured cheek patches that contrast with the darker feathers of the head. Chicks are brown with a white face and underside.

Since 2004, Magellanic penguins have been listed as near threatened on the International Union for Conservation of Nature’s Red List of Threatened Species. A census performed in 2013 estimated that there are between 1.1 million and 1.6 million breeding pairs worldwide. Some colonies have grown substantially since the 1960s, whereas others have experienced sustained population declines. For example, between the early 1960s and the early 1990s, the Caleta Valdés colony in Argentina grew from only two pairs to 26,000 pairs. In contrast, the population of the colony at Punta Tombo in Argentina fell by 20–30 percent between 1987 and 2010. In addition, some studies report that the Falkland Island population decreased by nearly 50 percent during the same period. Furthermore, during the 1980s and early 1990s, some 20,000–40,000 adults and juveniles succumbed to oil pollution each year along the coast of Argentina. Such dramatic declines have worried ecologists. Other threats to Magellanic penguins include competition with the commercial fishing industry for anchovies and other fish, inadvertent capture in fishing nets, and reproductive and food disruptions caused by El Niño/Southern Oscillation events.


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African penguin

African penguin, also called black-footed penguin, Cape penguin, or jackass penguin, is characterized by a single band of black feathers cutting across the breast and a circle of featherless skin that completely surrounds each eye. The species is so named because it inhabits several locations along the coasts of Namibia and South Africa. African penguins also possess prominent C-shaped regions of white feathers on both sides of the head. In contrast, the feathers on the back and head of juveniles are gray, and those on their underside are white. The chicks are covered in a fluff of gray to brown-gray feathers.

Humboldt penguin

Humboldt penguin, also called Peruvian penguin, is characterized by the presence of a broad C-shaped band of white feathers on the head, a wide band of black feathers that runs down the sides of the body and cuts across the white plumage of the bird’s abdomen, and a large pink fleshy region on the face. The geographic range of the species is limited to the coasts of Peru and Chile and nearby Pacific islands. This species is able to survive so close to the equator because of the biogeography of the western coast of South America. Cold, productive water travels from Antarctica via the Humboldt Current (named for the same explorer), which flows along this species’ entire distribution. The Humboldt penguin is closely related to the other temperate penguins and more distantly related to the Antarctic penguins.

African penguins have declined by more than 60 percent since the early 1980s. The blame for these losses has fallen on the commercial fishing industry, which harvests anchovies and other shoaling fishes in the region where the penguins hunt, but oil pollution and predation pressure are also important causes of mortality. The number of breeding pairs, which once exceeded 140,000 in the late 1950s, fell to 69,000 in 1980 and down to just over 25,000 by 2009. African penguins have been listed as endangered on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species since 2010.

Conservation Status Humboldt penguins have been in decline since the middle of the 19th century, and the species has been listed as vulnerable on the International Union for Conservation of Nature’s Red List of Threatened Species since 2000. There are several reasons for this, but the most significant appears to be related to the species’s extreme susceptibility to food shortages and extreme weather that accompany strong El Niño events. The most severe El Niño events on record, characterized by the 1982–83 and 1997–98 episodes, resulted in the loss of more than 60 percent of the species on each occasion. In addition, Humboldt penguins are threatened by food shortages associated with aggressive commercial fishing in the eastern Pacific Ocean, by habitat loss due to guano excavation on the islands they inhabit, by marine pollution, and by fishing net entanglement. Many individuals are hunted for food or are captured for the pet trade. In 2010 the environmental organization BirdLife International estimated that the total population ranged from 3,000 to 12,000 individuals.



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Snares penguin Snares penguin, also called Snares Island penguin or Snares crested penguin, specie characterized by plumes of yellow feathers that run above each eye (the superciliary stripe) and extend from the base of the bird’s cone-shaped bill to the back of the head. Compared with those of other species in the genus, the tips of these plumes are longer and droop off the back of the head. The species is named for the Snares Islands, the group of rocky islets it inhabits in the Southern Ocean near New Zealand. Although breeding populations are limited to the Snares Islands, migrating individuals have traveled as far as Australia and the Falkland Islands. Snares penguins are often confused with Fiordland penguins and erect-crested penguins (E. sclateri).

Conservation Status

Predators And Prey The diet of Snares penguins is not well documented, but ornithologists believe that it is mostly made up of krill; however, squid and fish are also eaten. They are relatively fast swimmers, reaching speeds of perhaps up to 24 km (15 miles) per hour in pursuit of their prey. At sea, adults are sometimes preyed upon by Hooker’s sea lions (Phocarctos hookeri). On land, however, eggs and chicks are more vulnerable, falling prey to skuas (Catharacta) and giant fulmars (Macronectes giganteus).

