The purpose of this paper is to create and discuss a measure of water hyacinth abundance in Lake Victoria. Water hyacinths have dramatic effects on other activities such as fisheries. However, understanding their spread and effects is hampered by the lack of reliable information.

As environmental goods such as fuelwood and fodder become more scarce, rural households in developing countries spend more time in their collection. It has been suggested that as a result households may reallocate labor away from own-farm agricultural production.