The king penguin ( Aptenodytes patagonicus) is the second largest species of penguin, smaller than but somewhat similar in appearance to the emperor penguin.
King penguins mainly eat lanternfish, squid, and krill. On foraging trips, king penguins repeatedly dive to over , and have been recorded at depths greater than . Predators of the king penguin include , skuas, the snowy sheathbill, the leopard seal, and the orca.
The king penguin breeds on the subantarctic islands at the northern reaches of Antarctica, South Georgia, southern Argentina, and other temperate islands of the region. It also lives on Macquarie Island in the Southern Ocean and the Falkland Islands.
This bird was exploited commercially in the past for its blubber, oil, meat, and . Today it is fully protected.
The International Ornithologists' Union considers the species monotypic, recognizing no subspecies. However, some taxonomic authorities recognize two subspecies, A. p. patagonicus and A. p. halli; in this system, patagonicus is found in the South Atlantic and halli in the South Indian Ocean (at the Kerguelen Islands, Crozet Island, Prince Edward Islands, and Heard Island and McDonald Islands) and at Macquarie Island.
At first glance, the king penguin appears similar to the larger, closely related emperor penguin, with a broad cheek patch contrasting with surrounding dark feathers and yellow-orange plumage at the top of the chest. However, the cheek patch of the adult king penguin is a solid bright orange whereas that of the emperor penguin is yellow and white, and the upper chest tends to be more orange and less yellowish in the king species. Both have colourful markings along the side of their lower mandible, but these tend towards pink in emperor penguin and orange in king penguin.
Emperor and king penguins typically do not inhabit the same areas in the wild, with the possible exception of vagrants at sea, but the two can be distinguished from one another by the king's longer, straighter bill, larger flippers, and noticeably sleeker body. The juvenile king penguin with its long bill and heavy dark brown down is completely different in appearance from the mostly grey emperor chick with its black and white mask. Once moulted of its brown juvenile plumage, the king chick resembles the adult, but is somewhat less colourful. The king penguin often breeds on the same large circumpolar islands as other penguin species, but it is easily distinguished from other species by its much larger size and taller frame, colorful markings, and grizzled sooty-greyish rather than blackish back.
By the early 1920s, the king penguin population in South Georgia and the Falklands was nearly wiped out by whalers on these islands. As the Falklands and South Georgia had no trees to use for firewood, the whalers burned millions of oily, blubber-rich penguins as fuel. Constant fires were required to boil whale blubber for extraction of the oil. The whalers also used penguin oil for lamps, heating and cooking, in addition to eating the birds and their eggs. Macquarie Island currently has around 70,000 pairs. The non-breeding range is unknown; many vagrant birds have been seen on the Antarctic peninsula as well as in South Africa, Australia, and New Zealand.
One of the largest known king penguin colonies, on Île aux Cochons in the Crozet Islands, experienced a massive drop in its population over the last few decades, from about half a million breeding pairs in the 1980s to about 60,000 breeding pairs in 2017. The cause of this decline may be changes in the ecosystem related to climate change as their primary source of food is moving farther away from places where the penguins can breed. This may result in population declines and shifts in the locations of the king penguin breeding grounds.
The Nature Protection Society released several king penguins at Gjesvær in Finnmark and Røst in Lofoten in northern Norway in August, 1936. Penguins were seen in the area several times during the 1940s; there were a few unconfirmed sightings of penguins in the area during the early 1950s, but none have been officially recorded since 1949.
The majority (around 88% in one study) of dives undertaken by king penguins are flat-bottomed; that is, the penguin dives to a certain depth and remains there for a period of time hunting (roughly 50% of total dive time) before returning to the surface. They have been described as U-shaped or W-shaped, relating to the course of the dive. The remaining 12% of dives have a V-shaped or "spike" pattern, in which the bird dives at an angle through the water column, reaches a certain depth, and then returns to the surface. In contrast, other penguins dive in this latter foraging pattern.Williams, pp. 87–88 Observations at Crozet Islands revealed most king penguins were seen within of the colony. Using the average swimming speed, Kooyman estimated the distance travelled to foraging areas at .
