This is not a photo of a penguin, but at least it is a bird.
PENGUINS
Penguins are birds, all in the class AVES. Birds:
have an outer covering of feathers,
are endothermic/warm blooded,
have front limbs modified into wings, and
lay eggs.
All living and extinct penguins belong to the order Sphenisciformes, with the single family, Spheniscidae.
Most scientists recognize 17 species of penguins: the *emperor; *king; *Adelie; *gentoo; chinstrap; rockhopper; *macaroni; royal; Fiordland crested; erect crested; Snares Island; yellow-eyed; fairly/little blue; *Magellanic; *Humboldt (not on display yet); African/black-footed; and Galapagos. * indicates the ones that are at Sea World,
Fossil record:
40 or more species of extinct penguins.
Penguins evolved from flying birds more than 65 million years ago during the Cretaceous Period.
As the ancestors of penguins became more adapted to an oceanic environment, structural changes for diving and swimming led to the loss of flying adaptations.
To date, all penguin fossil fragments have been limited to the Southern Hemisphere. Records show that prehistoric penguins were found within the range of present day penguins.
v The earliest penguin fossil fragments were found in
v The oldest penguin fossils date from 58->60 million years ago.
v The largest extinct species lived in the Miocene Period (11-25 million years ago). These stood 4-5 feet tall and weighed 200-300 pounds). These measurements are approximate, since only a few bone fragments have been found.
The extinct species of penguins started disappearing during the Miocene, about the same time that the number of prehistoric seals and small whales started increasing in the oceans.
v One hypothesis is that seals, whales, and penguins may have competed for the same food source.
v Another hypothesis is that penguins could have become prey for some of these other predators.
Discovery of modern penguins:
The first European explorers to see penguins probably were part of the Portuguese expedition of Bartholomeu Dias de Novaes in 1487-88. They were the first to travel around what is now known as the Cape of Good Hope in southern
The first documentation of penguin sightings is credited to members of the Portuguese voyage of Vasco de Gama to
The discovery of
The origin of the word “penguin” has been a subject of debate. The theories of researchers and historians range from references to the amount of fat (“penguigo” in Spanish and “pinguis” in Latin) penguins possess to the claim that the word was derived from two Welsh words meaning “white head.” The most agreed upon explanation is that “penguin” was used as a name for the now extinct great auk, which the modern day penguin resembles and for which it was mistaken.
Distribution and habitat:
All 17 species of penguins live in the Southern Hemisphere. They are found on every continent in the Southern Hemisphere. They are abundant on many temperate and subantarctic islands.
Penguins generally live on islands and remote continental regions, free from land predators, where their inability to fly is not detrimental to their survival.
These highly specialized marine birds are adapted to living at sea—some species spend as much as 75% of their lives at sea. Penguins are usually found near nutrient-rich, col-water currents that provide and abundant supply of food.
Different species thrive in varying climates, ranging from Galapagos penguins on tropical islands at the equator to emperor penguins restricted to the pack ice of
The seasons of the Southern Hemisphere are opposite to those in the Northern Hemisphere. When continents above the equator experience spring and summer, the areas below the equator are experiencing fall and winter.
Migration: adult penguins usually disperse from breeding rookeries to fed in coastal waters. Studies have found that adult emperor, Magellanic, and Humboldt penguins travel long distaces between feeding and breeding grounds. Young birds usually disperse when they leave their colonies and may wander thousands of kilometers. They generally return to the colonies where they were hatched to molt and breed.
Population: Data are usually gathered during the breeding season. Some researchers count chicks to estimate the total population, whereas others count breeding pairs. Estimates range from Chinstrap penguins, estimated at 4 million breeding pairs, to 4,840 mature individuals in the yellow-eyed penguin populations.
Size: the emperor penguins is the largest, standing 3.7 feet tall and weighing 60-90 pounds. The smallest is the fairy penguin, standing a mere 16 inches tall and weighing only 2.2 pounds.
Body shape: the penguin’s body is adapted for swimming, with the body shape being fusiform and streamlined. A penguin has a large head, short neck, and elongated body. The tail is short and wedge-shaped. The legs and webbed feet are set far back on the body, which gives the penguins their upright posture on land.
Coloration:
All are countershaded, dark on the dorsal surface and white on the ventral surface.
