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What percentage or birds that pair for life . . . (1 Viewer)


New member
United Kingdom
Hello forum,

Hi I just wanted to ask one question I can't find the answer to anywhere else and thought you guys might know the answer.

What percentage of (wild) birds of any given species that pair up for life - like essentially monogamous birds - do not find a mate?

I'm really wondering if humans are pairing up less than you'd expect for a less intelligent species. If all but a very few birds of whatever species find and stay with a mate then perhaps it's our intelligence that makes us picky, prone to communication (and with it arguments), mental and personality problems that are just not a thing with birds.
Are all the complications that go with the higher intelligence we have causing a higher percentage of us to stay un-paired up?

Thanks for any thoughts, especially if you can tell me the answer to the basic birds pairing up question.

Or any other animals that pair up.

Thanks again,

Hi, Pete. Welcome to the forum on behalf of the staff and moderators. I think you will find us a friendly and helpful group. And I have absolutely no idea to the answer to your question. I don’t know if it has ever been studied or thought about. Birds do have ways of mates and vying for mates. The % of birds that don’t ever find a mate has never even crossed my mind.
Welcome to Birdforum. I hope you enjoy your visits.

Interesting questions.
Most birds are seasonally monogamous, one male will pair with one female for that breeding season. Next year those two birds, if they survive, will pair with different partners. This is very different from what we would call monogamy in humans.

In a few bird species, mostly large long-lived birds, individuals will pair with the same partner each year. But if one of the pair dies then they will readily pair with another mate.

However most of the research into bird pairing predates modern DNA sequencing techniques. More recent research using DNA has found many cases where the the male involved in brood rearing is not the biological parent, even in multi-year paired birds.

A difficult part of answering your question is that it can be tricky to know whether an observed pair of birds is actually entirely monogamous. Without banding both of them and watching, it's hard to know if, say, a specific female is entertaining the attentions of a male other than the one she's built a nest with, and about the only way to check for certain is to run DNA tests on the chicks as compared to the adults. So it's hard to know whether a given species is monogamous at all, or if they just tend to appear that way. Some studies have shown that quite a lot of the nests of seemingly monogamous species contain genes from multiple males- never mind the species that don't bother with monogamy at all, doing things like building harems or raising babies alone.

You have to remember that the ultimate goal of an animal is to perpetuate its species, and, ideally, its specific genes. If being involved in more than one nest worth of eggs, or having more than one male worth of eggs in the nest, is useful, they'll do it. And the only reason their mate might object is out of a desire to put all the energy into raising its own babies, not because they have the same concept of betrayal that we do.

Also, birds are not people. I don't think you'll find the answers to society's woes in bird behavior.

(Well- you might find one or two hints, in social birds artificially kept apart. Parrots, for example, suffer when not kept in the large social groups they'd have in the wild. A parrot with a mate suffers less, but is still more stressed than a parrot in the appropriate social group, mated or not. It's not good for people to be isolated, not least because it builds a tendency for people to try to rely entirely on their significant other for all their social and emotional needs, which is just not sustainable.)
Thanks for your welcomes and replies.

So basically this, as with so much in life, is not as straight forward as a person might like it to be.


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