This phenomenon is the ability of many long-billed shorebirds to open the tip of a long bill, so as to be able to feed in mud, silt or soil (Erritzoe et al., 2007).
Our call to birdwatchers to document this little known phenomenon as seen HERE attracted the attention of Howard Stockdale from Lancaster, UK.
Howard has been studying the Common Snipe and shares with us his photographic documentation of the rhynchokinesis that first appeared in his Facebook LINK showing the gradual change in the upper mandible shape side on.
Erritzoe, J., K. Kampp, K. Winker & C. B. Frith, 2007. The ornithologist’s dictionary. Lynx Edicions, Barcelona. 290 pp.