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First published September 1, 2017

Sometimes scratching is not for an itch, but to get rid of pests and preen feathers. Male Snail Kite above.

GOT AN ITCH?

Sometimes when it itches, we just have to scratch it. Birds seem to have the same problem. But think about it, whereas we humans have pretty good flexibility and good hands and fingernails to scratch with, birds are really limited in their scratching tools. They have claws and beaks, and they have places that are almost impossible to reach. Just as we humans have to really stretch and reach to get that itch in the middle of the back, birds have to stretch and reach to get the same spots on the back, but also their legs and claws just don’t seem to get to all the spots that itch. Consequently, we can observe some pretty fancy contortions as the birds “Scratch that Itch.”

Except that birds are not necessarily scratching an itch. Their scratching activity is actually a critical part of their feather care, essential to their very survival. Birds must smooth out their feathers to keep them in good condition and prevent them from wearing prematurely. Birds have a preen gland at the base of the tail, which excretes a waxy oil film that is necessary for the maintenance of their feathers. They access this gland with their bills and spread the oil throughout their bodies by running their bills the length of the feathers. This Brown Pelican is in the process of obtaining the oil from its obvious preening gland prior to spreading it throughout its feathers. (above) Of course, this process is limited to whatever parts of their bodies the birds can reach with their bills. This can lead to interesting bird contortions. Roseate Spoonbills (right) have more difficulty than birds with smaller bills; such as Yellow-rumped Warblers, Hairy Woodpeckers, Dunlin, Merlins or even Bald Eagles.

But birds that scratch with their claws are engaging in a different kind of feather care. Many critters, such as lice, flies and mites, have evolved with, and live their entire lives on, birds. Some of these critters actually eat the feathers themselves. The oil from a bird’s preening gland helps keep these pests under control, but where the birds can’t reach with their beaks, they scratch vigorously to rid themselves of these unwanted varmints, giving us the appearance of scratching an itch. Here are a few examples: Ruby-throated Hummingbird, Tropical Kingbird, Scissor-tailed Flycatcher; American Avocet; Long-billed Dowitcher, also displaying its flexible beak tip; Black-bellied Whistling Duck; White-tailed Kite; and Snail Kite.

Sometimes a baby bird, like this Sandhill Crane, needs help scratching from Dad (Photo 16). Then too, scratching on the edge of a post can be almost as good as a claw. Crested Caracara (Photo 17). And sometimes, it’s just necessary to scratch, and ignore any busy-bodies that might be amused by your itch. Limpkin (below).

So the next time you need to scratch that mosquito bite just think how lucky you are that when the bite is gone you won’t have to scratch again until something else comes along that causes an itch. Unlike birds, our scratching is only occasional, and not a survival technique that we need to learn. Of course, in our human parlance “scratching an itch” has come to mean giving in to some activity that certainly can become dangerous: “I’ve got an itch to go sky-diving;” or “… drive 110 miles an hour” on a back country road; or “… ask that good looking girl for a date.” You get the idea, but maybe you can tell us about your itch that you either did or did not scratch, and whether you wish you had, or not. Your tale of woe or success could be very interesting.

For a more detailed explanation of bird feather care, see Frank Gill’s explanation in his excellent book, Ornithology, the source of much of my information contained in this column. For a video of bears scratching an itch, see: nerdist.com/planet-earth-ii-gives-us-these-wonderful-dancing-bears/.

Click thumbnails to see larger versions

Yellow-rumped Warbler

Hairy Woodpecker

Dunlin

Merlin

Ruby-throated Hummingbird

American Avocet

Bald Eagle

Tropical Kingbird

Scissor-tailed Flycatcher

Long-billed Dowitchers

Crested Caracara

Sandhill Cranes (Male & chick)

Black-bellied Whistling Duck

White-tailed Kite

Island Scrub Jay (Channel Islands)