Umbrella pine seeds selection by Hooded Crow, Corvus corone cornix
GUSTIN M. and SORACE A.Abstract:
Probably the Hooded Crow selects longer and heavier pine-seeds to obtain bigger endosperms or to select the full pine-seeds. The old valve absence among the pine-seeds opened by the Hooded Crow also confirms the latter hypothesis.Smaller pine-seeds having a more elongated shape are opened on anvils, maybe because they are more difficult to break open, but the different techniques used to open pine-seeds on the ground and anvils stili need further study.