was much earlier than the accepted dates for Polynesian migrations to New Zealand, this finding has been challenged by later research showing the rat was introduced to both the country's main islands around A.D. 1280. Behaviour Polynesian rats are nocturnal like most rodents, and are adept climbers, often nesting in trees. In winter, when food is scarce, they commonly strip bark for consumption and satisfy themselves with plant stems. They have common rat characteristics regarding reproduction: polyestrous, with gestations of 21–24 days, litter size affected by food and other resources (6–11 pups), weaning takes around another month at 28 days. They diverge only in that they do not breed year round, instead being restricted to spring and summer. Diet R. exulans is an omnivorous species, eating seeds, fruit, leaves, bark, insects, earthworms, spiders, lizards, and avian eggs and hatchlings. Polynesian rats have been observed to often take pieces of food back to a safe place to properly shell a seed or otherwise prepare certain foods. This not only protects them from predators, but also from rain and other rats. These "husking stations" are often found among trees, near the roots, in fissures of the trunk, and even in the top branches. In New Zealand, for instance, such stations are found under rock piles and fronds shed by nikau palms. Rat control and bird conservation New Zealand In New Zealand and its offshore islands, many bird species evolved in the absence of terrestrial mammalian predators, so developed no behavioral defenses to rats. The introduction by the Māori of the Polynesian rat into New Zealand resulted in the eradication of several species of terrestrial and small seabirds. Subsequent elimination of rats from islands has resulted in substantial increases in populations of certain seabirds and endemic terrestrial birds, as well as species of insects such as the Little Barrier Island giant wētā. As part of its program to restore these populations, such as the critically endangered kākāpō, the New Zealand Department of Conservation undertakes programs to eliminate the Polynesian rat on most offshore islands in its jurisdiction, and other conservation groups have adopted similar programs in other reserves seeking to be predator- and rat-free. However, two islands in the Hen and Chickens group, Mauitaha and Araara, have now been set aside as sanctuaries for the Polynesian rat. Rest of the Pacific NZAID has funded rat eradication programs in the Phoenix Islands of Kiribati