All About Birds Blog

Why So Red, Mr. Cardinal? NestWatch Explains

By on Tuesday, March 5th, 2013 - 65 Comments

Northern Cardinal by Daniel Behm via Birdshare

By Jason Martin and Robyn Bailey

In many parts of North America, handsome male Northern Cardinals are already singing to attract mates. A bird so visible in the winter landscape begs the question, “How does a flame-red bird that nests close to the ground manage to be so common?”

Many people puzzle over how this conspicuous species can be so successful, despite its low rate of nesting success. Typically, fewer than 40 percent of nests fledge at least one young. And if predation is a problem for cardinals, why don’t the males try to blend in a little more? Our NestWatch team has some answers, fed by details of cardinal nesting behavior gleaned from the 268 nesting attempts reported to the program so far. Here’s project leader Jason Martin:

Jason MartinThe answer may lie in their long breeding season. Cardinals do not migrate and can begin building nests as early as late February. They can continue nesting into late August or September, giving them plenty of opportunity to raise one or two broods of young per year.

Another factor could be that cardinals are habitat generalists. They can nest in open woodlands, dry shrubby areas, disturbed tangles, suburbs, backyards, and even deserts. And they seem to put their nests pretty much anywhere: a recent study in Texas found that cardinal nest sites weren’t particularly different from sites the researchers chose at random. This suggests that cardinals may not be limited by suitable nesting locations.

Cardinals build their nests in live trees, shrubs, or vine tangles, anywhere up to about 15 feet high. Higher nests, and nests placed in denser tangles, seem to offer some relief from predators. The bright male carries nesting material to the female, who does most of the building. She uses her big beak to crush twigs until they’re pliable, then bends them around her body to make a nest cup that fits her, wedged into a small fork of branches for support. The nest is a sophisticated structure that takes 3–9 days to build. By the end, it’s about four inches across and three tall, lined with a snug layer of grapevine bark and fine grasses and pine needles.

But how does the male get away with being so colorful? The flamboyant males sing from high perches and do not trade their breeding plumes for a drab winter coat—they seem like obvious targets for hawks. It turns out that male cardinals are probably bright and loud for the same reason: to advertise what good mates they’d make.

According to the Birds of North America Online, brighter males have higher reproductive success, hold better territories, and offer more parental care. The intensity of a cardinal’s redness is related to what he’s been eating. So when females see a bright male, it’s a signal that he’s healthy and holds a good territory. (Interestingly, recent research by Amanda Rodewald, the Cornell Lab’s new director of Conservation Science, shows that this relationship may be getting less reliable for cardinals in urban areas, because of the novel food sources available in town.)

By responding to redness as a sign of a promising mate, females have encouraged the evolution of bright coloring in males. This process is called sexual selection, and it’s an everyday example of a process that can lead to extraordinary creatures like the birds-of-paradise. At the same time, the female’s muted colors provide her (and her nest) with a protective camouflage that the male lacks. Furthermore, cardinals tend to have high survival rates, possibly because they don’t endure the stress of migration. The oldest recorded cardinals lived to be at least 15 and a half years old (one recorded in Pennsylvania and another in Virginia).

If you are lucky enough to find a cardinal nest this year, won’t you help us learn more about this fascinating species? Last year, NestWatch participants monitored a record 81 Northern Cardinal nests. Can we get more in 2013? Head over to NestWatch for tips, stats, and focal species information, plus details about how to monitor nests safely as part of this great, free project.

(Image by Daniel Behm via Birdshare. This post was written by NestWatch project leader Jason Martin and program assistant Robyn Bailey.)

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65 Comments

  1. Stafford-Ames Morse says:

    Love the info on Mr Cardinal. Can you set it up so one only needs to click “Print”. Our Bird Club is in a retirement village and we take the article(s) and post them on our board in the main loby for all to read and enjoy. For now, we need to cut and paste to do so. Many folks do not have a computer or know how to use such.
    Thanks.

