Experientia. 1976 Nov; 32(11): 1445.

[The waxwing Bombycilla garrulus as a frugivorous feeding specialist (author's transl)]

Berthold P.

Eight waxwings, Bombycilla garrulus, were fed exclusively with vegetable food for periods of 10-18 days. In contrast to other song birds, they maintained or increased body weight during that time, or reduced it only moderately. Thus the waxwing is a feeding specialist which can subsist at least temporarily on a totally vegetable diet.