The aim of this study is to describe the relationship between fishermen and middlemen by analyzing the practice of Fresh Fish (FF) trade and comparing it to Processed Fish (PF) trade. Lake Chad has been and still is a very important fish supply center in the semiarid zone of West Africa, and PF trade has catered neighboring countries since old times. From the early 1970s, however, FF trade increased dramatically. The main reasons for this were the change of fish fauna of Lake Chad by droughts occurred between 1970 and 1994 and the introduction of modern transit and cold storage technologies. In the relationship between fishermen and middlemen of PF trade, it can be observed PCR characterized by the reciprocal agreement and the exclusivity contract; but this is not the case in FF trade. FF fishermen engage in the migrant fishing with low cost fishing gears, targeting low price but quantitatively stable fish species, and exchanging the catchment immediately by cash according to the market price. Fishermen employ the certain fishery and it is the livelihood and cash earning strategies to reduce the fluctuation risk of fish catches in uncertain fishing environments. While the activation of FF trade contributes to the livelihood of small-capital fishermen live around Lake Chad, it also poses a threat of resource depletion because of the fishing pressure increased. To seek the sustainable use and the appropriate management of the fishery stock is getting an important issue of the fishery in Lake Chad.

Since 1995, we have been researching the "Wild Yam Question," that is, whether or not human beings could live without agricultural products in tropical rainforests. We conducted surveys of the distribution and reserves of yam and yam-like plants and observational surveys of 3 controlled foraging trips, during which the cooperators of the Baka hunter-gatherers could use no agricultural products, in the Ndongo area and showed the possibility human beings be able to live without agricultural products and the high reliability of yam tubers to a foraging life in the tropical rainforest of southeastern Cameroon. But there still remain some issues to be examined. Our 2 controlled foraging trips were done in a forest area which local people rarely visited and was likely to be rich in wild food resources, and the third trip was done in a forest area which they often entered to set snares and was likely to be poor in wild food resources. How does the foraging life style differ between these 2 types of forest? Furthermore, in the previous 2 controlled foraging trips the Baka cooperators used wire-snares, but did not use them on the latest trip as such durable and labor-saving wire-snares would not have been available to Stone Age hunter-gatherers. What difference does the presence or absence of wire-snares make to the foraging life style in tropical rainforests? Based on this survey of a controlled foraging trip in a communal forest which local people communally managed and exploited, we demonstrated that (1) supplying a comparable amount of food to that in remote forests rich in wild food resources, yam tubers remained a staple food for forest foragers even in a communal forest, (2) the present Baka could obtain few game animals without the use of wire snares in the communal forest, (3) game animals, like yam tubers, are a critical food for the foraging lifestyle in southeastern Cameroon forests as their scarcity has a notable impact not only on the hunter-gatherers nutritional intake but also on their emotional state.