The king penguin's average swimming speed is . On shallower dives under , it averages descending and ascending, while on deeper dives over deep, it averages in both directions. King penguins also "porpoise", a swimming technique used to breathe while maintaining speed. On land, the king penguin alternates between walking with a wobbling gait and tobogganing—sliding over the ice on its belly, propelled by its feet and wing-like flippers. Like all penguins, it is flightless.Williams, p. 3
The king penguin has a prolonged breeding cycle, taking around 14–16 months from laying to offspring fledging.Williams, p. 148 Although pairs will attempt to breed annually, they are generally only successful one year in two, or two years in three in a triennial pattern in South Georgia. The reproductive cycle begins in September to November, as birds return to colonies for a prenuptial moult. Those that were unsuccessful in breeding the previous season will usually arrive earlier. They then return to the sea for around three weeks before coming ashore in November or December.Williams, p. 149
The female penguin lays one pyriform (pear-shaped) white egg weighing .Williams, p. 150 It is initially soft but hardens and darkens to a pale greenish colour. It measures around . The egg is incubated for around 55 days with both birds sharing incubation in shifts of 6–18 days each. Like the closely related emperor penguin, the king penguin balances the egg on its feet and incubates it in a brood pouch.
Hatching may take up to 2–3 days to complete and chicks are born altricial: they have only a thin covering of down, and are entirely dependent on their parents for food and warmth. The guard phase begins with the hatching of the chick. Like that of the emperor penguin, the young king penguin chick spends its time balanced on its parents' feet, sheltered in the brood pouch formed from the abdominal skin of the latter.Williams, p. 28 During this time, the parents alternate every 3–7 days, one guarding the chick while the other forages for food. The guard phase lasts for 30–40 days. By then the chick has grown much larger and is better able to both keep warm and protect itself against most predators. King chicks are very curious and will wander far when exploring their surroundings. The chicks form a group called a crèche and are watched over by only a few adult birds; most parents leave their chick in these crèches to forage for themselves and their chick. Other species of penguins also practice this method of communal care for offspring.
By April, the chicks are almost fully grown but lose weight while fasting over the winter months, gaining it again during spring in September. Fledging then takes place in late spring/early summer.
King penguins form huge breeding colonies; for example, the colony on South Georgia Island at Salisbury Plain holds over 30,000 breeding pairs and the colony at St. Andrew's Bay holds over 150,000 pairs. Because of the long breeding cycle, colonies are occupied year-round with both adult birds and chicks. During breeding, king penguins do not build nests, although they show strong territorial behaviour and keep a pecking distance to neighbouring penguins. Penguin positions in breeding colonies are highly stable over weeks and appear regularly spaced.
The king penguin feeds its chicks by eating fish, digesting it slightly, and regurgitating the food into the chick's mouth.
Because of their large size, king penguin chicks take 14–16 months before they are ready to go to sea. This is markedly different from smaller penguins, who rear their chicks through a single summer when food is plentiful. King penguins time their mating so the chicks will develop over the harshest season for fishing. In this way, by the time the young penguins are finally mature enough to leave their parents, it is summer when food is plentiful and conditions are more favorable for the young to survive alone at sea.
King penguins primarily feed at the Antarctic Convergence, which provides 80% of their food biomass. King penguins currently travel 300–500 km over the course of over a week to complete the journey. However, ocean warming could easily move these fronts further away from breeding grounds. Continuous ocean warming could cause the convergence zone to move polewards, away from king penguin breeding sites like the Falklands and the Crozet Islands. It has been suggested that if carbon emissions continue to rise at their current rate, king penguins will need to travel an additional 200 km in order to reach their feeding areas. Breeding grounds will also suffer from the rise of emissions. Nearly half of the total population will likely lose their breeding grounds by the year 2100.
The species is classified as Least Concern by the International Union for Conservation of Nature's Red List of Threatened Species. Since 2004, the IUCN has reported that the population size is large and has increased its breeding rates. Adult king penguins have maintained high survival rates since the 1970s. The steady population of king penguins is due largely to current conservation efforts to protect nesting habitats. Ecotourism and public access to all king penguin breeding sites are heavily restricted in order to prevent outbreaks of disease and general disturbance. All of the colonies in Crozet and Kerguelen Islands are protected under the oversight of the Reserve Naturelle Nationales des Terres australes et Antarctiques Françaises. South Georgian penguins reside in a "special protected area within the Environmental Management Plan for South Georgia." And in the Falklands, all wildlife—including the king penguin—is protected under the Conservation of Wildlife and Nature Bill of 1999.
Diet
Predators
Courtship and breeding
Conservation
Impact of climate change
Resource competition
Research and management
Relationship with humans
In captivity
Notable king penguins
Footnotes
Sources cited
External links
Johann R. Forster, "Historia Aptenodytae: Generis Avium Orbi Australi Propri", Commentationes Societatis Regiae Scientiarum Gottingensis (1778), Vol.III, 1781, pp. 211–148.
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