  2. robert huesman says:

    For what its worth, and I have only seen this once, I had 26 pair of northern red Cardinals visiting everyday for over a week during a very cold winter. Each pair developed a small depression in a winter snow cover. The female maintained the depression in the center the male standing guard at the top edge of the depression these depressions were no more than 2 feet apart scattered is all over my small backyard this happened over 15 years ago and I have never seen it since. Perhaps being a bit social also helps Cardinals survive winter, and predation.

  3. judy Burd says:

    Interesting. The cardinals in my yard have chosen a holly bush for their nest site. However I wonder about the birds smarts since it attacks my side mirror on my car and my back window several times a day. I finally painted the window with white wash to keep him away. Sadly couldn’t do that same for my car and the bird broke the mirror.

  4. KT says:

    I have had a pair of cardinals nesting and living in my yard for at least 35 years. Chances are it’s not the same pair, but it may be possible it is the same family line.

    Every summer, I have the joy of watching their fledglings learn from the dedicated teachings of both Mom and Dad, who are “hands-on” parents.

    I do my part by furnishing squash seeds and hard-boiled egg yolks during the nesting season. The nutrients in both of these foods seem to be what is needed for both Mom and her young. She lets me know if I miss her feeding time!

  5. Randy Baker says:

    In 2011 cardinals built a nest approximately 4 feet off the ground in a maple leaf viburnam bush 12 inches from the north wall of the house. 3 eggs were laid and all were destroyed. An attempt to renest was made with no success. In 2012 a nest was built 5 ft off the ground in a different maple leaf viburnam 3 ft from the north wall of the house. 3 eggs were laid with all three being destroyed. Location Oregon Twp., Lapeer County, Michigan

  6. Tatum Young says:

    Our male is name Pretty and I call him every morning to come and eat. Sometimes he brings Mrs. Pretty with him and all summer we see new babies. He is a wonderful bird and as long as he comes we will continue to feed him and his family.

  7. Debbie says:

    I am wondering if you could give me some advice. I live in the Adirondack mountains of upstate NY. Can you tell me how to attract Cardinals to my home? What is the best type of feeder for them and the best food?

  8. tracy says:

    Hello,
    I am interested but surprised with this article. I have read in several sources that Cardinals only live for about one year! Your article says up to 15 years. How can literature vary so much?

  9. Cathy Sears says:

    I was fascinated to find out how the female Cardinal builds her form-fitting nest: Ms. C. just winds beak-bent twigs and other nesting materials around and around her body!

  10. Julie McClure says:

    My neighbor reports seeing as many as 7 pairs of cardinals at his feeder. Currently there are 4 males and a couple of females that use the feeder. Don’t know if they are members of the same family or not. There is one large male and female (couple). Will encourage neighbor to go to this website and enter info. I reported on one nest site next to our home last year. Great website. Thanks! Julie

  11. Linda McDermott says:

    Your article should have mentioned the cardinal’s “mating dance”. He was shows off his bright colors in a very interesting display. I was lucky enough to see it at my feeding station. I know what it was because of the stylized behaviour which led to an obvious result.

  12. last year at my feeder there were three broods of baby cardinals learning how to feed from may through august. there were as many as nine cardinals on the feeders this october. i dont know if the babies were from the same prents or diferent ones, but what a cute sight. i called them my little terradactles!

  13. Gwin Hanahan says:

    Red seems to be an interesting color among animals. Thank you for the explanation about the red of male cardinals who brighten my day at the feeders.
    I have heard that among night-active tropical fish, red is a popular color.
    I wonder…how does the eye of a fish or a bird perceive the color spectrum? Is it in an some way similar to humans’?

  14. Cindy Victor says:

    Thank you for this information. Just this morning I watched a male cardinal feed a female as they perched on a willow tree. He would go to the feeder, then back to the tree where she awaited him.

  15. Mila Paul says:

    I learned at a seminar given by Prof. Matt Tarr at NH Audubon that cardinals are red because of the red berries they eat. When honeysuckles started invading the Northeast, people started noticing the cardinals were even redder than they used to be. The cardinals were getting more color than they had before because of an invasion of lonicera species in their food supply.

    That color is just one example, another is caterpillar-eating birds that eat plenty of bright green caterpillars tend to have the brightest yellow feathers.

