Rock Wrens at Knight's Ferry

The Rock Wren (Salpinctes obsoletus) is a bird of the arid western United States, associated with rocky areas - as the name would suggest.  Light brown in color, this is our palest wren.  It might not look like much at first glance, but closer inspection of this little bird's plumage reveals intricate patterns of delicate spangles and flecks.


Rock Wrens inhabit varied areas of exposed rock, from deserts to alpine regions.  I see them regularly along the rocky bluffs above the Stanislaus River near the town of Knight's Ferry.  Perched on top of rocks, they bob up and down exhibiting their characteristic "deep knee bend" behavior.  In the Knight's Ferry area, Rock Wrens share their habitat with Canyon Wrens, which can be distinguished from Rock Wrens by their rusty red backs and bright white chests.


Like Canyon Wrens, Rock Wrens are not known to drink water, and obtain all the liquid they need from their food: insects and arthropods foraged from the ground.  Rock Wrens nest in the cracks and crevices among rocks, building loose nest cups of plant material.  Curiously, these wrens are known for creating a "paved" pathway of small stones leading to the nest cavity. 

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