The emperor has a black head, chin, and throat, with broad yellow patches on each side of the head.
The king penguin has a black head, chin, and throat, with vivid orange, tear-shaped patches on each side of the head. The orange coloration extends to the upper chest.
The Adelie has a black head. Distinctive white eye rings appear during the breeding season.
The gentoo has a black head with white eyelids, and a distinct triangular white patch above each eye, usually extending over the head.
The top of a chinstrap’s head is black and the face is white, with a stripe of black extending under the chin, and hence its name.
The crested penguins, such as the rockhopper and macaroni, are distinguished by orange or yellow feather crests on the sides of the head, above the eyes.
The yellow-eyed penguin, as the name suggests, has yellow eyes and a stripe of pale yellow feathers extending over its dark head.
The fairy penguin, also known as the little blue, has slate-blue to black feathers and a white chin and chest.
Temperate penguins, such as the Humboldt and Magellanic, have unfeathered fleshy areas on the face and 1-2 distinct black stripes across the chest.
Chicks, juveniles, and immature penguins may have slightly different markings than adults. Generally, they appear duller in color than adults; adult markings take a year or longer to develop.
Sexual dimorphism: generally, penguins are not sexually dimorphic; males and females look alike. Crested penguins are exceptions in that the males are more robust and have larger bills than the females.
Flippers:
v Wings are modified into paddlelike flippers. The bones are flattened and broadened, with the joint of the elbow and wrist almost fused. This forms a tapered, flat flipper for swimming.
v Each flipper is covered with short, scale-like feathers. The long wing feathers typical of most birds would be too flexible for swimming through water.
v Penguins propel themselves through the water by flapping their flippers.
Head:
Different species of penguins can be identified by their head and facial markings.
Penguins have a variety of bill shapes. A penguin captures fish, squid, and crustaceans with its bill.
v Generally, the bill tends to be long and thin in species that are primarily fish eaters.
v The bill is shorter and stouter in those that mainly eat krill.
The mouth is lined with horny, rear-directed spines to aid in swallowing live prey.
Eyes:
v The color varies with species.
v Many have brown, reddish-brown, or golden-brown eyes.
v Rockhopper and macaroni penguins have red eyes.
v Fairy/little blue penguins have bluish-gray eyes.
v Yellow-eyed penguins, of course, have yellow eyes.
v The pupil of a penguin’s eye is circular. Then constricted, however, the pupils of the king penguin are square.
v Like many animals, penguins have a nictitating membrane, sometimes called a third eyelid. This is a clear covering that protects the eye from injury.
Legs and feet:
Penguins legs are short and strong.
Feet are webbed, with visible claws.
The legs are set far back on the body to aid in streamlining and steering while swimming. This placement also causes penguins to stand vertically and walk upright.
Penguins walk with short steps or hops, sometimes using their bills or tails to assist them on steep climbs.
o The maximum walking speed for Adelie penguins is 2.4 mph.
o Emperor and king penguins walk slowly and do not hop. The maximum walking speed is 1.7 mph.
o Some species, like the rockhopper penguin, jump from rock to rock.
When traveling on ice, Antarctic penguins often “toboggan” on their bellies. They use their flippers and feet to slide their bodies forward along the ice.
Tail: a penguin’s tail is short and wedge-shaped, with 14-18 stiff tail feathers. Adelie, gentoo, and chinstrap penguins have longer tail feathers (collectively known as brush tailed penguins), which they often use as a prop when on land.
Feathers:
Shiny feathers uniformly overlap to cover a penguin’s skin. Penguin feathers are highly specialized—short, broad, and closely spaced. This keeps water away from the skin. Tufts of down on the feather shafts increase the insulative properties of the feathers.
Penguins have more feathers than most other birds, with about 100 feathers per square inch.
Most species go through one complete molt per year, usually after the breeding season. The exception is the Galapagos penguin, which usually goes through 2 molts per year.
Molting is essential because feathers wear out during the year. Feathers become worn when penguins rub against each other, come in contact with the ground and water, and regularly “preen” (clean, rearrange, and oil) their feathers.
The new feather grows under the old one, pushing it out. The old feather does not fall out until the new one is completely in place. The molt is patchy and can give individual penguins a scruffy look.
During the molt, feathers lose some of their insulating and waterproofing capabilities, and penguins thus stay out of the water until their plumage is restored to optimal condition.
