Chew cards are 2-3mm thick plastic panels with a tasty - to predators - 'lure' pushed into channels inside them. Predators chew the card to get to the lure, and by looking at the teeth marks it's surprisingly easy to determine what animal has done the chewing. The images below will help you identify your pest.
Here's the summary
- Nibbles on one side only = mice
- Bites through both sides = rats
- Punctures = cats, stoats, ferrets or weasels
- Crushed / seagull-shaped dents = possums
Read on for photos and notes.
Identification
Here's how you can tell what animal made different chew marks. Click on the photos for a closer look.

Nibbles
If only one side is chewed away, you've got a mouse, or probably a whole family of them.
Mouse

Bites
Rats will chew right through a card and don't leave dents or punctures like possums or cats.
Rat
Do the quiz
Do you reckon you've got it now? Test your skills on our chew card identification quiz. See if you can do better than your friends!
Acknowledgements
Thank you to Whakaupoko Landcare for the images and guide notes which helped us put together this page.