Bird of the Week

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Photo courtesy Keith Bruno

This week’s Bird of the Week, compliments of the Weminuche Audubon Society and Audubon Rockies, is the American dipper.

There are very few species of passerine (or perching) birds that have the ability to dive and effectively swim under water. One such rare aquatic songbird is the American dipper, the only North American member of the family cinclidae, a faction of birds known for their charismatic and odd dipping or bobbing behavior exhibited at the river’s edge. Affectionately known in old world terms as a “water ouzel,” this bird is built for the explicit purpose of diving into fast-flowing streams and rivers for food. They are largely thought of as an indicator of healthy riparian zones, as they rely heavily on the larvae of aquatic macroinvertebrates, crustaceans and mollusks found along the clear rock-strewn bottoms of these oxygenated waterways. Threats to their habitat include channelization, pollution and turbidity, often generated from such erosion-producing disturbances as post-fire runoff and adjacent development. 

A bird typically described as stocky or chunky, these slate-gray, round-bodied birds with brown heads have a short tail. Solid bones defy buoyancy and very densely knitted feathers aid in their endeavors in and out of the water. Young birds have yellower bills and can appear slightly speckled similar to their thrush cousins, while adults have blacker bills. They use their disproportionately long legs and short yet strong wings to assist with navigation in the water, propelling them toward food sources. Their eyes are adapted for underwater use and nares have a flap to prevent water intake. 

Last year, the local Weminuche Audubon Society chapter joined in an ongoing dipper NestWatch survey effort initiated in Durango to locate and monitor the presence and reproductive health of this species in the many fingers of the upper San Juan and its tributaries. The Animas has withstood large riverine disruptors over the last 10 years, such as the Gold King mine spill and 416 fire, and concerns over the health of these birds and their local dispersal inspired a group to come together and launch the project. Groups will begin looking for active nest sites this spring, typically located approximately 5 to 15 feet from the water’s edge and often on cliffs or overhung bends in the river, safe from flooding and predator access. 

The next time you’re crossing a footbridge along the downtown San Juan River, linger just a few minutes and listen for the high-pitched bubbling song — it’s the song of the river. Often heard first, it will tip you off to their purposeful flight up or down river. Check out the short film, “A Trout with Feathers” to observe their mastery in action.

For more information on activities and to get involved with local birding events, visit www.weminucheaudubon.org and like us at www.facebook.com/weminucheaudubon/.