Blane Klemek: American Dippers
Scottish poet Kathleen Jamie once wrote of a species of songbird that I've yet to observe. She writes somewhat humorously about the curious little bird, describing the bird and its habitat in a way that makes me smile. She wrote in her descriptive, short poem, "The Dipper" . . .
"It was winter, near freezing,
I'd walk through a forest of firs
when I saw issue out of the waterfall
a solitary bird.
It lit on a damp rock,
and, as water swept stupidly on,
wrung from its own throat
supple, undammable song.
It isn't mine to give.
I can't coax this bird to my hand
that knows the depth of the river
yet sings of it on land."
While Ms. Jamie probably wrote about a species of dipper that does not inhabit North America (likely the white-throated dipper), according to the National Audubon Society's The Sibley Guide to Birds, the American dipper, which occurs very rarely in Minnesota, has made a few appearances in the Land Of 10,000 Lakes. But just how many records of confirmed occurrences are unknown.
Of the Minnesota records that I've been able to uncover, authenticated observations have occurred near the North Shore along the fast-flowing, coldwater streams and rivers flowing into Lake Superior. Of all the places in Minnesota replete with a mountainous landscape and clear running rocky streams, the American dipper would find itself much at home here, albeit hundreds of miles east of its normal and preferred range and associated breeding and nesting habitats.
The American dipper is classified as a songbird, or passerine. A stocky little fellow about 7.5 inches long, the short-tailed bird is rather ordinary looking in many respects, save for the bird's very unordinary, un-passerine-like behavior. After all, its common name, "dipper", is for a very good reason.
Of all songbirds, there's no other quite like the extraordinary American dipper. In fact, this species of dipper is the only dipper in all of North America. Other species, which include four other dippers, inhabit South America, Europe, and Asia. The range of the American dipper includes Alaska and southward through the western continental United States, and south to the mountains of Panama.
American dippers are squat birds with rather long legs for their size. To compare with other common birds, the dipper looks like a gray catbird without much of a tail. Likewise, and because of its short tail, American dippers also resemble wrens.
Not very colorful and overall dark gray with slightly brownish heads, both sexes' are identical in appearance. They also have white eyelids that can be observed when the birds blink, appearing almost "flashy" when they do so. But what they perhaps lack in visual beauty is more than made up for by the birds' charm. No other songbird behaves quite like the American dipper does.
As its delightful namesake suggests, American dippers not only submerge themselves underwater when hunting for food, they also constantly "dip", or bob, their bodies up and down as they perch on rocks along their riverine habitats. American dippers are also the only songbird that regularly swims on the surface of the water—their unusually oily feathers are no doubt some of the reason for this amazing ability.
The diving dipper is so suited to its environment, so specialized, that the bird finds itself residing virtually competition-free. Few other birds exploit underwater resources like the American dipper. The astonishing bird is visible one moment bobbing up and down atop river rocks, while it disappearing into the water only to resurface on or nearby the same rock a moment later.
Searching for aquatic invertebrates like various species of insect larvae that hide and crawl on stream bottoms as well as other aquatic organisms such as tadpoles and small fish, including fish eggs, American dippers are experts at finding and capturing these prey items in the swift moving water of mountain streams. They even have the ability to "fly" underwater, using their wings to aid in propulsion, maneuvering, and stabilization in speedy flowages.
One of the interesting aspects of dipper behavior has to do with the belief that the bird communicates with one another, in part, through their bobbing and blinking actions. As anyone can attest, streams and rivers are often noisy environments complete with cascading waterfalls and turbulent water coursing over and around rocks and woody debris.
Though dippers are vocal birds that sing high-pitched whistles and trills, in addition to emitting high and buzzy call-notes, their aural ability in such environments is frequently compromised. Thus, visual displays are important to dippers that are intent on communicating and keeping track of one another.
Regarding physical attributes for their watery world, American dippers also possess two interesting features that better equips them for underwater foraging. In order to see well, dippers have nictitating, transparent membranes that covers their eyes while underwater. Moreover, dippers have movable nasal flaps of skin that close shut so water cannot enter their nasal passages.
One day I hope to observe the amusing American dipper and hear its hearty song emanating from the moist environment of a noisy flowing stream. Indeed, we should all be so lucky as to meet the little dipper of terrestrial environs that "Knows the depth of the river, yet sings of it on land" as we get out and enjoy the great outdoors.
BLANE KLEMEK is a Minnesota DNR wildlife manager. He can be reached at firstname.lastname@example.org