[obol] creeper behavior

[Darrel Faxon]

OBOLites,
      As I almost never see Brown Creepers at Thornton Creek, Lincoln County during the summer months, the one today was remarkable in any respect, but  its behavior was exceptionally noteworthy.  When I first noticed the bird, it was at the base of a large alder about forty feet from me, and well below eye level.  The morning sun was shining directly on the trunk of the tree.  The tree leaned a bit towards horizontal, rather than being completely straight up and down, and about eight feet off the ground where the first limb branched off, there was a little pocket whch was a bit more horizontal.  As the creeper hitched itself up the tree, when it came to this spot, it suddenly spread its wings and flattened out against the trunk of the tree.  It remained motionless in that position for close to a minute.  In doing so, the bird itself seemed to disappear against the trunk, and all that showed were the two crescent wing bars, which took on the appearance of a marking or growth of lichen on the tree.
      I would have thought that such an action was taken in response to the presence of a predator, except for two things.  One, there were a number of other creatures nearby that would have assumed defensive measures had a predator been nearby, but they went right on with their activities in a normal manner.  A Willow Flycatcher, Song Sparrow, and Townsend's Chipmunk all were within twenty feet of the creeper and showed no signs of alarm.  Two, after the creeper resumed movement, it worked its way around the back of the alder, came out again near the base of the trunk, hitched its way up to the same spot, and repeated the performance: wings spread out, body pressed closely to the trunk, and motionless.  This time it moved its head a bit more, as if preening.  Then after about 30 seconds, it flew to another tree and went on about its normal feeding pattern.
      Has anyone else seen creepers act like this?  Any suggestions as to what the bird might have been doing?  I have two postulations:  One is that the bird considered me a predator, especially since I was above it on the bank, looking down.  I rather doubt this idea.  The other is that the bird was exposing itself to the bright sunlight in response to parasites.  This idea seems plausible, especially since on both occasions, the activity included what appeared to be some brief preening following the spread wing act.  In any case, it was very interesting, and something I never expected to see.
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