In 2008 ecologists estimated that the Snares penguin population totaled 26,000 breeding pairs, with most of the birds living on North East Island, the largest island in the group. Compared with other species in the genus, the population is thought to be relatively stable. (It fluctuated between 23,000 and 30,000 breeding pairs between 1985 and 2008.) This relative stability has been attributed to the remoteness of the islands coupled with New Zealand’s strict rules regarding who can visit them. (Access to the islands is given only to scientific expeditions with special permits.) As a result, the Snares Islands are free from invasive mammals—such as rats, rabbits, foxes, and feral dogs and cats—that plague the habitats of several other penguin species. Since 1994, however, the species has been listed as vulnerable on the International Union for Conservation of Nature’s Red List of Threatened Species because of its limited breeding range.


Penguins

Fiordland Penguin Fiordland penguin, also called Fiordland crested penguin is a specie of crested penguin characterized by a thick stripe of pale yellow feather plumes above each eye (the superciliary stripe) that extends from the bill to the rear of the head. The terminal ends of each of the stripes extend outward near the back of the head. The species is also distinguished by a patch of bare skin at the base of its bill. It breeds on Stewart Island, Solander Island, and much of the western and southern coasts of the South Island in New Zealand. (Fiordland is located on the westernmost tip of the South Island.) However, individuals have migrated as far away as the North Island of New Zealand, Tasmania, and the Australian mainland.

Conservation Status Ecologists note that Fiordland penguins have declined since the early 1980s because of predation pressure on eggs and chicks. Breeding pairs once numbering 5,000 to 10,000 in the mid-1980s had fallen to 2,500 to 3,000 by 2010. Colonies on the South Island have experienced the largest declines because of their vulnerability to terrestrial predators and the loss of breeding sites resulting from habitat fragmentation caused by humans. The International Union for Conservation of Nature has listed Fiordland penguins as vulnerable since 1994 on the IUCN Red List of Threatened Species.

Predators And Prey The species subsists on fish larvae, small fish, crustaceans, cephalopods, and krill. On land, predators of the Fiordland penguin include dogs, cats, stoats, wekas, and ferrets. In places where such predators are abundant, such as on the South Island, egg and chick mortality is often high. In the ocean, adults and juveniles are occasionally preyed upon by Hooker’s sea lions; however, their effect on Fiordland penguin populations is small.


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Erect-crested penguin Erect-crested penguin, is a specie characterized by plumes of yellow feathers extending from the bill to the back of the head, running above each eye (the superciliary stripe); the plumes often stand fully upright at the top of the head. Although some members of the species are found along the coasts of Australia, New Zealand, and nearby islands in the Southern Ocean (such as the Auckland Islands, Campbell Island, and Macquarie Island), breeding populations are limited to the Antipodes Islands and Bounty Islands near New Zealand. Erect-crested penguins are often confused with Fiordland penguins and Snares penguins.

Physical Features Standing up to 67 cm (26 inches) tall and weighing as much as 6 kg (about 13 pounds), E. sclateri is among the largest of the six species of crested penguins. Although males are slightly larger than females, adult members of both sexes have black heads, black throats, black backs, and white undersides. The backs of the flippers are coloured black, whereas the undersides are coloured white with black tips. Chicks are brown with white undersides, and juveniles are somewhat smaller than adults, possessing shorter, paler crests and paler chins.

Conservation Status

Ecologists note that the number of erect-crested penguins has been declining since at least the late 1970s. On the Bounty Islands the number of breeding pairs fell from 115,000 in 1978 to 28,000 by 1998. On the Antipodes Islands the population decrease has been less severe, falling from roughly 115,000 breeding pairs in 1978 to between 49,000 and 57,000 breeding pairs in 1995. In addition, evidence of successful breeding on Campbell Island and the Auckland Islands has not been seen since at least the 1980s. The International Union for Conservation of Nature (IUCN) notes on its Red List of Threatened Species that the greater population continued to decline into the early 21st century, and since 2000 the IUCN has listed the species as endangered. Thus far scientists have not been able to identify the reasons for the decline, but they have been able to rule out excessive mortality associated with hunting or introduced predators.

