American Dipper

1/125s at f9.0, ISO:800, Canon Mark IV 1D w/800mm


The American Dipper is also known as a Water Ouzel. This species, like other dippers, is equipped with an extra eyelid called a "nictitating membrane" that allows it to see underwater, and scales that close its nostrils when submerged. Dippers also produce more oil than most birds, which may help keep them warmer when seeking food underwater. It feeds on aquatic insects and their larvae, including dragonfly nymphs, small crayfish, and caddis fly larvae. It may also take tiny fish or tadpoles. It defends a linear territory along streams. Its habit of diving and walking along the bottom of streams in search of food sometimes makes it the occasional prey of large salmon or other anatropous fish. The American Dipper's nest is a globe-shaped structure with a side entrance, close to water, on a rock ledge, riverbank, behind a waterfall or under a bridge. The normal clutch is 2 to 4 white eggs, incubated solely by the female, which hatch after about 15 to 17 days, with another 20 to 25 days to fledging. The male helps to feed the young. The presence of this indicator species shows good water quality; it has vanished from some locations due to pollution or increased silt load in streams.
Grizzly Creek, Colorado
 
03/03/2012