  16. Deb says:

    Hi
    I read your article with great interest as Cardinals are a favorite bird to photograph. You state that their diet enhances the hue of the feathers. For the most part, the Cardinals I encounter are seed eaters, especially oily sunflower. Can you share how the seeds metabolically breakdown in their system to produce a “redder” bird? Thank you.

  17. Barbara Ann Krebs says:

    Have a very bright Red male Cardinal, who for the past two years, will land on my clothes line and call to lot me know his seeds are low. he will watch from a nearby oak tree,as I fill the feeder and returns to eat then sings.

  18. Marion Neigh says:

    We have had cardinals sucessfully breed in our garden every year. In fact we have a new young pair. The old pair were with us for years. The male would bring the grey fledgelings to the area below our feeder and feed them the sunflower seeds – a lovely sight! They always nest in our Japaese lilac tree.

  19. John Zang says:

    I’m amazed to learn of the long life span of the Northern Cardinals. We have had many in our suburban backyard for many years. We’ve provided several bird feeders and a bird bath(heated in winter) for over 20 years which has provided us much pleasure in viewing bird activity. The Cardinal is our favorite and soon we will be hearing the male’s (mating?)calls. I’ve actually learned to closely imitate their calls to the point where they respond with additional calls.

  20. Suzanne says:

    I love Cardinals, however, they do not populate this part of the United States. I saw my first Cardinal last spring while visiting St. Louis, MO……beautiful bird!!

  21. Rosemary Thomas says:

    My resident cardinal pair raise large families each year. This winter I have 8-10 cardinals at a time at my feeders daily — morning, noon, and evening. I suspect they are an extended family. Can’t tell what generation. Boomerang kids?

  22. Algird Kapacinskas says:

    We have 4 to 6 males and a dozen female Cardinals in our backyard here in Rock Island, IL. The ravine in back provides cover and feeding for dozens of animals in this habitat.

    We have one we call “Mr Big” an ample malpha male that rules the patio with an iron beak.If it weren’t for squirrels we be living outside being kicked out by him.

    Around dusk he hops up very close to the patio door and we check each other out.He is quite impressive.

  23. Richard Bartels says:

    I’m a birder and I live in San Antonio, Texas.
    I’ve noticed the cardinals around here seem redder than those in the northern states.
    It also seems to me that the cardinals get redder the farther south I get in Texas. Also a hundred miles south of SA the pyrrhuloxia seem to have more red on them than they have around the SA area.
    Anybody else notice this or have an explanation of why this could occur?

  24. Paul says:

    I have been receiving the Cornell Lab reports for several months now, and I have fallen in love with birds and things that affect birds. Thank you so very much for the work you do.

  25. John Ingle says:

    Thanks. I’ve wondered about the bright color, as inconsistent with safety. One little nit: Look up the phrase “begs the question.” It is not the same thing as “raises a question,” which is what you meant here. If something “begs” the question, it assumes a particular answer to that question and builds upon it in making an argument or a point. This is only annoying to one with a lawyer mentality,although in fairness lawyers misuse the phrase as often as non-lawyers.

  26. chris dasilva says:

    So that’s why they’re so pretty!

  27. ginny says:

    Great article! I know of at least 3 pair of cardinals at my feeders this year that I have been watching, I live by the river and have grape vines by my house, but have yet to find a nest. I see a few Jays also.

  28. Sheldon Robinson says:

    nice article on cardinals- am feeding 4 pair at feeder- due photos- have many good pictures of birds-it’s my hobby- feeding 40# of feed a week

  29. carol anderson says:

    Am in NC and have several cardinals that come to feeders at the same time. I always thought (at home in NY) that cardinals were ground feeders and territorial. Here in NC I have seen 4-6 males/females at the same time and they do get on the feeders.
    Very interesting that cardinals can live to be up to 15 yrs old!
    Also note that all the birds seem to really like the bird seed that Cornell lab sponsors (nut and fruit). And I know that the seed is good for the birds. Thanks.

