1918  (1919)  There were many . . . pond beavers and bank beavers, along the stream.
1953  And all along the river we came upon bank beaver.
1964  There may be no attempt to either erect a dam or build a lodge. A tunnel or two into some convenient bank with its entrance below low water mark is all they require. Some folks refer to these beaver as "Bank Beavers" as though they were a distinct species. They are not.