Possum bite marks on chewcard.
The extensive crushing along the margins is characteristic. Isolated bite marks may or may not also be evident. The crushing and biting can extend beyond the baited parts of the chewcard.
Crushing alone is not necessarily enough to identify possum because other species can also crush chewcards. So, try to dentify individual tooth marks as well.
Photograph: courtesy and © Manaaki Whenua – Landcare Research