Pied-billed Grebes Sink Like Submarines
The widespread divers are masters of their own buoyancy.
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Transcript:
This is Birdnote.
[Pied-billed Grebe song]
Does this song evoke an old jungle movie?
Well, actually we鈥檙e hearing the Pied-billed Grebe, a common resident bird of freshwater lakes and ponds. In addition to its distinctive voice, the small, nondescript Pied-billed Grebe has an even more astonishing talent.
Picture a Pied-billed Grebe, dressed in brown, about a foot long, floating like a cork among lily pads. Suddenly the grebe begins to sink, inch by inch, like a submarine鈥攗ntil it disappears! Thirty seconds later, it reappears, just its head above the water, peering left and right.
When ducks dive under the water, they must leap forward and stroke powerfully with their feet to overcome their inherent buoyancy. The grebe, however, is the master of its own buoyancy. It can squeeze out the air trapped in its feathers and internal air-sacs, and sink effortlessly. As a consequence, grebes swim under water more easily than ducks, which must work hard to keep from popping back up to the surface.
Pied-billed Grebes are found throughout the Lower 48, so if you鈥檙e near fresh water, you could hear the male鈥檚 unusual song . . . before he sinks out of view.
For BirdNote, I鈥檓 Michael Stein.
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Credits:
Call of the Pied-bill Grebe provided by The Macaulay Library of Natural Sounds at the Cornell Lab of Ornithology, Ithaca, New York. Recorded by G.A. Keller. Ambient from G. F. Budney.
Producer: John Kessler
Executive Producer: Chris Peterson
Written by Bob Sundstrom
Narrator: Michael Stein
漏 2015 Tune In to Nature.org March 2018