  30. Renee says:

    We’re all taught at an early age that bright coloring can also trick a predator into thinking something may be poisonous. Could that also be the case with cardinals? Also, we’ve got a bright, brave boy that sings to us every morning in our backyard, but I haven’t seen a nest. Should I still report his location, or wait to find a nest?

  31. Vincent J. Messina Jr. says:

    I still think that there is a more subtle and at the same time, a more dramatic reason why male birds like cardinals are brightly colored: Bright color will attract a predator. What? Predatory birds like hawks use sight as a tool for finding food. Is it better for a species to lose an individual male or female? It is obvious that the survival of a species is directly linked to having breeding females. If females are caught by hawks and other predatory species, the population must drop. It is simple math: Less females equals less offspring. This has always been my theory. A brightly colored male is not only a superior catch for the female, but a superior decoy to protect his offspring.

  32. Linda L. Martin says:

    I have a few very close up pix of a robin on her nest, some with the resulting one chick, right outside my window last year. If you think you’d like to see them/use them, let me know where to send them.

    LM

  33. Bonnie Welty says:

    I have six or more Cardinals in my yard year round.I live in old neighborhood with mature trees but have never seen a Cardinal nest here. Across the road from me the Clintonville Woman’s Club’s club house is built along a wooded Ravine. Last summer Cardinals built their nest on top of one of the outside lamps by a doorway facing the ravine. I do not know whether that nest was successful.

  34. I thoroughly enjoyed reading about this beautiful red bird. I knew they nested often during the season, and this article further explains why they survive at high rates. Thank you for sharing this good info.

  35. Chris DeBaun says:

    Do cardinals mate for life? I wonder about this because I have a male/female pair who use my feeder 3 or 4 times a day. I never see the male without the female or vice versa. Their tink-tink calls wake me up, sometimes even before the sun is up, and I see them throughout the day.

  36. Debra says:

    Only one pair of cardinals ever visits my backyard feeders and their behavior is odd to figure out. I understand when the male is feeding seeds to his mate (nesting time), yet other times he’s crabby and chases her away from the food! I put out a variety of foods in more than one spot on the ground where he only takes a tiny bit and then flys off (fear of predators). Better explanations anyone?

  37. Christine W. Kulikowski says:

    It’s 20 years ago when a cardinal couple built a nest in a holly bush literally next to my window. We watched through the window, like one in a habitat to view the birds. But I was not impressed by their nest building prowess. Their nest was sloppy and the parents were constantly shoring it up. Once an egg fell out. I carefully returned it and used a bit of plywood to make a platform for the nest. Another time a cowbird left an egg while the parents were away. I removed it. And then a fledgling fell out. I put it back. All through this time they casually watched us too. The most endearing behavior was at night. They wanted the lights out. They covered their eyes by the wings. And if They caught sight of us they scolded loudly until we put the lights out.

  38. Sarah says:

    I feed the birds on a high brick wall onmy front porch where I can watch out my den window
    In the past the cardinals have always come in male female pairs and the male would feed the female. This year I have 4 males and three females. They come one at a time. They do not associate with each other except that one of the male cardinals is very aggressive. He runs at and attacks any bird on the wall. In the past the only birds that did this were bluejays and doves. Ironical about the doves. This male cardinal is defintely the top king pin, even the cats don’t fool with him.

  39. Diane says:

    I’ve had the same experience with a pair of cardinals where I work. For the past 2 years I have been feeding a male peanuts and sunflower. During breeding season he will literally dive bomb me when I walk out the door for his peanut, often feeding her before he eats, and is a very attentive mate and parent when she’s on the nest constantly flying back and forth to feed her and the babies. However he always chases her away during the winter and will not allow her to eat, often not eating himself to chase her away. He’s extremely territorial and will chase any other male coming into the area. I am not able to get to the nest, somewhere in the middle of very thick underbrush along side a marsh. He’s a very intelligent bird and will come when I whistle to get his peanut. But I find his crabby nature toward the female during the winter very odd too! I have noticed the past couple of weeks he is allowing her to eat again, hasn’t started feeding her yet though. I live in NE Ohio.

