The Collaborative International Dictionary
Rotche
Rotche \Rotche\, n. (Zo["o]l.) A very small arctic sea bird ( Mergulus alle, or Alle alle) common on both coasts of the Atlantic in winter; -- called also little auk, dovekie, rotch, rotchie, and sea dove.
Wiktionary
rotche
alt. A bird, the little auk. n. A bird, the little auk.