Rodents don’t all behave the same way. They don’t live in the same places, aren’t attracted to the same foods, and they’re definitely not the same size.

So if you've spotted a rodent (or two) around your house, garden or shed, the first step to success is knowing exactly who you're dealing with.

We’re usually up against three main rodent types. Each has its own habits, quirks, and favourite nesting spots. Meet the usual suspects:

1. Ship rat (aka roof rat or black rat)

Ship rats are the most common rat in urban New Zealand.

They’re usually 12–17cm long (body length) and weigh up to 300g. Their fur ranges from black to light brown, and their underside is typically lighter than the rest of their body.

They’re excellent climbers and mainly arboreal, meaning they prefer to live in trees. In urban areas, they’ll often move indoors and nest in roof cavities, ceilings, and walls. If you hear scratching above your head at night, you may have ship rats. They often access homes by climbing trees onto roofs and squeezing through small gaps.

What do they feed on? They’ll go for rubbish, compost, pet food in urban areas. Seeds, berries, insects, birds in the bush. Crops, feed, wiring on farm land.

Tip: Remove accessible food sources and trim back overhanging trees. If they can’t access food or entry points easily, they’re less likely to stick around.

2. Norway rat (aka brown rat or water rat)

Norway rats are much larger than ship rats. Including the tail, they can reach up to 50cm long and weigh up to 500g.

They have coarse brown or dark grey fur and a lighter underside.

Unlike ship rats, Norway rats prefer to stay at ground level. They build burrows in soil, under decks, sheds, and foundations. If you notice holes around 5–6 cm wide in the ground around your property, or holes under fences, you could have Norway rats.

They’re strong swimmers too, which is why they’re often called “water rats.” You’ll commonly find them near rivers, lakes, drains, and even swimming pools.

DOC has found they are commensal, meaning they are strongly associated with human activity, and they thrive in urban environments. They’re highly adaptable and found across much of New Zealand.

Norway rats have a home range of up to 900 metres. That means your neighbour’s compost heap might be feeding the rats visiting your garden.

Tip: Look beyond your property. Effective rat control often works best when neighbours are involved.

3. House mice

Small but mighty. House mice are much smaller than rats, typically 7–10cm long (body length) and weighing only 10–25g.

They have:

• Light brown or grey fur

• Large ears relative to their body

• Small droppings (about the size of rice grains)

Mice have a much smaller home range, often only 5–30 metres. That means if you’ve got mice, they’re probably living very close to where you’re seeing them.

They love wall cavities, cupboards, garages, sheds, stored boxes...

Unlike rats, mice are curious and more likely to investigate new objects quickly. But they also reproduce extremely fast, so early action is key.

Tip: Because mice stay close to home, finding their nest area is critical for effective trap placement.

Still not sure who the culprit is?

If you’ve found droppings, check out our article: Know Your Predators – Poo Edition

If you’ve noticed chew or run marks, deploy some trap location cards and compare nibble patterns against: Know Your Predators – Nibble Edition

Now you know who’s moved in. What next?

Where you’ve seen a rodent isn’t necessarily where they’ll feel safest stopping to investigate a trap.

The key is identifying where they’re most comfortable feeding.

To help find that magic spot, we’ve developed trap location cards, included in our A24 Trap kits. These chew cards can be baited with whatever lure you have on hand, peanut butter, Nutella, or similar.

Place them around your property. Once you see nibble activity, you’ve found your ideal trap location.

To increase your chances of success:

• Remove competitive food sources (pet food, seeds etc…)

• Secure rubbish and compost

• Seal entry points

• Follow our success tips

Still unsure which trap is right for you? Take our trap quiz