This American dipper is equipped with an extra oxygen capacity at a lower metabolic rate in the blood and has a thick coat of wings; it is able to manage cold water during the cold months, as Cornell suggests that they swim and under the stream By walking, catching all the food under water in fast-moving currents. There is only really aquatic song in the continent; this cinclus Mexicans is a small bird in favor of western currents.
source - https://www.treehugger.com/slideshows/readers-photos/photo-ring-new-year-serene-american-dipper/