Depending on the species, the average length of the molt period varies between 13 days (Galapagos penguin) to 34 days (emperor).
Penguins fast when molting. Prior to this, they build up a layer of fat to provide energy until the molt is complete.
Senses:
v Hearing: as in most birds, penguin hearing is probably good, but not as acute as that of marine mammals. Hearing in penguins has not been well researched, but vocalization has since it is important for communication and mate recognition.
v Eyesight: a penguin’s eyes are adapted to see clearly both in air and under water. They have color vision.
v Taste: In general, the sense of taste in birds is poorly developed.
v Smell: a penguin’s sense of smell may be more developed than early studies indicated. The olfactory lobe of a penguin’s brain is large. Studies on captive Humboldt penguins indicate that this species may have some sense of smell.
Adaptations for an aquatic environment:
Swimming:
· Some species spend as much as 75% of their lives in the sea. They may spend several months at a time at sea, only coming ashore for breeding and molting. The Fiordland crested penguins occasionally grow barnacles on their tails, an indication that they are at sea for long periods.
· Swimming speeds generally are not well known. Earlier estimates of swimming speeds were taken from observations of penguins swimmig alongside moving ships, a method that proved to be unreliable. The fastest swimmers belong to the genus Aptenodytes. Emperors have been observed swimming 9 mph, though they normally do not exceed 6.7 mph. Both kings and chinstraps have been recorded at 5.3 mph. Adelie penguins reach speeds of 4.9 mph. Fairy penguins swim slower at about 1.6 mph.
· A penguin hunches its head into its shoulders to maintain its streamlined shape and reduce drag while swimming. It keeps its feet pressed close to the body against the tail to aid in steering.
· Penguin wings are paddlelike flippers used for swimming. The motion of the flippers resembles the wing movements of flying birds, giving penguins the appearance of flying through water. The wing and breast muscles are well developed, to propel penguins through water—a medium much denser than air.
· Having solid, dense bones helps penguins overcome buoyancy.
· Although it is more energy efficient for penguins to swim under water than at the water’s surface, they must come to the surface to breathe. Many species of penguins porpoise—leap in and out of the water, like dolphins or porpoises.
· When porpoising, penguins can continue breathing without interrupting forward momentum. They maintain a steady speed of 4.3-6.2 mph. Porpoising also may confuse underwater predators.
· Not all species exhibit this behavior. Emperor penguins are not known to porpoise and this behavior is infrequently seen in king penguins.
Diving:
· Most prey of penguins inhabit the upper water layers, so penguins generally do not dive to great depths or for long periods.
o Most species stay submerged less than a minute.
o Gentoo and Adelie penguins have been recorded staying under water for 7 minutes.
o Chinstraps can reach depths of 100 meters, but most divers are less than 30 m. Nearly half are less than 10 m. and last between 20-30 seconds.
o Most dives of king penguins last less than 4-6 minutes, although dives of nearly 8 minutes have been documented. The maximum recorded depth for a king penguin dive was 304 m/997 feet.
· Studies using radio tracking and automatic depth records reveal that emperor penguins sometimes hunt at great depths.
o Emperors hunt fast midwater squids and fishes and therefore tend to dive more deeply and remain submerged longer than other penguins.
o The deepest dive recorded for an emperor penguin was 535 m/1,755 feet. The longest recorded dive for an emperor penguin was 22 minutes. Most dives are within 21 m/70 ft of the surface and last 2-8 minutes.
· During deep dives, the penguin heart rate slows.
· Under experimental diving conditions, penguins exhibit reduced peripheral blood flow.
· The temperature of a penguin’s peripheral areas (limbs and skin) drop during a dive while those of the core regions are maintained at the normal temperatures.
Respiration: when swimming, penguins inhale and exhale rapidly at the surface. Just before a dive, penguins inhale and then dive on a breath of air.
Salt secretion: penguins have glands under the eyes that help rid the body of excess salt. The secretion of salt and fluid often collect as droplets on the bill are are shaken off. These glands are so effective that penguins can drink sea water without ill effects.
Sleep:
· A penguin typically sleeps with its bill tucked behind a flipper, which some scientists believe serves no known purpose in penguins, but is a remnant of ancestral relations to flighted birds. Other researchers believe the behavior may reduce the amount of heat lost through the face, particularly the nostrils.
