Geographic Range
Magellanic penguins live and breed in the Neotropical region along the southern coast
of South America. They are found from about 30°south in Chile to 40° north in Argentina,
and the Falkland Islands. Some populations on the Atlantic coast migrate north up
to the Tropic of Capricorn.
- Biogeographic Regions
- neotropical
Habitat
Magellanic penguins primarily inhabit temperate regions of South America, but during
the non-breeding season may follow oceanic currents northward into more tropical latitudes.
During the breeding season, Magellanic penguins nest on shoreline grassland habitats
that provide adequate, shrubby vegetative cover, but are near the ocean so parents
can easily forage. This species may also nest within burrows on cliff faces. When
not breeding, Magellanic penguins live pelagic lifestyle and spend nearly all of their
time off the southern coast of South America. Individuals typically travel anywhere
from 100 to 1,000 km off shore. While at sea, this species has been recorded to dive
to depths of up to 76.2 meters.
- Habitat Regions
- temperate
- terrestrial
- saltwater or marine
Physical Description
Magellanic penguins' weights vary with the season. They tend to weigh the most directly
prior to molt (which begins in March) since they are preparing to fast for the following
few weeks. Males have a mean weight of 4.7 kg and females weigh a mean of 4.0 kg.
The mean flipper length for males and females is 15.6 cm and 14.8 cm, respectively.
The average beak length is 5.8 cm for males and 5.4 cm for females. Males and females
have webbed feet that are, on average, 12.2 cm and 11.5 cm long, respectively. Adults
and juveniles both have black bills, black backs, and white fronts. Adults have a
symmetrical white band that originates at each eye, arches back on the sides of their
heads, and comes together above their necks. Adults also have two black bands underneath
their neck; juveniles only have one band. Juveniles display a range of white to dark
gray patches on their cheeks. Juveniles have two layers of down before they develop
their adult plumage.
- Other Physical Features
- endothermic
- homoiothermic
- bilateral symmetry
- Sexual Dimorphism
- sexes alike
- male larger
Reproduction
Magellanic penguins are a monogamous species that upholds their pair-bonds for many seasons. An unmated male attracts a mate first by calling, which is more accurately described as "braying" like a donkey. Once an interested female comes forward, the male will walk in a circle around her and eventually will rapidly pat her with his flippers. A breeding pair often performs mutual preening to uphold their pair-bond.
Male Magellanic penguins also fight each other for both nests and females. When males
fight before females have laid eggs, the larger male typically wins. These winners
are more likely to breed and thus have more chicks. The winners' nest sites tend to
be more covered and protected from the elements as well. When fighting occurs after
egg laying, the winner, regardless of size, is typically the owner of the nest that
he is trying to protect.
- Mating System
- monogamous
Magellanic penguins nest close to shore. They prefer to build their nests under a
bush, but will also dig burrows into substrate if necessary. They choose areas where
the substrate is composed of small particles such as silt and clay and low amounts
of sand. Magellanic penguins breed in dense colonies where nests may be only 123
to 253 cm apart. Adults will arrive at their breeding grounds in early September
and lay two eggs in late October. The average annual reproductive success is 0.52
chicks per nest. The clutch hatches asymmetrically, and the first hatched generally
is bigger and better able to obtain food from the parents. Thus, one chick typically
dies from starvation unless there is an overabundance of food or the colony size is
small. Eggs weigh 124.8 grams and are 7.5 cm long. The incubation period lasts for
40 to 42 days and the chick brooding period lasts from 24 to 29 days. The young fledge
at 40 to 70 days old, typically during January to the beginning of March. Fledglings
group together in creches and immediately take to the water, while adults remain on
shore for several weeks to molt. Juvenile Magellanic penguins do not reproduce until
4 years of age.
- Key Reproductive Features
- iteroparous
- seasonal breeding
- gonochoric/gonochoristic/dioecious (sexes separate)
- sexual
- oviparous
Both male and female penguins defend their nest, eggs, and young. Once the clutch
is laid, incubation duties are shared and initially each parent will perform a two-week
long shift. Parents switch more frequently as the incubation period progresses. When
the young hatch after 40 to 42 days, they are semi-altricial meaning they are downy,
immobile, and completely dependent on their parents for food and temperature regulation.
Parents continue to alternate incubating and foraging duties, and the young are fed
through regurgitation. The young are constantly cared for and brooded for 24 to 29
days, after which the parents spend extended periods of time foraging and will return
to the nest every 1 to 3 days. At 40 to 70 days old, the young fledge and immediately
take to the water in large groups, or creches. Fledgling penguins do not receive
further parental care, as the parents remain on shore to molt. Once the adults have
fledged, mixed groups of juvenile and adult penguins migrate north to the wintering
grounds.
