THE EFFECT OF INCOME ON THE EXTRACTION OF NON-TIMBER TROPICAL FOREST PRODUCTS - MODEL, HYPOTHESES, AND PRELIMINARY FINDINGS FROM THE SUMU INDIANS OF NICARAGUA

We use microeconomic theory to frame hypotheses about the effects of i ncome on the use of non-timber rain forest products. We hypothesize th at an increase in income: (a) encourages foraging specialization resul ting in the extraction of fewer goods; (b) increases the share of hous ehold income from occupations besides foraging; (c) produces a yearly value from the extraction of nontimber forest goods of about $50 per h ectare; and (d) produces depletion of forest goods entering commercial channels and sustainable extraction of goods facing cheaper industria l substitutes. To examine these hypotheses we present worldwide ethnog raphic information and preliminary findings from field work carried ou t among the Sumu Indians of Nicaragua. Field work suggests that higher income produces: (a) foraging specialization with animals rather than with plants; (b) a decline in the economic importance of forest goods in household income; (c) and a rise in the value of non-timber goods removed from the forest to about $35/ha/year. We did not have time to test hypothesis ''d.''