· To conserve energy while fasting, penguins may increase the time they spend sleeping.
· During the Antarctic winter, when the period of darkness may last more than 20 hours, huddling emperor penguins that are incubating eggs may sleep for most of a 24 hour period.
Thermoregulation:
· The internal temperature range of penguins is 37.8-38.9 C. (100-102 F).
· Overlapping feathers create a surface nearly impenetrable to wind or water. Feathers provide waterproofing critical to penguins’ survival in water that may be as cold as -2.2 C (28 F) in the Antarctic. Tufts of down on feather shafts trap air. This layer of air provides 80-84% of the thermal protection for penguins. The layer of trapped air is compressed during dives and can dissipate after prolonged diving. Penguins rearrange their feathers by preening.
· To conserve heat, penguins may tuck in their flippers close to their bodies. They also may shiver to generate additional heat.
· A well defined fat layer improves insulation in cold water, but probably is ot enough to keep body temperatures stable at sea for long. Penguins must remain active while in water to generate body heat.
· Penguins in colder climates tend to have longer feathers and a thicker fat layer than those in warmer climates.
· The dark plumage of a penguin’s dorsal surface absorbs heat from the sun, which increases body temperature.
· On land, king and emperor penguins tip up their fet, and rest their entire weight on their heels and tail, reducing contact with the icy surface.
· Emperor penguins huddle together to conserve heat. As many as 6,000 males will cluster while incubating eggs during the middle of the Antarctic winter.
· Emperor penguins are able to recapture 80% of heat escaping in their breath through a complex heat exchange system in their nasal passages.
· On land, overheating may sometimes be a problem.
o Penguins may prevent overheating by moving into shaded areas and by panting.
o Penguins can ruffle their feathers to break up the insulating layer of air next to the skin and release heat.
o If a penguin is too warm, it holds its flippers away from its body, so both surfaces of the flippers are exposed to air, releasing heat.
o Temperate species, like Humboldt and African penguins, lack feathers on their legs and have bare patches on their faces. Excess heat can dissipate through these unfeathered areas.
· A penguin’s circulatory system adjusts to conserve or release body heat to maintain body temperature.
o To conserve heat, blood flowing to the flippers and legs transfers its heat to blood returning to the heart. This countercurrent heat exchange helps ensure that heat remains in the body.
o If the body becomes too warm, blood vessels in the skin dilate, bringing heat from within the body to the surface, where it is dissipated.
Social behavior:
Among the most social of all birds. All species are colonial
May swim and feed in groups, but some may be solitary when diving for food. Emperor penguins have been observed feeding in groups with coordinated diving.
During breeding season, penguins come ashore and rest in huge colonies called rookeries. Some rookeries include hundreds of thousands of penguins and cover hundreds of square kilometers.
Penguins exhibit intricate courting and mate recognition behavior. Elaborate visual and vocal displays help establish and maintain nesting territories.
Although king penguins are highly gregarious at rookery sites, they usually travel in small groups of 5-20 individuals.
Penguins communicate by vocalizing and performing physical behaviors called “displays.” They use many vocal and visual displays to communicate nesting territories and mating information. They also use displays in partner and chick recognition and in defense against intruders.
Individual behavior:
Navigation: studies of Adelie penguins indicate that they use the sun to navigate from land to sea. They adjust for the sun’s changing position in the sky throughout the dya.
Preening:
· Penguins preen their feathers frequently. Feathers must be maintained in prime condition to ensure waterproofing and insulation.
· Penguins preen with their bills. A gland near the base of the tail secretes oil that the penguin distributes throughout its feathers.
· Penguins preen for several minutes in the water by rubbing their bodies with their flippers while twisting and turning.
Communication:
Vocalization:
· Penguin calls are individually identifiable, allowing mates to recognize each other and also their chick. This is important because members of a large colony of penguins are nearly indistinguishable by sight.
· Research has identified differences in the calls of male and female emperor penguins. These differences probably function in courtship and mate selection.
· 3 main kinds of penguin calls:
o Contact call assists in recognition of colony members.
o Display call is the most complex of all the calls and is used between partners in a colony. The call must convey information on territorial, sexual, and individual recognition.
o Threat call is the simplest and is used to defend a territory and warn other colony members of predators.
