motacilla tschutschensis disguised as stone on stream bank

abundant adaptation adult alpine altricial beak behavior biodiversity brooding calling camouflage carnivore chick claws common conservation diet display diurnal diving ecosystem endemic feathers fledgling flightless foraging forest freshwater gliding grassland grooming habitat hatching herbivore hovering incubation invasive juvenile loss marine mating migration migratory molt monogamous nesting nestling nocturnal omnivore parasites parental perching plumage polygamous population precocial predation predators preening protection rare resident riparian roosting rural seasonal shrubland singing soaring social solitary species swimming tail terrestrial urban vocalization wading wildlife wings