Shake It Out!
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A couple of weeks ago I caught this image of a Pied-billed Grebe shaking out its feathers after a bout of self-grooming. The little bird really seemed to be enjoying itself. It doused itself with water, then, methodically cleaned itself from one end to the other by rubbing itself with its beak. When it was all finished, it fluffed out its feathers and shook vigorously, scattering water droplets as it did. The grebe looked very contented when it finished. It plainly was enjoying itself.
I see waterfowl of every species engaging in this behavior often. It’s not just a question of neatness and personal hygiene for these birds, it’s also a matter of necessity. Feathers aren’t naturally waterproof. They can become waterlogged and, if they do, the bird loses its ability to float on the water’s surface. It’s particularly a potential problem for one of these little grebes because they dive for their food.
Getting the dirt and dust off is important, because dirt can absorb water and make it much harder to stay dry. But, beyond that, the birds must find a way to waterproof their feathers. A grebe like this one will dive once or twice a minute when it is feeding and stay submerged for 15 or 20 seconds at a time. That’s a lot of exposure to water and potentially a huge problem for the grebe.
Grebes and other waterfowl have evolved a solution. They have glands on their backs that secrete oil which, when rubbed on the birds’ feathers, renders them waterproof. The grebe rubs its oil glands with its beak, then wipes off the residue on its feathers. So, this cleaning ritual, beyond being pleasurable, is also a vitally important waterproofing activity for these birds.
Image made with a Canon 5Diii, 400 DO, aperture preferred setting, ISO 1600, f5 @ 1/500.