Editing Dipper (section)

===Communication===
Dippers' calls are loud and high-pitched, being similar to calls made by other birds on fast rivers; the [[sound frequency|call frequencies]] lying within a narrow range of 4.0–6.5&nbsp;[[kHz]], well above the torrent noise frequency of maximum 2&nbsp;kHz.<ref name=Martens1990>{{cite conference | first = Martens | last = J. |author2=Geduldig, G. | title = Acoustic adaptations of birds living close to Himalayan torrents | book-title = Proc. Int. 100 DO-G Meeting | pages = 123–131 | publisher = Current Topics Avian Biol. | year = 1990 | location = Bonn }}</ref>  Dippers also communicate visually by their characteristic dipping or bobbing movements, as well as by blinking rapidly to expose the white feathers on their upper eyelids as a series of white flashes in courtship and threat displays.<ref name=Goodge1960/>