Displays: penguins communicate by vocalizing and performing physical behaviors called displays. They use many vocal and visual displays to communicate nesting territories, mating information, nest relief rituals, partner and chick recognition, and defense against intruders.
Food and foraging:
Preferences and resources:
· Penguins eat krill, squids, and fishes. Various species of penguins have slightly different food preferences, which reduce competition among species.
· The smaller penguin species of the Antarctic and the subantarctic primarily feed on krill and squids. Species found farther north tend to eat fishes.
· Adelie penguins feed primarily on small krill, while chinstraps forage for large krill.
· Emperor and king penguins mainly eat fishes and squids.
Food intake: intake varies with the quantity and variety of food available from different areas at different times of the year. A colony of 5 million Adelie penguins may eat nearly 17.6 million pounds of krill and small fishes daily.
Method of collecting and eating food:
· Feed at sea. Most feeding occurs within 50-60 feet of the surface. The location of prey can vary seasonally and even daily.
· Penguins primarily rely on their vision while hunting. It is not known how penguins locate their prey in the darkness, at night, or at great depths. Some scientists theorize that penguins are helped by the bioluminescence capabilities of many oceanic squids, crustaceans, and fishes.
· Penguins catch prey with their bills and swallow it whole while swimming. A penguin has a spiny tongue and powerful jaws to grip slippery prey.
· Different species travel various distances from the colony in search for food. Homing areas may range from 9 miles from the colony for Adelies and 559 miles for kings. Emperor penguins may cover 102-903 miles in a single foraging trip.
· Penguins walk and toboggan from feeding grounds to rookeries. When fishing grounds are far away, penguins will feed in seal holes and other openings in the ice.
Fasting:
· Go through annual fasting periods. Prior to fasting, penguins build up a layer of fat, which provides energy.
· Prolonged periods during breeding season; they do not leave the nesting areas to feed. Some penguins fast throughout the entire courtship, nesting, and incubation periods.
· Also fast during annual molting periods. The temporary reduction in insulation and waterproofing caused by the loss of feathers during a molt prohibits penguins from entering the water to feed.
· Chicks fast near the time they are ready to shed juvenile feathers for adult plumage. Usually by this time, the parents no longer are feeding the chick. Growth stops during this fasting period, but resumes once the molt is complete.
· The length of fasting depends on penguin species, sex, and type of fasting. The kings and emperors have the longest fasting periods.
· Breeding male kings may fast for up to 54 days during courtship and the first incubation shift. Emperors may fast 90-120 days during courtship, breeding, and the entire incubation period.
Reproduction:
Sexual maturity: like most seabirds, penguins tend to be long lived. They may take 3-8 years to reach sexual maturity. With some of the smaller species, breeding may begin at 3-4 years, but most larger species are not accomplished breeders until much later. On average, breeding does not begin until the 5th year, and a few males do not breed until the 8th year.
Mating activity:
· Breeding seasons differ from species to species.
o Most have an annual breeding season—spring thru summer.
o Kings have the longest breeding cycle of all species, lasting 14-16 months. A female king may produce a chick during alternate breeding periods..
o Emperors breed annually during the Antarctic winter, June through August. During its breeding season, air temperatures may drop to -76 degrees F and winds may reach speeds up to 124 mph. For most of the winter, Antarctic penguins live in an environment of darkness or half light. Why emperors breed during the harshest season of the year is unknown, but some scientists speculate that when the chicks become independent 5 months later in January and February, environmental conditions are most favorable for the young birds.
o The fairy penguins breeds throughout the year and has the shortest breeding cycle, which lasts about 50 days.
o Some of the temperate penguins tend to nest throughout the year.
· Courtship: varies among species. Generally begins with both visual and auditory displays. In many species, males display first to establish a nest site and then to attract a mate. Not all species exhibit all displays, but in general, there are 3 distinct types of displays.
o Ecstatic: also called trumpeting, head swinging, or advertisement, this display establishes possession of a nest site, attracts females, and warns other males to stay away. Males at the nest sit commonly exhibit the ecstatic display before females arrive. The male may dip its head low and then outstretched and squawk or “bray.” Some, like the Adelie, chinstrap, and crested species, may swing their head or flap their flippers while calling.
