Imagine a heat wave, and your body covered in down and feathers. How do birds cope? Well, Saltmarsh Sparrows use their bills to shed excess heat. The late Russ Greenberg, once head of the Migratory Bird Center of the Conservation Biology Institute at the Smithsonian, discovered that these birds' bills convect heat without losing water. The bird actually engorges its bill with blood when temperatures get high, and this radiates high temperatures into the environment. So the larger the bill and the more surface area, the more heat they can lose.
Sadly, Russ Greenberg passed away in October, 2013. We're grateful for all of his work on behalf of birds.
Bills Help Saltmarsh Sparrows Shed Heat
An Interview with Russ Greenberg, Ph.D.
By Chris Peterson
This is BirdNote!
[Newscaster reporting extreme hot summer temperatures]
Imagine during a heat wave your body covered in down and feathers. How do birds cope? Well, some, such as sparrows that live in salt marshes, use their bills to shed excess heat.
To find out more, we spoke to Russ Greenberg, head of the Migratory Bird Center of the Conservation Biology Institute at the Smithsonian:
RG Track 145 21:32 Well we’ve been studying sparrows that… live on the east, west and Gulf coasts all along North America. Well, these marshes are in a lot of ways similar, but one of the big differences among them is how hot they are during the summer. …So we were surprised that we found a lot of variation in the sparrow bills. It was strongly related to the variation in the high temperatures found like in the middle of the summer when these birds were breeding, so that the higher the temperature, the larger the bill.
[Song of the Saltmarsh Sparrow – formerly Saltmarsh Sharp-tailed Sparrow]
RG Track 145 22:33 However, it didn’t surprise us completely because we now know that bills are used by birds as an adaptation to convect heat without losing water. They actually engorge their bill with blood when temperatures get high and this radiates high temperatures into the environment, so the larger the bill and the more surface area, the more they can lose.
The day we spoke to Russ, it had “cooled down” to 90 degrees in Washington, D.C.
“Yah, the heat index was like 122…Made me want to get a bigger bill, I’ll tell you that!”
You’ll find a link to their research on our website, birdnote.org.
Song of the Saltmarsh Sparrow 163475 provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Recorded by G.F.Budney. For salt marsh ambient we used ambient from Cove Island story since Saltmarsh Sparrow recording had significant traffic drone.
Producer: John Kessler
Executive Producer: Chris Peterson
© 2011 Tune In to Nature.org September 2011 Narrator: Michael Stein
ID# SotB-SALS-01-2011-09-20 SotB-SALS-01
More about Russ Greenberg: