WATERTHRUSHES AND DIPPERS

     Louisiana waterthrushes and American dippers are unrelated birds that have characteristics in common because they adapted to similar habitats.  Each species of life is molded by its habitat so that that life can use its habitat efficiently for survival and reproduction.  

     Waterthrushes and dippers nest along running streams and search for invertebrates in those currents, the waterthrushes in eastern North American woods and the dippers along swift mountain streams from Alaska to Panama.  The habitats of these birds obviously don't overlap, but the birds occupy the same niche in those habitats.  And both species bob up and down while walking along streams, probably to mimic small debris bouncing in the current, which is a form of camouflage, or blending in, to be invisible.  

     Louisiana waterthrushes are a kind of North American warbler that patrols the stony edges of woodland streams for aquatic invertebrates to eat.  They pump their tails up and down as they walk along streamside shores, which, I think, camouflages them along the shores of streams.

     Waterthrushes are six inches long, brown on top and streaked below, again to blend into their environment.  And they are tough to see until they fly, or otherwise move.  

     This species of warbler is in North America only to raise young in leafy nurseries in streambank notches, or behind exposed tree roots in streambanks.  They winter in Central America to avoid northern winters.

     Males sing loud songs to establish nesting territories and attract mates for nesting.  Those songs have to be loud so the birds can hear them above the musical babble of the waterways they nest along.  Each female lays four eggs in her nursery.   

     American dippers are six and a half inches long, stout and sooty, with short, upright tails.  Their gray feathering camouflages them among the mid-stream rocks they perch on between feeding forays in the water.  They bob their entire body up and down, as if doing push-ups.  This, too, is a type of camouflage to avoid hawks and other kinds of predators.

     Dippers swim and walk underwater in search of invertebrates to ingest.  They swim with their wings, as if flying.  These birds produce lots of body oil to keep their feathers waterproof, and to stay warm while searching for aquatic invertebrates, crayfish and small fish.  They take their prey onto a rock where they kill and swallow it whole and head-first.

     American dippers are permanent residents wherever they live along swift streams.  Males and females trill loudly to each other the year around, to be in contact with each other above the roar of the tumbling water.  

     Dippers build globe cradles of grass and moss, with an entrance on the side of each one, in a streambank, rock ledge or behind a waterfall.  Each female lays two to four white eggs in her nursery.  

     Louisiana waterthrushes and American dippers have traits in common because they live in similar habitats.  Both species are quite interesting to experience, or at least know about.

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