- Parental Investment
- altricial
- male parental care
- female parental care
-
pre-fertilization
- provisioning
-
protecting
- male
- female
-
pre-hatching/birth
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
-
pre-weaning/fledging
-
provisioning
- male
- female
-
protecting
- male
- female
-
provisioning
Lifespan/Longevity
Magellanic penguins live for an average of 25 to 30 years in the wild. Juvenile penguins
suffer the highest mortality rate during their first pelagic migration, but annual
survival slowly increases as they age. Causes of mortality for both juveniles and
adults include predation, climatic variation, discarded human garbage, oil spills,
and commercial fishing.
Behavior
Like most penguins, Magellanic penguins are primarily pelagic and are specialized for foraging in the open ocean. Magellanic penguins are migratory birds that travel south to breed on the southern shores of South America and nearby oceanic islands. During the breeding season they are significantly more terrestrial, as they nest and care for their young on sandy shores or cliff faces. At the end of the breeding season, adults and juveniles migrate north and take on a pelagic lifestyle, capable of foraging up to 1,000 km off shore.
Although both male and female Magellanic penguins are known to fight in defense of their nests, most fights involve two males who fight in territorial disputes. These fights are common on the breeding grounds, where colonies of up to 200,000 individuals are densely crowded and pairs may nest within 200 cm of each other. When they are ready to leave the nest, fledgling penguins immediately take to the ocean in large groups or creches. Adults will later join them at sea, and all will travel northward together in cold ocean currents.
Magellanic penguins display behavioral adaptations to cope with warm weather. If they
get too hot, they can extend their flippers upward in order to increase the amount
of surface area exposed to a breeze.
- Key Behaviors
- natatorial
- diurnal
- motile
- migratory
- territorial
- colonial
Home Range
Specific territory size is currently unknown for Magellanic penguins. Individuals
do not defend a feeding territory in the open ocean, but both males and female vigorously
defend the immediate area surrounding their nests. The defended area fluctuates in
size depending on nesting densities, but may be as small as 3 square meters.
Communication and Perception
Magellanic penguins perform a variety of vocalizations and are able to discriminate between conspecific calls. Such calls include ecstatic display calls, mutual display calls, fight calls and contact calls. Males perform ecstatic display calls in the beginning of breeding season to attract a mate and during altercations with other males. These calls are described as "braying" for their similarity to the calls of donkeys. Both males and females use a mutual display call when they meet at their nest in the beginning of the breeding season and when they switch duties during incubation. Females respond more strongly to their mates' calls than to other male calls. The females stand up, look around and sometimes call back. Chicks can also discriminate between their parents' mutual calls and the mutual calls of another set of parents.
Mated pairs also use tactile and visual displays to communicate with each other and strengthen their bond. To show interest in a female, the male will walk circles around a potential mate and then pat her rapidly with his flippers. A mated pair will remain together for many years, and often perform mutual preening to uphold their bond.
Studies have suggested that penguins, in general, rely heavily upon their sense of sight to obtain food and navigate underwater. It has been suggested that these birds can see at least a portion of the ultraviolet spectrum. Study of the retina has also revealed that it lacks the ability to perceive the color red, and that they are very adept at perceiving blue or green spectra. This likely is connected to the fact that in the deep ocean, there is an abundance of blue and green coloration while red is rather rare. It has also been suggested that penguins' eyes are specially adapted to aquatic environments, as they share similar sensitivities with the eyes of fish.
Like most birds, Magellanic penguins perceive their environments through visual, tactile,
auditory and chemical stimuli.
Food Habits
Magellanic penguins are piscivores. While their basic diet consists mainly of pelagic
fish, their particular choice of prey varies on where they reside. Penguins that inhabit
northern colonies, such as San Lorenzo, Punca Clara, Punta Loberia, feed primarily
on
anchovies
. In the southern colonies of Monte Leon and Punta Dungeness, penguins prey on squid
(
Loligo
and
Illex
species),
sprats
and
hagfish
. They can dive more than 76.2 meters while hunting.
- Animal Foods
- fish
- mollusks
Predation
Penguin eggs and young chicks are prime targets for
kelp gulls
,
lesser grisons
and
large hairy armadillos
. While on land,
red foxes
,
gray foxes
,
pampas cats
and
pumas
prey on older penguin chicks, juveniles, and adults. Sea dwelling predators, including
giant petrels
,
South American sea lions
and
orcas
, feed on fledglings, juveniles, and adults.
Ecosystem Roles
At all life stages, Magellenic penguins are a valuable food source for various terrestrial
and aquatic animals. As predators themselves, Magellanic penguins keep local populations
of small fish and squid balanced.
Economic Importance for Humans: Positive
During their breeding season, magellanic penguins are popular tourist attractions.
Over 100,000 people visit their nesting grounds at Punta Tombo each year. For a few
years after 1982, this species became the target of human exploitation for their meat
and skins, which were used to make gloves.