o Mutual: once paired, male and female penguins perform the mutual display together. This seems to strengthen the pair bond. Similar to the ecstatic display—head and neck stretched upward with a braying vocal. Crested, brush-tailed, and temperate penguins stand facing each other, performing the action in unison. Mutual displays continue throughout the breeding season, often taking place at the nest when parents switch places for egg incubation and chick feeding.
o Bowing: bowing displays may lessen the likelihood of aggression and strengthen recognition between partners. One or both of the penguins dips its head and points its bill at the nest or at the other bird’s feet.
o Most species are monogamous during a mating season; however, research has shown that some females may have 1-3 partners in one season and some males have have 1-2 partners.
o Mate selection is up to the female, and it is the females that compete for the males.
o In some species, a female selects the same male from the preceding season to mate with.
o When a female selects a different mate, it is usually because her mate from the previous season fails to return to the nesting site.
Nesting: when it is time to breed, mature birds return to the rookery where they hatched. This results in large numbers of birds at a single rookery rather than colonizing new areas. Some rookeries number millions of birds.
Nesting habitats vary from species to species.
Eggs: white to bluish or greenish. Shape varies among species, from more or less round to pear-shaped. Size and weight varies with species: emperors eggs are 4.4-5 inches long and weight 12-18 ounces; Adelie penguins eggs measure 2.2-3.4 inches long and weigh 2.1-5.4 ounces.
The egg clutch usually contains 2 eggs (only 1 in kings and emperors).
Incubation: time spent warming the egg before it hatches. With the exception of the emperors, partners take turns incubating eggs, allowing each mate to leave to feed for several days at a time.
v A female emperor’s penguin transfers a single egg to the top of her mate’s feet. The female goes to sea to feed while the male incubates the egg. She returns several weeks later, usually just before the gg is ready to hatch, to relieve her mate so that he may feed. The male fasts throughout the courtship, nesting, and incubation periods. He lives off reserves of body fat which may be 1.2-1.6 inches thick, and loses up to 45% of his body weight.
v The incubation period varies with species. It may be as short as 1 month, or as long as 2 months (62-66 days) for emperors.
v Incubation temperature is about 36 degrees C/96.5 degrees F; a bit lower for the larger species. Emperors can maintain an incubation temperature of 31 C/87.8 F in an environment that is -60 C/-76 F.
v The greatest single cause for reproductive failure in some species is the mistiming between parents for nest relief during incubation. This usually occurs when the female fails to return from a foraging trip before the male deserts the nest. A male will spontaneously leave the nest and eggs when the motivation to feed overcomes that for incubating eggs.
v Hatching:
Ø Chicks first “pip” by poking a small hole in the egg. They then chip at the shell until they can push off the top. Chicks take up to 3 days to chip their way out.
Ø Fine down feathers cover most newly hatched chicks.
Ø Down feathers of different species may be white, gray, black, or brown.
Ø Down feathers are not waterproof, and chicks must remain out of the water until they acquire their juvenile plumage.
Ø Adult plumage is acquired at about 1 year.
v In all species, the coloration and markings of chicks separate them from adults. Scientists believe that the chicks’ coloration elicits parental behavior from the adults, and that adults do not perceive the young birds as competitors for mates or nesting sites.
v The striking coloration of emperor chicks may help to make the chicks more visible against the ice and snow, significant because emperors don’t have individual nest sites where the young can be found.
Care of the chicks:
Chicks require attentive parents for survival. Both parents feed the chick regurgitated food. Adults recognize and feed only their own chick. Parents are able to ID their chick by its distinctive call.
Male emperors exhibit a feature unique among penguins. If the chick hatches before the female returns, the male, despite his fasting, is able to produce and secrete a curdlike substance from his esophagus to feed the chick, allowing for survival and growth for up to 2 weeks.
Parents brood chicks/keep them warm by covering them with their brood patch.
In some species, partially grown chicks gather in groups called crèches. These groups provide some protection from predators and the elements.
Chick development: a chick depends on its parents for survival between hatching and the growth of its waterproof feathers. This may range from 7 weeks/Adelie to 13 months/kings. For most species, once a chick has replaced its juvenile down with waterproof feathers, it is able to enter the water and becomes independent of its parents.
Longevity and mortality:
v Longevity: the average life expectancy of penguins is ca 15-20 years, although some live considerably longer. High mortality occurs among the young.
