Polynesian rat, Pacific rat, Maori rat, kiore
The Polynesian rat is known as the Kiore in New Zealand, where it is an important cultural animal to the Maori people.
Body plus head length: 110-130mm. Tail length: 120 to 150mm. Weight: usually 60-80g, but animals of up to 180g have been found. The animals on small islands, such as the Hawaiian islands, are smaller, weighing only 37 to 39g.
The Polynesian rat is similar in appearance to the black, or ship, rat (Rattus rattus), but smaller. Its fur is brown-grey on the back, with the underside a light grey. The tail is uniformly dark. Females have four pairs of teats.
They are found from Bangladesh to Vietnam, throughout the East Indies and on many Pacific islands including Easter Island, Hawaii and New Zealand. Their distribution is so wide because they have been introduced both accidentally and deliberately by people to many of these places.
They are found in a wide variety of habitats, including grasslands, shrublands, scrub and various types of forest. In Southeast Asia the Polynesian rat has a very close association with people, inhabiting houses and rice fields.
Polynesian rats are omnivorous, eating insects, centipedes, spiders, worms, snails, fruit, seeds, leaves and roots. Sometimes they eat lizards and birds or strip bark from saplings. They are considered pests in many places, as they feed on sugar cane, coconuts, cocoa and other crops.
Polynesian rats are nocturnal, starting to become active around dusk or just after. They are agile climbers and sometimes nest and feed in trees. Each rat has a small home range of up to 280m diameter. Females avoid each other in the breeding season.
Females are capable of having up to 13 litters per year, but 1 to 3 litters is normal for wild populations. Gestation period is 19 to 30 days. Litters are normally born in the summer. There are 2 to 5 offspring per litter, and these are weaned when 2 to 3 weeks old.
Polynesian rats are not listed by the IUCN.
Polynesian rats carry various diseases that are transmittable to humans, including plague and leptospirosis.