The chopper opens its beak wide in attaining some of its clear, free notes. There are no standards for the song of the chopper other than that it be cheerful, lively, and free. Its actions should be lively and alert. The almost closed beak is typical of the roller in full song. This characteristic, plus the much prized low pitched song tours such as the Hollow Roll, Bass, and Koller serve to distinguish the roller canary.
Tone quality is just as important as range.
There is some possiblility that the use of rape seed is at least partly responsible for the lower pitch of their most valued tours. The canary breeder usually specializes in type, color, or song. It is not unusual for a breeder to produce a hundred canaries for every worthwhile bird retained for further breeding. The remaining birds are mostly sold to pet stores. Hence, in the chopper classifiication there appear all colors, shapes, and sizes, and this green bird obviously has inherited much Border Fancy Blood.