One of my winter walking routes takes me along the banks of
the Kettle River in NE Washington State. During one of these walks I noted a
very distinct bird song coming from somewhere downstream and in front of me.
“Cheep, cheep, cheep” then a “pip, pip, pip”
and that followed by a short, sharp whistle. I surveyed the winter bare
cottonwood branches before me but could not find the bird. Camera in hand I
walked a bit closer to the sound. It paused, I paused, and a moment later the song continued. Still
with no bird in sight I stepped slowly closer. Another pause and then another
repetition of the song. At my closer proximity to the sound source realization dawned I'd been looking to the
wrong elevation. The song source was closer to the ground, to the stream bank. I eyed the bare wild
rose bushes along the riverbank. No bird visible. A few more steps, another bar
of the song, and when I finally observed the bird a question immediately pooped
to mind – “A dipper?”
Later, a bit of research showed me the American Dipper has the spotlight as North America’s only truly aquatic songbird. Birders who have been around the woodlot a time or two may know this chunky, solid gray bird with the slightly brown head as a Water Ouzel. But the uniqueness of the Dipper does not stop there, indeed they are one of the very few birds that can feed by walking along the bottom of a swiftly flowing stream. Whether they are walking or “flying” submerged the American Dipper catches all of its food on or under the water. Another feature sets this otherwise common aquatic bird aside from the rest of the avian flock – not only are American Dippers known to fly directly into the cascade of a waterfall, they sometimes nest behind the falls on rock ledges completely hidden behind the curtain of falling water. While the habitat for Dippers ranges from sea level up into the alpine reaches the prerequisite is clear, cold turbulent streams flowing through forested zones.
Observing the behavioral traits of the Dipper we note it again
sets itself apart from other aquatic birds, which tend to be “tail-bobbers” in
contrast to the characteristic full body “dip” of our subject. Notes Seattle
Audubon Society, “This bobbing, and the flashing of the white upper eyelid, may
be visual communications that are important because of the loud environment that
American Dippers tend to inhabit.”
And yet another trait signifying the unique environmental
adaptation of the Dipper is the creation of a large, mossy dome nest, up to a
foot in diameter, immediately adjacent to turbulent stream waters and utilizing
the spray to keep the moss alive. These living nests are generally covered in a
weave of grass, bark strips and moss with a single opening low and toward the
water. Inside is a soft cup of grass, leaves & moss – a perfect bed for the
eggs.
So on your next walk along the stream side keep an ear open
for the song of the Dipper and an eye peeled for the tell-tale body bobbing of
this unique North American bird.
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