TORRENT DUCKS AND WHITE-CAPPED DIPPERS

      Torrent ducks and white-capped dippers are unrelated birds that live along swiftly-flowing rivers and smaller waterways in the Andes Mountains of western South America.  And because of their shared habitat, they have characteristics in common.  

     Both species eat aquatic invertebrates from those cascading waterways, but from different parts of them, thus reducing competition for that food between these birds of rushing waters.  The ducks dive to the bottoms of those swift waters and use their beaks to poke among stones and rocks to find aquatic invertebrates, including worms and insect larvae.  With strong legs, and large, webbed feet, as well as slender bodies, these ducks are strong divers and swimmers to maneuver in fast-flowing currents.  

     These dippers don't dive for their aquatic food, but get it in rushing shallows on tops of rocks and along shorelines.  They use their beaks to turn over pebbles on the shores to find water-living invertebrates.  These dippers only submerge their heads or beaks to get food in the shallows.  And they have strong legs and sharp nails to cling to slippery rocks and fast-moving, shallow water.

     Torrent ducks are small, being only 18 inches long and weighing one pound, which allows them to cope well with fast waters.  These ducks live in family groups only.  Both genders have red beaks, but differently-colored feathering.  Males are mostly brown on top and white below, with brown streaks all over.  Their mates are also brown on top,  which offers camouflage, and rusty-orange underneath.  Their ducklings are dark and white-striped, which blends them into their surroundings.  The adults' calls are shrill whistles to be heard above the roar of rushing waters. 

     White-capped dippers are mostly dark on top, with white below and on their crowns.  They are chunky, and also have piercing calls and songs to be able to hear each other beside tumbling water.  Their songs are musical and bubbling.  Their flights are swift and direct, low over the water as they follow the watercourses.  

     Dippers constantly dip as they walk along, picking up invertebrates.  I think that dipping is a form of communication to other dippers, while being camouflaged along moving water.  Their dancing allows other dippers see where their relatives are along swift waterways.  But it's possible that predators would view the dancing birds as debris bouncing in the rapid currents.  

     Torrent ducks and the dippers nest along fast-moving waterways in South America's Andes Mountains, the ducks in small, waterside caves and other sheltering places and the dippers in smaller cavities and on rock ledges.  Some dipper nurseries are located behind protective water falls, where few critters will venture.  Dipper open-cut cradles are made of rootlets and moss.  Each female duck lays three to five eggs, while the dippers lay two per clutch.

      Torrent ducks and white-capped dippers are intriguing species living in difficult habitats.  Most people will never see them, but it's neat to know how they adapted to their shared environment.        

          

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