The Northern Cardinal is perhaps the most well-known and well-loved bird in the central and eastern United States. With their bright red plumage, male Northern Cardinals are easy to spot and admire. Because of their commonality and beauty, they may even be a “gateway bird” into the birding world.
While the female lacks the bright red feathers of the male, she is lovely with her striking red beak and soft tan plumage. As soon as you spot either the male or female red cardinal, you’ll soon see the other nearby.
No matter the season, red cardinal pairs stick together. This is yet another quality that makes cardinal birds so endearing. But are they truly as bonded as they seem? Do cardinal birds mate for life?
Read on to learn whether or not these beloved birds are as loyal and steadfast as they appear. And, if you’ve ever seen red cardinals “kissing,” continue reading to learn about their fascinating courtship and nesting behaviors.
So, Do Cardinal Birds Mate For Life?
Yes and no – some cardinal birds mate for life while others do not. According to The Cornell Lab of Ornithology, about 20% of cardinal pairs split by the following breeding season.
There are various reasons why some cardinal birds mate for life and others don’t. Some reasons are known while some are unknown. For instance, if nesting was unsuccessful, for whatever reason, cardinal pairs may split to find other mates.
Cardinals will also find new mates if the other one dies, and they don’t hesitate to pair up with another mate quickly.
‘Cheating’ Cardinals
While most cardinal breeding pairs are loyal, a research study found that some will discreetly “cheat” on their mate. Because of how inconspicuous female red cardinals are, the biologists couldn’t visually confirm what they call extra-pair copulations (EPCs). However, they found that about 13% of fledglings in their field study had biological traits that did not match the male cardinal in a breeding pair.
EPCs are not uncommon, even in socially monogamous birds such as red cardinals. Birds will have extra-pair copulations to improve overall fledgling success, especially when predation or nest failure is high.
That said, EPCs are relatively low in cardinals compared to other bird species. This is perhaps due to the male Northern Cardinal aggressively defending his territory and mate.
Interestingly, in two of the three cardinal nests with confirmed EPCs, the male was more absent from the female than in other breeding pairs. So, it’s likely that the closer the red cardinal stays to the female, the less likely it is for EPCs to occur.
Due to their elusive nature, the study couldn’t confirm female Northern Cardinal responsiveness to EPCs from trespassing males. The research biologists believe females are likely to avoid it in most cases because of how much they depend on their mate to help raise the young.
Despite the 20% chance of pair separation and EPCs, it’s generally believed that cardinal birds form lasting bonds with their mate and will stick together until death do them part. Northern Cardinals will even stay close to their mate during the winter, whether or not they join with a mixed winter flock.
Courtship
In early spring, red cardinals perform courtship displays to form new breeding pairs or deepen current bonds. Their courtship is sweet, gentle, and straight out of a bird romance novel. The male and female sing softly to each other with heads held high while swaying back and forth.
The male red cardinal will feed the female to show his ability to care for her and the fledglings. I’ve witnessed this firsthand at my birdfeeder.
The female waited on a nearby branch while the male gathered seed in his beak. He flew back to the female and ever so gently fed her the seed. They appeared to be “kissing.” It was perhaps the sweetest bonding moment I’ve witnessed between two birds (yes, I’m humanizing their romance because why not?).
Besides active courtship displays between the sexes, the male will sing to establish his territory. Both male and female Northern Cardinals will aggressively defend their nesting territory by dive-bombing intruders.
Nesting
The male and female cardinal will search out nesting sites, though the female tends to lead the search. They will carry nesting materials in their beak and communicate back and forth while assessing potential nest sites.
The female red cardinal chooses the nest site and builds the cup nest. The male will help by bringing her nesting material. The nests are usually in dense foliage or shrubs, hidden out of view. Northern Cardinal nests consist of an outer twig layer followed by a few inner layers of leaves, grapevine bark, rootlets, stems, pine needles, and grass.
Once the nest is built after about 3-9 days, she will lay 2-5 eggs. Eggs are white to grayish-white or greenish-white with light grey or brown speckles. The eggs hatch after an incubation period of 11-13 days.
During incubation, the male red cardinal will bring food to the female who does most, if not all, of the incubation. While sitting on her nest, the female will sing.
Cornell Lab of Ornithology says the female may do this to, “give the male information about when to bring food to the nest.” This is a rare and interesting fact about female cardinals, as many North American female songbirds don’t sing, much less while sitting on the nest.
The eggs hatch after an incubation period of 11-13 days. Both male and female Northern Cardinals feed young.
At this point, the male will mostly feed the fledglings while the female starts building the nest for the second brood. Cardinals usually have two or three broods but will not use the same nest twice.
Fledglings leave the nest after about 9-11 days.
Final Thoughts: Do Cardinal Birds Mate For Life?
So, do cardinal birds mate for life? While the answer isn’t as straightforward as it seems, there’s no doubt that most Northern Cardinals form special, long-term bonds. Coupled with their adorable (and fierce) courtship behavior, the red cardinal should be the romance icon of the birding world.
Red cardinals display both tenderness and protectiveness towards each other. They look out for each other and share parental duties. As such, cardinals may just be an exemplary example of partnership (besides the EPCs of course, but we all have relationship challenges from time to time).
