Subsistence and Commercial Activities. Traditionally the Iatmul were mainly hunters and gatherers, depending on fish and sago, with horticulture a secondary activity as the gardens on riverbanks are often inundated before the root crops (yams and taro) are ripe. Bananas and coconuts are regularly consumed. The hunting of game (wild pigs, crocodiles, and, rarely, cassowaries) is practiced only irregularly. Fishing is mainly women's work, using hooks, nets, and traps; when men fish they use spears. Among women there is an informal system of redistribution that provides fish to women who are unable to leave their houses because of illness, menstruation, childbirth, or old age. Although most Iatmul villages have sago stands, they have never been productive enough to guarantee a continuous supply. Therefore, Iatmul depend on sago produced by Sawos villages to the north and by some Sepik Hills villages to the south. Every few days Iatmul women transport fresh and smoked fish in their canoes to market places, most of which are located in Sawos territory. There, they barter fish for sago with women from bush villages. The women's trading expeditions take a full day and are carried out mostly by elderly women who are commissioned by younger women to do the bartering for them.
Industrial Arts and Trade. Most Iatmul villages specialize in the production of different kinds of goods that are used for trading. Aibom is well known for pottery, which traditionally was traded for sago throughout the Iatmul area; today it is sold for money as well. Chambri, a non-latmul border village to the south, specializes in firmly plaited mosquito bags manufactured by women. In all Sepik villages, where mosquitoes and malaria are endemic, these bags are used by entire families sleeping in them communally. Tambunum is renowned for its plaited bags, also produced by women, with various Colored patterns. Iatmul carvings are among the most artistic in New Guinea. Men began producing them in large quantities when they found early travelers and art dealers interested in them. Anthropologists argue that Iatmul attained superiority and control over their neighbors by being a "cultural factory," producing sacred artifacts, spells, and knowledge and then exporting them. However, no reliable information confirming this can be found, except for an exchange of ritual items that must have taken place in both directions as indicated by Abelam paintings collected by early German explorers in Iatmul villages. As far as can be determined, irregular trading expeditions took place up southern tributaries and vice versa, with paint, edible earth, and bark used for medicinal purposes imported from these areas. Shell rings, turtleshell ornaments, and other valuables arrived in the Middle Sepik through the Abelam and Sawos regions and also from the upper regions of the Sepik River. Stone blades as well as pearlshells came from the highlands to the south.
Division of Labor. Subsistence activities, mainly the gathering of fish and sago, are carried out by women. Men make almost all implements used for subsistence (canoes, paddles, and tools for sago production) except fish traps, nets, and bags. Men build the houses and are also the ritual specialists.
Land Tenure. Lagoons and the open river are considered the property of the villages. Clans own rights to specific fishing and gathering locales. Garden land is also owned by clans or lineages and is allotted among the male members of the clan at the end of each flood season.