Gentoo Penguin – Pygoscelis papua
Pygoscelis Genus – Brush-tailed Penguins
Height: 28-31 in.
Weight: 10.25-14.25 lb.
Two subspecies. Pygoscelis papua papua and the smaller Pygoscelis papua ellsworthii.
Life expectancy in the wild: 10-15 years.
Approximated Population: 950,000
Population tendency: Decreasing
IUCN Conservation Status: NT
Appearance
It is the largest species of its genus. The gentoo penguin has the distinctive black and white plumage, which turns brown in some areas due to their age. Their main feature is the white spot that is born in the bottom of both eyes and joins on the head.
Gentoo penguins’ legs are light orange while their beak is bright orange on the sides with a black line on the top and a long, straight and thick shape. About 70 feathers cover every square inch of their body, and they keep them with the proper body temperature. Their long tails have 14 to 18 feathers of about 5.9 in long. Hatchlings are visibly different; their feathers are gray and white and initially they do not have the distinctive white spot on their head that adults have.
Gentoo Penguin – Pygoscelis papua
Where do they live?
They have a circumpolar distribution, but some specific areas contain most of their population.
Gentoo penguins colonies are in the South Georgia, and the South Sandwich Islands, the Falkland Islands, the Crozet Islands, the Kerguelen Island, the Heard Islands, the South Orkney Islands, the Macquarie Island and some single individuals sometimes reach Australia, New Zealand, and South Africa.
Their habitat landscape varies according to the geographical location. In some places, icebergs and snow-covered areas, but in some other regions green pastures, rocky shores, and less cold waters constitute their environment.
Skills and Behavior
Gentoo penguins live most of their life in the same place where they breed.
These penguins are very social, and they usually do not show aggression among themselves or with other species of penguins, except when protecting their nests or eggs.
They are opportunistic hunters that keep in groups ranging from 20 to 150 members, and they hunt together to a maximum depth of 558 feet to find food.
Provided with excellent eyesight underwater, they can recognize colors like purple, blue or green, but once on the ground, their vision is not as good.
They use three different types of vocalizations:
CONTACT VOCALIZATIONS
They use this kind of sounds for recognition between partners or between parents and their offspring.
COURTSHIP VOCALIZATIONS
They produce these loud sounds during several days to courtship their partner.
WARNING VOCALIZATIONS
They use these sounds in dangerous situations. They are similar to a whistle that is followed by sudden head movements.
Molting
The pre-molting and molting periods happen in different months, but this changes according to their geographical location. The pre-molting may take from 20 to 40 days in some areas, while in others, it lasts twice as much. Molting takes approximately 25 days, and it happens between December and March when they lose between 40 and 55% of their body mass.
What do they eat?
Crustaceans, mainly Antarctic krill, make up most of the diet of the southern colonies while those living in northern areas prefer to feed on fish and cephalopods. They are efficient hunters who prefer staying in shallow or not so deep waters.
Gentoo penguin chick.
Reproduction
Sexual Maturity: 2 to 3 years.
Incubation period: From 34 to 36 days.
Normal clutch: Two eggs
Some couples stay together for life, but “divorces” also happen when the female chooses a new partner. The separation percentage is below 20%.
Some couples stay together for life, but “divorces” also happen.
A female selects a male based on his behavior. Therefore, he should impress the prospect by showing the place he chose to build the nest. If she is convinced, they mutually touch their beaks and show reverence by tilting their body.
Gentoo penguins build nests with several materials like pebbles, molted feathers, branches, and vegetation. Both are responsible for incubating the eggs and stop feeding the chicks two weeks after they have entered the water for the first time.
In their first trip to the ocean, both father and mother teach their chicks hunting and survival techniques, something amazing.
Threats
Skuas, and other carnivorous and opportunistic birds are natural enemies of the chicks and eggs. Adults, who inhabit areas close to the Antarctic, flee from predators such as leopard seals, killer whales, and sea lions.
Due to their proximity with humans in some areas, the collection of eggs has caused a decline in population. Oil exploration in the Falklands and tourism disturbance are also factors that disrupt their environment.
Gentoo penguin range map
Sources:
Salomon, David. Penguin-pedia, photographs and facts from one man’s search for the penguins pf the world. Brown Books. 2011.
Lynch, Wayne. Penguins of the world. Firefly. 2007.
http://www.falklandsconservation.com/wildlife/penguins/gentoo
http://www.iucnredlist.org/details/22697755/0
http://www.arkive.org/gentoo-penguin/pygoscelis-papua/
http://www.antarctica.gov.au/about-antarctica/wildlife/animals/penguins/gentoo-penguins
BioExpedition Publishing © 2017.