- Positive Impacts
- ecotourism
Economic Importance for Humans: Negative
There are no known adverse effects of
Spheniscus magellanicus
on humans.
Conservation Status
When last assessed in 2010, the IUCN Red List categorized Magellanic penguins as near
threatened. While an overall moderately rapid decrease is apparent, some smaller colonies
of penguins have grown. During their annual migrations, penguins would often drift
into shipping lanes and get oiled. However, changes to the Chubut provisional law
moved the designated lanes to reduce oiling incidents. Magellanic penguins are also
unintentionally caught in fishing nets and die as a result. Through commercial fishing
humans are depleting populations of small fish which are a main component of Magellanic
penguins' diets. The IUCN has proposed reducing by-catch of an anchovy fishery in
Argentina and monitoring the effects on a penguin population in Punta Tombo as a possible
solution.
Additional Links
Contributors
Victoria LaMarre (author), The College of New Jersey, Matthew Wund (editor), The College of New Jersey, Rachelle Sterling (editor), Special Projects.
- Neotropical
-
living in the southern part of the New World. In other words, Central and South America.
- native range
-
the area in which the animal is naturally found, the region in which it is endemic.
- temperate
-
that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).
- terrestrial
-
Living on the ground.
- saltwater or marine
-
mainly lives in oceans, seas, or other bodies of salt water.
- pelagic
-
An aquatic biome consisting of the open ocean, far from land, does not include sea bottom (benthic zone).
- coastal
-
the nearshore aquatic habitats near a coast, or shoreline.
- endothermic
-
animals that use metabolically generated heat to regulate body temperature independently of ambient temperature. Endothermy is a synapomorphy of the Mammalia, although it may have arisen in a (now extinct) synapsid ancestor; the fossil record does not distinguish these possibilities. Convergent in birds.
- bilateral symmetry
-
having body symmetry such that the animal can be divided in one plane into two mirror-image halves. Animals with bilateral symmetry have dorsal and ventral sides, as well as anterior and posterior ends. Synapomorphy of the Bilateria.
- monogamous
-
Having one mate at a time.
- iteroparous
-
offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).
- seasonal breeding
-
breeding is confined to a particular season
- sexual
-
reproduction that includes combining the genetic contribution of two individuals, a male and a female
- oviparous
-
reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.
- altricial
-
young are born in a relatively underdeveloped state; they are unable to feed or care for themselves or locomote independently for a period of time after birth/hatching. In birds, naked and helpless after hatching.
- male parental care
-
parental care is carried out by males
- female parental care
-
parental care is carried out by females
- natatorial
-
specialized for swimming
- diurnal
-
- active during the day, 2. lasting for one day.
- motile
-
having the capacity to move from one place to another.
- migratory
-
makes seasonal movements between breeding and wintering grounds
- territorial
-
defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement
- colonial
-
used loosely to describe any group of organisms living together or in close proximity to each other - for example nesting shorebirds that live in large colonies. More specifically refers to a group of organisms in which members act as specialized subunits (a continuous, modular society) - as in clonal organisms.
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- visual
-
uses sight to communicate
- tactile
-
uses touch to communicate
- acoustic
-
uses sound to communicate
- chemical
-
uses smells or other chemicals to communicate
- ecotourism
-
humans benefit economically by promoting tourism that focuses on the appreciation of natural areas or animals. Ecotourism implies that there are existing programs that profit from the appreciation of natural areas or animals.
- carnivore
-
an animal that mainly eats meat
- piscivore
-
an animal that mainly eats fish
References
Boersma, D. 2009. "Magellanic Penguin" (On-line). Penguin Sentinenels. Accessed February 24, 2011 at http://mesh.biology.washington.edu/penguinProject/Magellanic .
Boersma, P., D. Stokes, P. Yorio. 1990. Penguin Biology: Reproductive variability and historical change of Magellanic penguins (Spheniscus magellanicus) at Punta Tombo, Argentina . San Diego: Academic Press.
Boersma, P., D. Stokes. 1995. The penguins (Bird families of the world): Conservation: threats to penguin populations . New York: Oxford University Press.
Borboroglu, P., P. Yorio, P. Boresma, H. Del Valle, M. Bertellotti. 2002. Habitat use and breeding distribution of magellanic penguins in Northern San Jorge Gulf, Pantagonia, Argentina. The Auk , 119/1: 233-239. Accessed April 10, 2011 at http://www.jstor.org/pss/4090029 .
Boresma, P. 2008. Penguins as marine sentinels. BioScience , 58/7: 597-607. Accessed April 10, 2011 at http://www.jstor.org/stable/10.1641/B580707 .
