Jump start vs. rolling take-off

Posted January 24th, 2011 by kcorliss. Comment (0).

Feather wear is a problem. Over time a bird’s feathers become ragged, worn, faded and less effective. Quite beautifully, nature has provided a temporary fix for this ongoing shortfall. It’s called molt.

I won’t get into the various molt strategies used by every bird species as it is quite complex and extremely varied. Suffice it to say, however, without a molt–be it once or twice per year–birds would die rather quickly without the ability to fly.

Speaking of flying, I captured an interesting image this morning in my own back yard. It’s a white-breasted nuthatch at my mealworm feeder. The interesting part is this constitutes the first time I’ve seen one feeding here. That makes four confirmed species having used this feeder. They are black-capped chickadee (by far the most common), house sparrow (can’t pick your guests), dark-eyed junco, and now the nuthatch.

More importantly, the photograph illustrates the bird just taking flight. Notice anything? That’s right, no use of the wings at all. The thing looks like a harrier jet using vertical takeoff technology. It happened so fast the human eye can’t pick this up, but the bird simply jumped into the air before employing its wings. I contend this is a strategy to protect its most important asset–it’s feathers.

Consider, if it were to begin flying from a perch, its wings would necessarily encounter obstacles–in this case the feeder–and incur “battle damage” to a certain extent. Instead, it clears the obstruction by jumping, then begins flapping. Ingenious.

Contrast this technique with that of wild turkeys. I took this shot last weekend while snowshoeing. It seems quite obvious the birds must pump its wings a number of times (10 ground strikes in this case) before achieving the necessary speed which it needs to sustain flight. By doing so, this species must sustain more feather wear as its wings hit the ground. But, as opposed to nuthatches, turkeys seem to place more importance on its feet. That is, most often the birds will run instead of fly when avoiding potential predators, and even while feeding or looking for food. A strategy which has served this wily bird quite well.

Correction 1/26/2011: After looking more closely at the photo, I was wrong. The trail of snow impressions left by the turkey actually shows a landing versus a takeoff. But the point remains–these are heavy, lumbering, mostly ground-dwelling birds which sustain a much higher degree of feather wear due to their size and proximity to the ground when engaged in flight activities.

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