ü Winter starvation may claim the lives of 50% of king chicks.
ü Emperor chicks may experience 90% mortality within the first year of life.
ü When mortality affects one chick in species producing 2 offspring of moderate size differences, it is usually the smaller chick that does not survive.
v Predators:
ü When in the water, penguins may be eaten by leopard seals, fur seals, sea lions, sharks, or killer whales.
ü On land, foxes, snakes, and introduced predators such as feral dogs, cats, and stoats/weasels prey on eggs and chicks.
ü Antarctic and subantarctic chicks are susceptible to predatory birds such as skuas, sheathbills, and giant petrels.
ü Gulls and ibises eat 40% of African penguin eggs.
ü Fairy penguins rely on burrows and a nocturnal lifestyle to avoid predators such as swamp harriers, peregrines, gulls, snakes, rats, and lizards.
v Human impact:
ü Indigenous peoples have hunted some species and taken eggs.
ü Mass exploitation occurred when early explorers, sealers, whalers, and fishermen turned to penguin colonies as sources of fresh meat and eggs. Sometimes, more than 300,000 eggs were taken in annual harvests from one African island. Explorers were known to kill and salt 3000 penguins in a day for voyage provisions. Penguins were easy prey because of their inability to fly and their seeming lack of fear of humans. Although egg collecting was banned in 1969, illegal harvesting continues today.
ü During much of the 19th and into the 20th century, penguin skins were used to make caps, slippers, and purses. Feathers were used for clothing decorations and as mattress stuffings.
ü The extraction of oil from penguins’ fat layers became economically important in the 1800s and early 1900s. Oil was used for lighting, tanning leather, and fuel. In the
ü Seabird guano has great commercial value as a nitrogen rich fertilizer. Although the Incas used seabird guano to improve their crops as far back as 500 B.C., they carefully managed the resource by extracting it at a slower rate than it was being produced. Guano became a major product of international trade in the 1800s and in the early 1900s. Guano deposits were in danger of being depleted. Guano harvesting is better managed today, but overexploitation of this commodity is a serious threat to the Humboldt penguin population, which relies on accumulated guano to dig burrows into rocky and soil-poor nesting areas.
ü In some places, such as islands in the southern
ü Human competition for food sources can affect penguin populations. Overfishing for anchovetta, the primary food source for the Humboldt penguins, has contributed to penguin population declines.
ü The introduction of predators has had devastating effects in some areas. Rats, dogs, pigs, and ferrets have been known to prey on chicks, eggs, and even adult penguins. Introduced herbivores, such as sheep and rabbits, cause serious deterioration of habitat.
ü Colonies of penguins have been affected by building activities and road construction. One colony of kings at Iles Crozet (a small group of islands in the
ü Trash in the ocean can affect seabirds. Penguins have been known to ingest plastic or become entangled in debris, causing injury and death.
ü Oil spills affect penguins. Oil fouls feathers, reducing waterproofing and insulating properties of their plumage, making the birds susceptible to hypothermia. Penguins also ingest the oil while trying to preen, which poisons them and causes internal organ damage.
ü Traces of DDT.dichlorodiphenyltrichloroethane and other pesticides have been found in the tissues of Adelie and chinstrap penguins. Scientists speculate that these pollutants were transported by ocean currents or other animals. Their appearance in Antarctic penguins is significant in that these toxic substances have now reached the pristine Antarctic.
ü Activity that may seem harmless, such as aircraft flying over penguin colonies, may cause panic and stampedes, resulting in injury and easy predation.
ü The population of ecotourism is increasing with cruise ships frequenting Antarctic waters. Enthusiastic sightseers must be careful not to interfere with normal penguin activity by staying back and keeping noise levels down.
ü Penguins may be indirectly affected by past hunting of whales. The increase of some penguin species over the last 30 years may be attributed to the greater availability of krill following the reduction of some Antarctic whale populations. However, the commercial value of krill may encourage large scale harvesting of this resource in south polar waters, which would impact penguins and other marine animals that rely upon krill as a food source.
El Nino: this ocean phenomenon, involving a change in wind and ocean current pattersn, which warms surface temperatures and reduces upwelling of nutrient rich waters, affects plankton, krill, and small fishes, which comprise the food supply of larger marine animals. Penguin species most affected are the Humboldt and Galapagos penguins.
