Penguins are a fascinating group of birds. Each of the eighteen species in the Spheniscidae family is flightless, and they are far more at home in the water than on the land. With the exception of the Galapagos Penguin, each occurs far south of the equator.
Most Penguins breed in relatively inaccessible areas, which makes it difficult to observe their breeding habits. So how do Penguins find partners? Do they mate for life?
The breeding strategy of each penguin species varies somewhat, but all species form partnerships that can last for more than a year. In some cases, they could mate for life, but this is certainly not always the case. In fact, partner fidelity can be as high as 89 percent in some species but as low as 15 percent in others.
All Penguins are monogamous, however, and exhibit biparental care, which means both mother and father work together to raise their one or two chicks.
Fidelity rate ranges significantly across Penguin species - a pair of Magellanic Penguins
The behavior of each penguin species has been developed over countless generations to maximize their breeding success. In many cases, the nest site ties a pair together because they can reunite at a fixed point and time each breeding season.
Penguins that use the same nest site tend to show high mate fidelity.
In this article, we cover the pairing and mating habits of Penguins. Their behaviors range from endearing to downright disgusting.
Penguins are relatively long-lived birds, and many species can live for over twenty years. Adelie Penguins and Royal Penguins are usually only ready to breed at eight years old, although Gentoo Penguins can reach sexual maturity after just two years. Their longevity makes life-long studies difficult.
Many penguin species form partnerships that last two or more consecutive years, but Penguins are not very faithful partners.
Continue reading to learn about the fidelity rates of some well-known Penguins.
The Little Penguin (Eudyptula minor) is the smallest species in the world. These Australian seabirds show high fidelity to their mate and the burrow where they make their nests. The pair typically reunites, although they may divorce, especially after an unsuccessful breeding season.
Little Penguins generally have a high fidelity rate between breeding pairs
Mate fidelity varies pretty dramatically among breeding pairs of the fast-swimming Gentoo Penguin (Pygoscelis papua). They will pair up with the same partner anywhere between zero and 89% of the time, although they are far more faithful to their nest site. Male Gentoo Penguins re-use the same nest site 89% to 100% of the time.
Gentoo Penguin fidelity has huge variation
Emperors (Aptenodytes forsteri) are the least faithful of the penguin species, but they have a good reason. These massive seabirds breed in the harsh Antarctic winter, incubating their egg on their feet rather than in a nest.
They breed in huge colonies on desolate ice sheets, making it tough to find the same partner each year. Nevertheless, old flames do manage to find each other sometimes, and they are estimated to reunite about 15% of the time.
Fidelity of other notable species:
Emperor Penguins are the least faithful species of Penguin
Penguins use a variety of different displays to attract a mate. These include their own physical qualities, the sound of their voice, and the quality of their nest site.
Keep reading to learn more about penguin mate selection.
At first glance, most Penguins look like they have no color except black and white. In fact, most species have some pretty bright colors around the head and bill that can be important for mate selection.
Male and female King Penguins select each other based on the amount of UV light reflected off their beaks and the colorful auricular patch over their ears.
Female Penguins can judge the quality of a potential mate by the kind of nest site he has because a comfortable and sheltered nest provides a much better chance of successfully raising their chicks. Male Penguins display near their nest site, advertising themselves and their nest.
Male and female King Penguins select each other based on the amount of UV light reflected off their beaks and the colorful auricular patch over their ears
Male Penguins use songs to attract potential mates. They perform a delightful display known as the ecstatic display call. The sounds they produce don't sound like music to our ears, but other Penguins seem to like them.
Penguins tend to spread their wings and point their beaks up at the sky while calling, but some birds also swing their heads from side to side or look down at their feet.
Male Penguins also use these calls to keep other males at bay, but males and females may perform this display in synchrony once they have paired up. This courtship ritual strengthens their mutual bond.
Penguins are known to have a pretty discerning ear. Researchers believe that Female Adélie Penguins can tell how much fat a male has by the quality of his voice. High body fat indicates his fitness since the birds will fast for as long as three weeks while incubating the eggs.
An Emperor Penguin pair in courtship displays and behaviors
Penguins do not rush their courtship, and this stage can last as long as six weeks in the case of breeding Emperor Penguins. Gentoo Penguins court each other for about a month.
During this time, the pair will display to each other and make frequent visits to stone collection sites each evening after returning from the day's fishing trip.
All Penguins nest in colonies, and finding a partner in the large and chaotic King Penguin breeding rookery presents its own unique challenges.
These colorful Penguins will move to the colony’s edge when seeking a partner. Here they display to each other, moving in together when they have found a mate.
You may be wondering how these birds find each other in the crowd, especially when there’s no nest site. King and Emperor Penguins identify each other by sound. Each individual can produce a unique sound using the two branches of their syrinx- the bird version of a voicebox.
A pair of Gentoo Penguins during a courtship display
The male Gentoo Penguin is known to collect a stone and drop it at the feet of a potential mate. If she is suitably impressed with this practical gift, the pair may go on to build a nest out of pebbles and softer materials like moss and grass.
Male Gentoo Penguin offering pebble to partner
Penguins breed once a year. They will mate after the pair have reunited at the nest site, although there is some evidence that they might even copulate out at sea.
In established penguin pairs, the male is usually the first to arrive back at the nest site in the breeding season. Female Chinstrap Penguins (Pygoscelis antarcticus), for example, return five days later on average.
Despite being monogamous, female Penguins may have as many as three partners, and males might also visit a second female. Some Penguins are known to mate with partners of the same sex, and others have even been seen attempting to mate with deceased birds around the colony.
Penguins are not always the faithful birds we make them out to be!
Love is in the air - breeding pair of Chinstrap Penguins
Most Penguins will pair up with the same partner each year, especially if they have been successful at raising chicks in the last season. If their mate should perish and fail to return to the nest site, however, the newly single bird will look for a replacement partner.
We do not know for sure if Penguins mourn the loss of a mate or if they are even capable of this kind of emotion. These birds have well-developed brains, however, so science may well uncover more complex emotional responses.
In fact, the Emperor Penguin has the largest bird brain in the world, weighing in at a (relatively) impressive 1.5 ounces (44g).
It's currently unknown if Penguins mourn the loss of their mate
Penguins are known to engage in many unsavory acts, but they do not usually mate with their siblings. This behavior is relatively rare in nature because it has terrible consequences for genetic diversity. In the confines of captivity, however, it is quite possible.
Penguins nest in colonies, and some species form crèches where the young birds get together for warmth and safety. Emperor Penguins are only independent at up to 13 months old, which is very long by bird standards. Such a long ‘family’ period means these birds can only breed twice every three years.
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