Compare the droppings of the rodent species found in New Zealand.
Norway rat droppings are larger than ship rat droppings and have blunt ends rather than pointed ends. Norway rat droppings are 13.4 mm to 19.1 mm long, ship rat droppings are 6.8 mm to 13. 8mm long, kiore droppings 6.4 mm to 9.0 mm and house mouse droppings are 3.9 mm to 7.6 mm long. Kiore are not often found on the mainland.
Drawings: by Sonia Frimmel