The food resources available to the pre-European Maori were both scanty and scattered, and each hapu (sub-tribe) was therefore highly mobile within its territory. To safeguard claims to resources - for Maori society was fiercely competitive, and food, which was obtained only by sustained effort, was in consequence its natural 'currency' - the hapu must constantly maintain them, and transmit a record of their usage to their descendants. Claims to territory were expressed by both social and economic activities carried out within it, and only a person who could prove an intimate physical association between the land and every ancestor on his genealogy was entitled to use hapu resources. With the arrival early in the nineteenth century of Europeans, outlets for competition multiplied. Nga Puhi, who raided their neighbours for labour to grow food for the early shipping, acquired great mana from their wealth in guns and in captives. Everywhere they were emulated by other tribes; notably by Te Rauparaha’s Ngati Toa, who migrated from Kawhia to Cook Strait to establish a stranglehold on the trade provided by the shore whalers. The Ngati Toa allies - Ngati Raukawa, Ati Awa - who assisted in the conquest of the South - resented Te Rauparaha’s monopoly of the new wealth, and resented even more his attempts after 1839 to take payment for the lands from the settlers and Government for his imagined claims by conquest to their lands. The arrival of pakeha land purchasers heralded a rush to sell land to substantiate claims (after the traditional manner) by publicly receiving payment for them. The first 'sales', of course, made by a people who knew nothing of land transfer or written deeds, were unwitting; Te Rauparaha and Te Wharepouri of Port Nicholson later stood by them, rather than compromise their right to have taken payment in the first place. The Ati Awa went home to Taranaki to embark on a series of deliberate sales, competing against one another for recognition of their claims in the form of payment from Land Purchase officers. Ihaia Te Kirikumara was one chief who spared nothing in his attempts to take payment for land he claimed at Waitara, and in 1860 he watched in triumph as British troops ousted his opponent Wi Kingi.