  40. Edward McHale says:

    Several winters ago at Ford House in Grosse Pointe Shores, Michigan which is on Lake St.Clair, I saw a bright orange Male Morthern Cardinal. Recently at the same location I spotted a House Finch with a bright orange splotch on its chest in the middle of its typical reddish chest. So local diet variations can be a color factor.

  41. Eric says:

    A week ago I saw my first-ever cardinal in the northern Minnesota town of Bemidji; I have lived here since 1990. They are common in the southern part of the state and now seem to be moving their territory northward.

  42. Sue Austin says:

    We’ve had multiple pairs of Cardinals for years now, this year we’re up to 9 pair plus 6-7 young ones (still pretty gray though they’re beginning to brighten up). The brightest pair has been here over 3 years, male is a brilliant deep red, female is overall much brighter than others, lovely warm colouration heightened by a large deep orange blotch on her chest, really stands out. Their preferred nesting site is a big eglantine rose equipped with horrendous thorns guaranteed to discourage predators, & as a result they always seem to be feeding young, and the resident population increases steadily every year.They dote on Viburnum trilobum & deciduous holly berries, but have been seen to feed cheerfully on poison ivy, wild grape,
    blackberries, etc. And of course tons of black oil sunflower seed which they demand imperiously when their supply runs low!
    We love to see them through the year but we especially appreciate their bright and cheerful presence during our long gray winters when they bring warmth not just to the landscape but to our spirits as well.

  43. Harry DeVries says:

    I live near Niagara Falls Ontario Canada. We have cardinals throughout the year. I constantly feed them in winter to keep them in the area. We also have a returning pair that tend to return to the same nest each time. They are early risers, often the male calls can be heard an hour before day break.

  44. Mariko says:

    For the 18 years I have lived in my house, I have had many cardinals feeding at the feeders, and nesting in the honeysuckle. Recently, more houses were built behind me on farmland, and I have gone from having as many as 12 cardinals frequent my back yard to none ! I am completely mystified, because I see them around the neighborhood. Wonder why they have suddenly stopped coming?! I really miss them.

  45. bev rock says:

    I say a bright red male feeding a tiny baby cardinal in my crepe myrtle tree which is outside my bedroom window so I can stand and watch the action. He flew back and forth feeding the baby..I was so thrilled to be able to enjoy this gift from the universe.

  46. taitianna says:

    Why are male cardinals bright red in color?

  47. Marshall Smyth says:

    Tatianna, according to the good info above, the short answer for why male Cardinals are bright red is they evolved that way because over the time of evolution, the girl Cardinals breed with the brightest red boy cardinals. And, the male cardinals get the most red if they eat the best healthiest food. The female cardinals like to breed with the healthiest male cardinals, and the healthiest male cardinals are usually the brightest red.

  48. Deborah Martin Allen says:

    I live in Dallas, Tx. I bought my 1st bird feeder this year. Cardinals are seen often around here. I have put out Cardinal food. The male cardinal is very cautious. Early this Spring a male, female and fledgling would come eat. There may be two families now. They built a nest in my Indian Hawthorne bush. It is abandoned now. I do not know why! Why? All the birds and animals get along. I have house finches, a bluejay, a bunch of doves and 2 squirrels come. As long as they feed on the ground, I let them eat along with a rabbit. But when they get on the small bird feeder, I run out of the house fussing at them like a maniac. One day I woke up to 2 squirrels on the feeder with their bottoms in the air eating all the food. At the end of the day the full feeder was empty. I’m going to get striped sunflower seeds next, because they don’t like them. P.S. All the birds ignore my 14 year old dog.

  49. Joe Beleski says:

    We live in Vermilion, Ohio and every year the cardinals build a nest 2 feet from our sunroom window in a viburnum shrub…..5 feet off the ground. The female began building her nest 2 days ago and it looks like it’s almost complete. The male is often seen but does not “help” in the building, at all from what I can see. One interesting sidenote: Before the nest began….the female would fly into the bush, hop around looking for a suitable spot, then begin chirping loudly until the male would arrive, at which time she would remain motionless and silent…almost like she was hiding from the male. After about 30 seconds, she would fly off with the male following. I took this to mean she was indicating to the male “where” she wanted to build the nest. I expected the male to help…but no such luck for Mrs. Cardinal.

