1 Farmer-participatory research approaches towards agriculture-aquaculture integration for sustainable management of natural resources 1,2 Mark Prein, Clive Lightfoot 3 and Roger S.V. Pullin International Center for Living Aquatic Resources Management, MCPO Box 2631, 0718 Makati, Metro Manila, Philippines Summary Aquaculture in developing countries can improve the sustainability of small-scale farms provided that it is fully integrated with other enterprises and household activities so as to allow farm families and communities to manage their natural resources effectively and sustainably. This requires the consideration of pond management and fish husbandry as means to a variety of ends (water storage, soil conservation and fertility, integrated pest management, etc.), not just production of fish. This approach to Integrated Resources Management (IRM) is described with reference to the Inland Aquatic Resources Systems Program of ICLARM. The benefits of this approach are illustrated with examples from Southeast Asia and Africa. The research methods and remaining research challenges are also described. I. Introduction Recycling of a farm’s biological resources, wastes and by-products can husband natural resources and improve productivity and incomes. It is well known that soil fertility is improved when organic matter is returned to the soil. Farmers estimate that compost materials can replace basal applications of the elements nitrogen, phosphorous and potassium to reduce fertiliser costs by up to 50%. Recycling is a bigger part of the farm economy than has often been appreciated. Indeed, when recycling flows are given cash values, the gross incomes of farmers increase dramatically; for example the value of all recycled materials can be up to 40% of gross farm income. High value flows are exemplified by the use of rice grain to feed chickens, or snails to feed chickens, ducks and fish. High volume but lower value flows are exemplified by those for rice straw, which is utilised both as livestock feed and compost material, and napier grass which is used as feed for cows, water buffalo and goats. The water buffalo, like most livestock, contribute to recycling by eating grass and crop residues and producing manure (organic fertiliser) for the crops. Moreover, the water buffalo is used as a draft animal and also produces milk and meat. Ducks produce eggs, meat and droppings. And fish convert crop, livestock and household wastes into high quality protein and nutrient rich pond mud. Pond mud is so rich that it can replace fertilizer completely in small vegetable gardens. 1 A previous version of this paper was presented at the ILRI Consultation on Livestock Research Priorities in South East Asia, 10-13 May 1995, IRRI, Los Baños, Philippines. 2 ICLARM Contribution No. 1158. 3 Present address: Information Centre for Low External Input and Sustainable Agriculture, PO Box 64, NL-3830 AB Leusden, The Netherlands.