Anatomy: Culmen

Culmen shown on European starling (photo by Chuck Tague)Winter is lousy for field work but it’s a good time to curl up with a book and learn something, so in that spirit I’ve decided to (finally!) learn more about bird anatomy. 

Yes, I’ve watched birds for decades but that doesn’t mean I know the scientific names for the parts of a bird.  During research on various blogs I’ve encountered many technical names, but what do they mean? 

Maybe the names stump you, too.  Why not make this a group project?  So here’s the first in a weekly series on bird anatomy. 

What is a culmen?  It sounds vaguely like… ummmm…. “culminate,” a related word. 

Answer:  It’s “the dorsal ridge of the bird’s bill.”  For us laypeople, it’s the top of the beak from the head to the tip, as shown by the green line. 

I encountered “culmen” when I looked for the length of the pileated woodpecker’s beak.  The answer was “the male’s culmen is 43-56 mm” so I had to look up two things:  the meaning of culmen and the conversion from millimeters to inches.

The shape of the culmen is a useful field mark for identifying birds.  Some bills (culmen) curve up as on American avocets, some are straight, and some curve down as on the long-billed curlew.

So now you know.

(photo by Chuck Tague with graphics added by Kate St. John)

5 thoughts on “Anatomy: Culmen

  1. I have found a flock of black white red birds living off the catfood in a couple empty lots where feral cats reside with the birds cannot identify them. They are too big to be woodpeckers. I am in CT. Help

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