The Norway rat (Rattus norvegicus), also known as brown rat or water rat. These are the commensal rats often seen around homes, compost bins, and near streams.

House mice (Mus musculus) are not only found in houses. Accidentally introduced to New Zealand in the 1800s, they are now found from the sea to alpine areas, and they are know to climb high into the canopy of tall forest trees.

Ship rats (Rattus rattus, black rat) were accidentally introduced to New Zealand less than 200 years ago. In the ecological blink of an eye since then, they have spread throughout the country to become the most significant predator of small forest birds, invertebrates and reptiles.