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Barn owl - Barn owls are often monogamous, sticking with the same mate until death do them part.

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Barn owl - About a month before the female lays her eggs, the male keeps her supplied with food.

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Red wolf - Red wolves are usually faithful to their mates and breed once a year.

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Red wolf - A red wolf family or pack will often consist of an alpha male and female, plus their offspring.

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Atlantic puffin - When Atlantic puffins partner up, they partner up for good.

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Atlantic puffin - Each season, they return to the same burrow, share the chores of egg incubating and parenting, and rub their beaks together in the cutest of ways.

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Seahorse - Most seahorses are monogamous, and some species tend to mate for life.

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Seahorse - The way they split parenting duties is unusual in that male seahorses will carry the unborn young in a pouch.

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Bald eagle - Bald eagles are monogamous once coupled off, and will stay together for life unless one member of the couple dies.

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Bald eagle - During courtship they engage in a ritual called a Cartwheel Display, during which the pair locks talons and somersaults through the air, breaking apart moments before they would hit the ground.

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French Angelfish - These fish aren't just monogamous... they're rarely apart.

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French Angelfish - They live, travel, hunt, and even defend their territory in pairs.

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Black vulture - Black vultures exhibit legendary monogamy. Pairs will stay together year-round, sharing parenting duties.

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Black vulture - Black vulture society discourages nonmonogamy... they have actually been known to attack those who are caught straying from their partners.

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Mute swan - These swans, introduced to North America from Europe, tend to stay together for life. 

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Mute swan - However, according to the Audubon Society, some couples do split up, and the swans tend to find new partners when their original partner dies.

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Prairie vole - Prairie voles only live for a year or two, but they spend their short lives with one partner.

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Prairie vole - Together, they build a nest, raise their young, groom each other, find the resources they need, and breed as much as possible.

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Wandering albatross - Despite the name, the affections of these birds don't wander from their mates. They couple up for life, breeding every two years.

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Wandering albatross - When the female lays her eggs, the couple takes turns incubating. When they hatch, the two will switch off between hunting and staying with the chick.

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Termite - Many species of termites have a monogamous king and queen who together breed the entire colony.

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Termite - The queen constantly produces offspring, which includes workers, soldiers, and once a year, breeders, which fly away to start their own colonies.

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Sandhill crane - Sandhill cranes are monogamous until a mate dies, at which point they'll seek out a new partner.

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Sandhill crane - Mates will practice "unison calling," where the female squawks twice and the male answers with a single call, to reinforce their bond.

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Mourning dove - Mourning doves mate for life, but while they have a lifespan of 7-10 years, they're heavily hunted and mates will often have to find a replacement due to the untimely demise of their partner.

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Mourning dove - Even their eggs are in pairs... mourning doves tend to lay just two at a time.

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Gray wolf - Like other wolves, gray wolves are mostly monogamous and stay with their partners for the rest of their lives.

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Gray wolf - Typically the pair will act as the head of a pack that includes their offspring.

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Beaver - Some say beavers are monogamous and mate for life, but it seems that it's the European beavers that are the faithful ones, while North American beavers "cheat."

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Beaver -

Regardless, North American beavers definitely partner up, through they may see other partners from time to time.

See also: The secret life of bats

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