ü The 1982-83 El Nino caused a 65% depletion of the Humboldt population off the coast of
ü Up to 77% of the Galapagos penguins was wiped out by the 1982-83 El Nino, leaving only 463 total birds. A slow recovery began in 1985. However, a further decline of 66% of the population occurred during the 1997-98 El Nino. The population once again appears to be in a recovery phase.
Conservation:
Legal protection: all 17 species are legally protected from hunting and egg collection. At least 3 species are considered at risk.
v The Antarctic Treaty was signed by 12 nations in 1959 and reauthorized in 1991 to protect
v The convention on International Trade in Endangered Species of Wild Fauna and Flora is an international treaty developed in 1973 to regulate trade in certain wildlife species, including penguins.
v The World Conservation
v The Endangered Species Act, 1973. Administered by the
Wildlife refuges:
v Protection of habitat began in the early 1900s.
v The Conservation Assessment and Management Plan seeks to evaluate the status of various animals and to determine conservation policies. In 2004, the 5th following the conference, a 2-day collaborative workshop sponsored by SeaWorld and the New England Aquarium reviewed the 2004 fact sheets, updated the 1998 listing for all species of penguins, and looked at penguin conservation priorities and future initiatives. International Penguin Conference was held;
v Zoological parks. Most people do not have the opportunity to observe penguins in the wild. The unique ability to observe and learn directly from live animals increases public awareness and appreciation of wildlife. Currently, the 3 Sea World parks maintain emperor, king, Adelie, gentoo, chinstrap, rockhopper, macaroni, Magellanic, and Humboldt penguin species. Each has successfully reproduced within the parks’ comprehensive breeding program.
v SW-BG Conservation Fund. Seeks to encourage sustainable solutions by supporting critical conservation initatives worldwide. Grants awards 2/year to selected projects that are science-based, solution driven, and community oriented. Accepts donations to support conservation projects in the
Species:
Emperor penguin: 44 inches tall; 60-90 pounds. Circumpolar on Antarctic continent within limits of pack ice. Feed on fishes and squids. Main predators are leopard seals, killer whales, and skuas. Ca 300,000 individuals.
King penguin: 37 inches tall; 30-35 pounds. Subantarctic islands and peninsulas, usually forage in ice free waters. Feed on squids and fishes. Predators leopard seals, skuas, giant petrels, gulls, sheathbills. CA 2,000,000 adults.
Adelie penguin: 18-24 inches tall; 8-10 pounds. Circumpolar on Antarctic continent within limits of pack ice. Feed primarily on krill, but also on squids and fishes. Leopard seals, skuas, and sheathbills major predators. 4,000,000-5,200,000 individuals.
Gentoo penguin: 24-30 inches tall; 12-14 pounds. Circumpolar in subantarctic and Antarctic waters, avoiding pack ice and continental coasts, feeding on krill and squid. Skuas, leopard seal, Antarctic fur seal,
Chinstrap penguin: 16-18 inches tall; 5-6 pounds. Subantarctic islands. Feed on fishes, squid, krill. Predators
Rockhopper penguin: 16-18 inches tall; 5-6 pounds; subantarctic islands, feeding on fishes, squid, krill. N.Z. fur seals and sea lions, Southern sea lions, skuas, gulls major predators. About 7,340,000 mature individuals.
Royal penguin: 26-30 inches tall; 12 pounds; Macquarie, Bishop, and
Erect crested penguin: 25 inches tall; 6-8 pounds; breed only on the Antipodes and
Macaroni penguin: 20-24 inches tall; 10 pounds; subantarctic islands in the
Fiordland crested penguin: 24 inches tall, 6-7 pounds; subantarctic islands and
Yellow eyed penguin: 30 inches tall; 3 pounds.
Magellanic penguin: 24-28 inches tall; 11 pounds. Falkland Islands and along the coasts of
African penguin: 24-28 inches tall; 7 pounds. South African waters, feeding mostly on anchovies, sardines, squids, crustaceans and other fishes. South African fur seals, southern sea lions, octopus, sharks, sacred ibis, gulls major predators. About 180,000 adults.
Fairy penguins: 16 inches tall; 2 pounds; southern
Humboldt penguin: 22-26 inches; 9 pounds; islands off western
Galapagos penguin: 21 inches tall; 5-6 pounds.
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