Clark, J., P. Boersma, D. Olmsted. 2006. Name that tune: call discrimination and individual recognition in Magellanic penguins. Animal Behvaiour , 72: 1114-1148. Accessed February 24, 2011 at http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6W9W-4KXVD2D-1&_user=1086025&_coverDate=11%2F30%2F2006&_rdoc=1&_fmt=high&_orig=search&_origin=search&_sort=d&_docanchor=&view=c&_acct=C000051441&_version=1&_urlVersion=0&_userid=1086025&md5=bea9b388a03557e6644833079c2f41ac&searchtype=a .
Laurenti, S., H. Gallelli. 1999. Feeding preferences of the Magellanic penguin over its breeding range in Argentina. Waterbirds: The International Journal of Waterbird Biology , 22: 104-110. Accessed February 23, 2011 at http://www.jstor.org/pss/1521999 .
Martella, M. 2001. "Winning and losing: causes for variability in outcome of fights in male Magellanic penguins (Spheniscus magellanicus)" (On-line). Oxford Journals: Behavioral Ecology. Accessed March 19, 2011 at http://beheco.oxfordjournals.org/content/13/4/462.full .
Martin, G. 1985. Through a penguin's eye. New Scientist , 105/1447: 29-31.
Müller-Schwarze, D. 1984. The behavior of penguins: adapted to ice and tropics . Albany, NY: SUNY Press.
Peters, G., M. Kierspel. 1995. Foragine areas of Magellanic penguins Spheniscus magellanicus breeding at San Lorenzo, Argentina, during the incubation period. Marine Ecology Progress Series , 129: 1-6. Accessed February 23, 2011 at http://www.int-res.com/articles/meps/129/m129p001.pdf .
Reid, W., P. Boersma. 1990. Parental quality and selection on egg size in the Magellanic penguin. Evolution , 44: 1780-1786. Accessed February 23, 2011 at http://www.jstor.org/stable/2409506 .
Stokes, D., P. Boersma. 1991. Effects of substrate on the distribution of Magellanic Penguin Burrows. The Auk , 108: 923-933. Accessed February 24, 2011 at http://www.jstor.org/pss/4088322 .
Stokes, D., P. Boersma. 1998. Nest-site characteristics and reproductive success in Magellanic penguins (Spheniscus magellanicus). The Auk , 115: 34-49. Accessed February 23, 2011 at http://www.jstor.org/pss/4089109 .
Walker, B., P. Boersma, J. Wingfield. 2005. Physiological and behavioral differences in Magellanic penguin chicks in undisturbed and tourist-visited locations of a colony. Conservation Biology , 19: 1571-1577. Accessed February 23, 2011 at http://www.jstor.org/stable/3591125?&Search=yes&searchText=magellanicus&searchText=Spheniscus&list=hide&searchUri=%2Faction%2FdoBasicSearch%3FQuery%3DSpheniscus%2Bmagellanicus%26acc%3Don%26wc%3Don&prevSearch=&item=3&ttl=59&returnArticleService=showFullText .
Williams, T. 1995. The penguins: Spheniscidae . New York: Oxford University Press.
Yorio, P., P. Boersma. 1994. Causes of nest desertion during incubation in the Magellanic penguin (Spheniscus magellanicus). The Condor , 6: 1076-1083. Accessed February 23, 2011 at http://www.jstor.org/pss/1369116 .
Yorio, P., P. Boersma. 1994. Consequences of nest desertion and inattendance for Magellanic Penguin hatching success. The Auk , 111: 215-218. Accessed March 23, 2011 at http://www.jstor.org/pss/4088528 .
2011. "Magellanic Penguin" (On-line). Wildlife Conservation Society. Accessed February 24, 2011 at http://www.wcs.org/saving-wildlife/birds/magellanic-penguin.aspx .
Wildlife Conservation Society. 2011. "Magellanic Penguin" (On-line). Wildlife Conservation Society: Bronx Zoo. Accessed February 24, 2011 at http://www.bronxzoo.com/animals-and-exhibits/animals/birds/magellanic-penguin.aspx .
2000. Nesting density and reproductive success in a colonial seabird, the Magellanic Penguin. Ecological Society of America , 81/10: 2878-2891. Accessed February 23, 2011 at http://www.jstor.org/stable/177348?&Search=yes&searchText=magellanicus&searchText=Spheniscus&list=hide&searchUri=%2Faction%2FdoBasicSearch%3FQuery%3DSpheniscus%2Bmagellanicus%26acc%3Don%26wc%3Don&prevSearch=&item=5&ttl=59&returnArticleService=showFullText .
2011. "Species factsheet: Spheniscus magellanicus" (On-line). BirdLife International. Accessed March 19, 2011 at http://www.birdlife.org .
2010. "Spheniscus magellanicus" (On-line). IUCN Red List. Accessed February 24, 2011 at http://www.iucnredlist.org/apps/redlist/details/144812/0 .