Predators And Prey The species is thought to subsist on krill and fish, but no reliable observations of its feeding habits have been made. Adults sometimes fall prey to Hooker’s sea lions in the ocean. On land eggs and chicks are more vulnerable, falling prey to skuas and possibly mice.


Penguins

Conservation Status Since 1988 the blue penguin has been listed as a species of least concern on the International Union for Conservation of Nature’s Red List of Threatened Species. Ecologists base this classification on the species’s high numbers and extremely large geographic range. Although a definitive population count has not been performed, several studies estimate the population at more than one million blue penguins worldwide, with the majority located in Australia. On the other hand, the population of some colonies has declined from the effects of introduced predators, increased competition with commercial fishing for food resources, and habitat fragmentation brought about by building and road construction.

Blue penguin Blue penguin, also called little penguin, little blue penguin, or fairy penguin, specie of penguin characterized by its diminutive stature and pale blue to dark gray plumage. It is the smallest of all known penguin species, and it is the only species of the genus Eudyptula. There are, however, six subspecies: E. minor novaehollandiae inhabits mainland Australia and Tasmania, while E. minor minor, E. minor iredelai, E. minor variabilis, E. minor albosignata, and E. minor chathamensis are native to the islands of New Zealand.

Across all subspecies, adults average about 25–30 cm (about 10–12 inches) in length and weigh between 1 and 1.5 kg (about 2.2 and 3.3 pounds), with males being slightly longer and heavier than females. The colour of the plumage covering the top of the head, neck, back, and tops of the flippers ranges from indigo to gray, which contrasts with the white undersides. Juveniles are similar to adults in size, but their feathers are lighter in colour. The downy feathers of chicks are coloured black and brown.


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Yellow-eyed Penguin

Yellow-eyed penguin, the only species of penguin (order Sphenisciformes) belonging to the genus Megadyptes and the only one characterized by pale yellow eyes, yellow eyebands, and yellow feathers that cover the upper part of the head. The geographic range of the species is limited to Stewart Island, the Auckland Islands, Campbell Island, and the southeastern coast of South Island in New Zealand.

Physical Features

Adult yellow-eyed penguins average about 60 cm in length and weigh from 5 to 6 kg, the males being slightly taller and heavier than the females. Both sexes closely resemble one another in appearance, possessing gray plumage on their back and white plumage on their underside. The irises are coloured gray at the beginning of the juvenile stage, but they change to yellow before full adult plumage is developed. Chicks are covered with dark brown downy feathers.

Predators And Prey

Yellow-eyed penguins prefer squid and fish, especially red cod and blue cod, bristling, and silversides. Individual yellow-eyed penguins routinely dive as deep as 130 metres beneath the ocean’s surface to capture prey. In the ocean, adults and juveniles are killed and eaten by sharks and Hooker’s sea lions. On land, eggs and members of all age classes are preyed upon by introduced predators, such as ermines, ferrets, and domesticated and feral dogs and cats.

Conservation Status

Ornithologists and ecologists contend that the worldwide population has declined dramatically since 1960. By 2010 the species was made up of only 4,000–4,800 adults, which included approximately 1,500 breeding pairs. The species has been listed by the International Union for Conservation of Nature (IUCN) as endangered since 2000 on the IUCN Red List of Threatened Species.

The IUCN justifies the classification by citing a number of threats that contributed to the species’s decline. Each year, many yellow-eyed penguins die from entanglement in fishing nets, predation by introduced mammals, and infections by blood parasites and avian malaria. Periodically, the populations of some colonies have fallen from food shortages resulting from cyclical changes in seawater temperature and diphtheritic stomatitis (a disease caused by bacteria that produces mouth lesions in chicks that hinder swallowing and respiration). In addition, the species is limited to small habitat patches, many of which have declined in quality as a result of residential development and other human activities. However, some studies note that the combined effects of penguin awareness campaigns (such as the Yellow-eyed Penguin Trust), barriers that prevent humans from disturbing the nests, aggressive predator trapping, and habitat restoration may have arrested the decline in habitat quality, which may lead to increases in population over time.


