It is finally spring. Trees are leafing out. The daffodils are at their peak. The lawn has greened, the lawn services are out and the pollen is flying.
And there is birdsong, lots of birdsong. As light comes into the sky the dawn chorus begins - robins, cardinals, titmice, song sparrows.
This is my favorite time of the year. At any moment a migrating bird may stop in my yard to visit the feeders or hunt for insects in the trees and shrubs. The light comes into the sky around the time I wake up and by the time I get outside the birds are singing.
The other morning I was outside with my coffee, listening to the dawn chorus. There was a cardinal singing particularly close by and for once I wanted to watch him sing. I walked along the path to get a better look and stopped when the song seemed to come above me in the apple tree. But where was the distinctive red male cardinal?
Female cardinal (Margo D. Beller) |
There was no male. The singer was the brown female, whose dull coloring allowed her to blend into the bare tree branches near the very top rather well.
I had been fooled, but I'm sure I am not the only one who has made that mistake.
Here is the common thinking about birds: The males, brightly colored to attract a mate, do the singing to either draw a female or defend its chosen territory, its song warning other males of its type to stay away. The duller females mate, choose a nest site, then build the nest for the eggs she will incubate.
But that thinking is wrong, I've learned. Female cardinals sing just as often and as loud as their male counterparts. It turns out female birds of quite a few species do, too.
How have we managed to miss all these female singers? There are a number of reasons, some of them literally man made.
I did some research and it turns out the study of female birdsong has been increasing, and there have been quite a few articles on this very topic.
One problem with knowing if a female is singing: It is hard to tell the male from the female of many types of birds. For instance, I can't tell if the titmouse singing "peter, peter, peter" in my tree is a male or not because the males and females look alike. They are the same size and color. Some singing birds have only the most subtle difference in shading, such as the black head of the male robin and the dark gray head of the female.
Male or female titmouse? (Margo D. Beller) |
According to what I found on the Cornell Ornithology Lab site, a 2016 study pointed out that in a sample of more than 1,000 songbird species from around the world, 64% had females that sing. Many tropical species and some temperate-zone species, such as female cardinals, "sing regularly; while others sing during specific parts of the breeding season," according to Cornell.
Take the song sparrow. A 1943 - yes, that far back - study by Margaret Morse Nice, found female song sparrows sing early in the breeding season, mainly to warn other females away. But she also found female singers among temperate-zone birds including northern mockingbirds, Baltimore and Bullock’s orioles, white-crowned sparrows, European starlings, cedar waxwings and house finches.
To me that is impressive - her study covered nine years of observations - because in many of these birds the males and females look identical.
Both of these birds will sing very sweetly for you, if you have ears to listen. (Margo D. Beller) |
That study is impressive to me for another reason - it's a woman doing the research. Bird research, as in most of the scientific fields, has been a male domain. Most of the researchers have been men and, back in the day, not many of them were interested in traveling outside the United States and were even less interested in dull females, much less whether they could sing. As in so many areas of our western patriarchal society, gender bias determined what we all believed.
That, however, has been changing, slowly.
Here is a sampling:
The Auk, now known as Ornithology, is the peer-reviewed scientific journal of the American Ornithological Society. The society was formed in 1884! This is the place for people who go far beyond Sunday birding, the (mainly) men who make the rules as to taxonomy and other fine details of birds and their lives. Even here you'll find a study on female birdsong, complete with abstract, figures and tables, and references.
Femalebirdsong.org goes further: This site provides actual female birdsong calls and gives you a way to be a Citizen Scientist and gather even more data. There are also links to articles on the topic of female birdsong.
The Female Songbird Project is another a Citizen Science initiative.
Audubon: The granddaddy of bird preservation organizations puts the spotlight on a study "tackling the gender and geographical skew in avian song research."
But wait, there's more: Do a google search of "female birdsong." You'll find all sorts of other articles from mainstream publications including Scientific American and the Washington Post.
If you take away anything from this blog post, it should be to keep your mind open as well as your ears and eyes. Or, to quote Abigail Adams, who in many ways was far ahead of her time, remember the ladies.
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