  50. Pam says:

    I have a pair of cardinals in my southern WI yard who have nested about 4 feet off the ground in my hardy climbing rose bush. Just peaked tonight after I saw the male go to the nest. There are 2 babies and 1 unhatched egg. The chicks are obviously very newly hatched; so tiny. The mother looks like a fairly young female. I scared her off when i watered some flowers but the brave father flew in, probably to feed them.

  51. Joe Beleski says:

    Mrs. Cardinal is proudly sitting on eggs (3 of them) outside our window, and doesn’t see to mind up living just a few feet away, and with the window open. Mr. C didn’t help with the nest building, and has only been spotted ONCE in the past 4 days. You would think this Romeo would help out with the housework and food…but no…..he’s NOT a stay-at-home dad. Oh well!

  52. Joe Beleski says:

    Mrs. C still tending to her eggs, but Mr. Cardinal is putting on a show for us here in our sunroom. This morning, we discovered another bird nest in the adjacent and identical bush, but this nest has hatched baby birds and the parents seem to be similar to sparrows but I’m not sure what they are.
    Just minutes ago, Mr. Cardinal ATTACKED this nest, chased the mother off, and stole what looked to be some food. He then checked out Mrs. C, but she was gone (been coming and going all day). Well, after a minute or so, Mr. C again climbed into the sparrow? nest and took another morsel of food and flew off. The mother of the babies then arrived and is noew tending to the nest. I don’t know what to expect next…but I’m worried Mr. C is going to kill the baby birds.

  53. Joe Beleski says:

    About an hour has passed, Mrs. C is sitting on her eggs, and Mr. C again attacked the chicadee or whatever’s nest. This time, I watched him stick his beak down the baby bird’s throat, I suppose to remove food, and then flew off. I can’t explain this behavior since I know next to nothing about birds……but this seems crazy!!!

  54. John Stewart-Smith says:

    If male Cardinals are red because they eat red berries what do female Cardinals eat? Do Blackbirds eat blackberries?

  55. Jack Ahearn says:

    I notice a male cardinal come to my platform feeder yesterday morning with a short twig in his beak. He returned frequently until early evening every time with the twig. It’s a strange sight. I assume the twig is stuck. He eats safflower seeds out of the side of his beak where the twig isn’t. I am trying to figure out how he will extract that foreign object, and how he can crack seeds open. Tallahassee, Florida

  56. Nancy Todd says:

    I have a bright male cardinal that sits in my oak tree every night. He just sits there and when I take my dog out at night, it does not disturb him. He stays in the tree just above my deck.
    Why is he there every night, alone. And the branches he sits on are only about 10 feet high. The area is also close to the edge of the tree, not close to the tree.

    • John Stewart-Smith says:

      Because he is fascinated by you and your dog, and cannot miss an opportunity to see what you two get up to next.

  57. John Stewart-Smith says:

    Or, maybe, because he has found a safe night-time roost?

    • Nancy Todd says:

      John, I was thinking a safe roosting spot for night. Does this mean he has not mate. Anyway, I look for him every night, it’s interesting. Thank you.

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  59. Alecia says:

    I am not usually much of a bird watcher, however, I discovered a nesting pair of cardinals in a waxleaf ligustrum right outside my office window (I work from home). No eggs, so far, but I sure hope they stick around! They are a lovely change from grackles, doves and mockingbirds!

  60. Steve kern says:

    Sure do wish we had cardinals in Las Vegas. Absolutely my favorite bird! So strikingly beautiful, and handsome!

  61. Steve kern says:

    While visiting my parents home state of tennessee one year In May, I was fortunate enough to follow a bright red male back to his nest in a big holly bush, to find five babies rearing their heads when I would imitate his call!

  62. Lori Wyde says:

    I have a cardinal nest in a butterfly bush off my back deck and this morning I saw the mom and dad cardinal (what appeared to be)attacking another bird. Do other birds try to kill the babies? Or did it just accidently fly into the area and the cardinals were being protective?

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