South Pole

South Pole South Pole, southern end of the Earth’s axis, lying in Antarctica, about 480 km south of the Ross Ice Shelf. This geographic South Pole does not coincide with the magnetic South Pole, from which magnetic compasses point and which lies on the Adélie Coast (at about 66°00’ S, 139°06’ E; the magnetic pole moves about 13 km to the northwest each year). Nor does it coincide with the geomagnetic South Pole, the southern end of the Earth’s geomagnetic field (this pole also moves; during the early 1990s it was located about 79°13’ S, 108°44’ E). The geographic pole, at an elevation of some 9,300 feet (2,830 m; the elevation also changes constantly) above sea level, has six months of complete daylight and six months of total darkness each year. Ice thickness is 8,850 feet (2,700 m). First reached by the Norwegian explorer Roald Amundsen on Dec. 14, 1911, the pole was reached the following year by the British explorer Robert F. Scott and in 1929 by the American explorer Richard E. Byrd. The South Pole is the site of a U.S. station and landing strip (Amundsen-Scott); owing to the movement of the polar ice cap, a new location of the exact rotational pole is marked periodically by station personnel.


O n Th e Ic e E dge

Curiosities about penguins Scientists still don’t know for sure how many kinds there are. Estimates usually fall in the range of 17 to 20, as there’s still some debate over whether similar types of penguins (like rockhoppers) actually count as different species. Penguins jump into the air before diving to swim faster. The move releases air bubbles from their feathers, cutting down on drag and doubling or tripling their speed underwater, according to Smithsonian. To make the leap back ashore, some smaller penguins can launch themselves 6 or 9 feet into the air by speedily swimming to the surface and bursting up over the ice shelf. Explorers first called them “strange geese.” That’s what crew member Antonio Pigafetta wrote on Ferdinand Magellan’s first circumnavigation of the globe, Mental Floss reports. The birds he most likely spotted in the Falkland Islands now go by the name Magellanic penguins (Spheniscus magellanicus). They can swim at speeds over 10 miles per hour. Gentoos, the speediest penguins, can top 20 mph, but most species dart around at a more modest 4 to 7 mph. And also dive down over 800 feet. In the deepest dive ever recorded by the Australian Antarctic Division, an emperor penguin reached an amazing 1,850 feet. Those huge depths require a great lung capacity; the longest-known dives have lasted 22 minutes! They can drink seawater. While penguins sip meltwater from pools and streams when they’re thirsty, their hunting style and diet necessitates a cool adaptation. A supraorbital gland located above their eye removes salt from the bloodstream. The excess sodium then comes out through the bill or by sneezing! Penguins’ suits act as camouflage. Their black backs blend with the ocean water when seen from above, and the white bellies match the bright surface when viewed from below. This disguises them from predators like leopard seals and helps them catch prey like fish, squid, crabs, and krill. They go through a “catastrophic molt” once a year. Penguins lose all of their feathers during the two- to three-week process, and can’t swim or fish until the important insulation grows back.


Curiosities

Couples locate each other with distinct calls. The unique sounds help them reunite on the breeding ground — a not-so-easy task when there are thousands of identical birds around . Pudgy penguins make good mates. Because of the intense fasting involved, the females often seek out chubbier guys who can go weeks without food as the ladies take a turn to hunt for fish. A group of penguins in the water is called a raft. These avid swimmers spend up to 80% of their lives out at sea! Scientists can find penguins using poop. The abundance of dark excrement (called guano) produced by large colonies allows researchers to see the groups from space! In 2018, the smelly giveaway just revealed a 1.5 million member “super-colony” of Adelie penguins in the Danger Islands. They’re super friendly with people. Penguins’ main predators (seals, sea lions, whales, and sharks) all reside in the water, so these birds feel much safer on land around researchers and tourists — for better or for worse. Some penguins build pebble nests. Gentoo penguins’ “nests” look so ramshackle that ornithologists actually call them scrapes. The parents do line the pile of rocks with soft moss and feathers, though. Others dig out cozy burrows. Little penguins tunnel holes in the sand dunes, typically a passageway leading to a “nest bowl” just large enough to stand up in. The males and females take turns incubating the eggs and feeding the chicks until they reach about 8 or 9 weeks old. many male penguins gift female penguins with rocks in order to woo them During courtship, a male penguin will find the smoothest pebble to give to a female as a gift. If she likes the offering, she’ll place it in the nest and the two will continue building up their little pebble mound in preparation for the eggs. Of course, “pebble envy” remains a problem for some male penguins who just can’t find the right rock on their own. Instead, they will steal the best-looking pebbles from another penguin and pawn them off as their own. They love “tobogganing.” Instead of shuffling across the ice, many penguins like to lay on their stomachs and propel themselves with their feet. It’s often a faster way to get around and it’s just plain fun, okay?



Ficha Tecnica Editor: João Carneiro Director: João Carneiro Advertising: João Carneiro Designer: João Carneiro Images: Pinterest



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