It’s too sweet to think of a pair of birds who mate for life, staying together even when they’re not raising chicks. However, this setup is sort of rare. Even birds thought to be monogamous such as song sparrows were found by ornithologists to “cheat.” Males sometimes wake up early in the morning to get a bit of side action, and not all the chicks a “socially monogamous” pair raise have the same biological father. Even pairs who are biologically monogamous may not give each other the time of day when the next breeding season comes around. So these birds, who mate for life, only have babies with that mate (most times) and only pick another mate when the first one disappears, are special. Check out these 10 birds that mate for life!
Some ornithologists believe that one reason for monogamy in birds is that their lifespans are so short that they don’t have time to court a new mate every breeding season. However, this isn’t true of the albatross, a seabird that spends most of its life gliding over the sea or resting on the waves and can live for over half a century. Maybe the albatross’s monogamy has to do with its courtship dance, which is long, complicated, and exhausting. Not only that, an albatross has to perform the ritual with many potential mates until they find “the one.” After that, the dance never has to be performed again and the birds are now mates for life!
#9: Black Vultures
Found in the northeastern United States and down into South America, the black vulture is the only member of the Coragyps genus and can be told from the turkey vulture not just by its black head but by its silhouette as it soars. The black vulture’s wings are straight across, while the turkey vultures are V-shaped. The black vulture is not only monogamous but prefers the company of its relatives and will fight unrelated vultures that try to join their flock.
#8: Macaroni Penguins
Macaroni penguins with their orange, yellow, or black V-shaped crests are found around Antarctica and north into Chile and the Falklands, and other islands. They come to islands in the southern Atlantic ocean in the fall to breed, and eventually, these islands are covered with millions of birds whose guano can be smelled miles away. Because there are more males than females, the hens are picky when it comes to their mates.
Males engage in elaborate courtship rituals to woo them and when they pair up they spend some time strengthening their bond through vocalizations, bowing, and preening each other. The females lay two eggs but only one tends to hatch, and both parents take care of the resulting chick. Though there are millions of these penguins, their conservation status is still listed as vulnerable. This is probably due to climate change and the overfishing of its prey, krill.
#7: Bald Eagles
Like other birds that mate for life, bald eagles indulge in elaborate courtship rituals, including aerial displays that involve the two locking talons, cartwheeling, and free-falling, only to separate just before they hit the ground. It seems a type of trust exercise! After mating, the pair find a sturdy tree and build a huge nest out of sticks that can be 13 feet deep, nine feet across, and weigh over a ton. Then, the female will lay two eggs, on average. The chick that hatches first sometimes kills the younger and weaker chick, but not always. If it’s well-fed, a bald eagle chick can gain six ounces a day. This makes it the fastest-growing chick of any bird in North America.
#6: Sandhill Cranes
Found in the northern United States up into Canada and across the Bering Strait into Siberia though it winters in Florida and the American southwest, this crane is famous for the displays that create a pair. Scientists have noticed at least five actions that make up these displays. They’re the upright wing stretch, vertical tosses and leaps, the bow, and the horizontal head pump. Once the cranes are mated, they use three actions to maintain their bond. They copulate, raise their bill, and call in unison. Besides pairs, sandhill cranes like to be around family members and even unrelated cranes who help in finding food and shelter.
#5: Barn Owls
This owl with its odd, heart-shaped facial disk and eerie dark eyes is the most widespread in the world and can be found in all the continents save Antarctica. Though they mate for life, mostly, barn owls don’t stay together throughout the year and only come together again during the breeding season. At other times, males and females have separate roosts.
Though their courtship displays aren’t as flashy as those of eagles, cranes, or albatrosses, they do perform aerial acrobatics while they screech. A person can tell the difference between males and females because his voice has a higher pitch, and hers is lower. She’s also bigger than her mate. The male also feeds the female, and mates with her after she’s reached the weight where she can successfully lay and incubate eggs.
#4: Love Birds
Of course, lovebirds have to be on this list. Their very name speaks of their monogamous character. Lovebirds aren’t one species of bird but describe species of parrots that belong to the Agapornis genus. Eight of the parrots are found on the continent of Africa while one, the grey-headed, is found in Madagascar. Their instinct to bond is so fierce that they will even bond with their human owner, and female lovebirds will lay eggs without mating, though the eggs are infertile. Lovebirds choose their life partners when they’re as young as two months old.
Watching lovebirds choose their mates is amusing. The males court the females carefully since a female who’s not interested can be aggressive. He’ll sidle up to her, and if she’s not receptive, he’ll switch to the other side. He’ll bob his head, and if she lets him, he’ll gently scratch hers. If they’re a couple, he’ll feed her. Both parents build the nest and care for the chicks.
#3: Atlantic Puffins
The Atlantic puffin fills the niche that the penguin would fill if most penguins lived north of the equator. Indeed, the puffin lives far north of the equator and is found in Greenland, Iceland, Labrador, Nova Scotia, Maine, and east to France. But unlike the penguin, the puffin can fly and spends much of its life over the open ocean. It only comes to land to breed in great colonies spread out over seaside cliffs.
While they’re at sea, puffins are solitary, but they find their mate during the breeding season. Some observers believe that the puffin isn’t as dedicated to its mate as it is to its former nesting site, which it uses over and over. The mates strengthen their bond by refurbishing the nest and by billing or rattling their colorful beaks together.
#2: Carolina Wrens
This aggressive little bird, South Carolina’s state bird, is probably an example of the benefits of monogamy to short-lived birds because it doesn’t live more than 10 years in the wild. The wrens’ monogamy might also be linked to their defense of their territory, for it is harder for a female to defend her territory without a mate, especially during the winter. Not only this, but the chicks also defend the family territory when they are old enough to fly. Still, the male puts on a show to attract a mate. He’ll fly circles around the female, hop, puff up his feathers, fan out his tail and offer her a bug or two.
#1: Trumpeter Swans
Despite their reputation, not all swans mate for life. But the beautiful trumpeter swan of northern North America does mate for life and like the lovebird, it will pick a mate when it’s too young to breed. Though they’re not ready to reproduce until they’re at least four years old, trumpeter swans can pair up when they’re less than two. Unlike the puffin, they stay together even when they’re not raising chicks and even when they are in the midst of a huge flock. To strengthen their bond, pairs raise and quiver their wings, bob their heads, and utter that famous trumpeting.
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