This study utilizes data from two fingerling production studies and one growout study to develop a data set of costs of producing 3,5,6, and 7 inch fingerlings with and without thinning. A third study developed estimates of key production parameters of catfish growout ponds when carryover fish were understocked with 3,5, or 7-inch fingerlings. Enterprise budgets and risk analyses were conducted for each study. These data will be used as coefficients in a multi-year dynamic linear programming model to explore the trade-offs associated with allocating pond space to producing and understocking different sizes of fingerlings.

2. Estimating Costs of Producing Stocker Catfish on Growout Farms

This study will follow the fingerling production studies and develop similar types of data to be incorporated into the mathematical programming model.

3. Economic Interactions Between Stocking and Feeding Practices in Intensive Catfish Production

This study estimated a Just-Pope production function to explore the economic interactions between stocking and feeding practices. It demonstrated that, although maximum yield may be obtained at higher stocking densities, the profit-maximizing stocking rate is between 6,000- 7,000 fingerlings/acre.

4. Farm-Level Economic Effects of Cormorant Predation on Farm-Raised Catfish

Enterprise budget analysis was used to compare net returns for farms with and without losses due to bird predation. Predation by cormorants was demonstrated to decrease yields by as much as 20% that results in negative returns on a farm that would have had positive net returns without cormorant predation. Additional 'work will utilize a two-year dynamic programming model to vary levels of bird pressure on catfish farms to evaluate relative effects on farm income and management strategies.

5. Determining the Profit-Maximizing Pond Size on Levee-Style Catfish Farms

A catfish production function was estimated using 1997 USDA survey data of U.S. catfish producers. A primal approach was employed to derive a net income function from the estimated production function, which was then used to estimate the profit-maximizing pond size. Results indicated that farms with larger ponds had greater variability of yield. The optimal pond size decreased as the number of ponds likely to be off-flavor increased. However, optimal pond size increased with farm size. Larger farms, with space for a greater number of ponds, could take more advantage of the lower costs associated with building slightly larger ponds.

6. Estimating the Economic Returns to the PD/A CRSP Research Investment in Thailand

Time-series secondary data on industry changes and technology transfer efforts will be used to measure aggregate changes in the supply of tilapia in Thailand. A survey of tilapia farmers who participated in on-farm trials of CRSP-developed technologies and those who did not participate will provide a basis to evaluate farm-level impacts of the adoption of CRSP
research technologies.

7. Development of Central American Markets for Tilapia Produced in the Region

Surveys were conducted of restaurants, supermarkets, and fish markets in all major urban and 8 small towns in Honduras that were based on a census of supermarkets and fish market vendors and a random sample of restaurants. Information was collected on product forms and sizes of fish species currently sold, current prices and volumes sold, current supply channels for different fish species and product forms,-and buyer attitudes towards farm-raised fish. Similar surveys will be conducted this summer in Nicaragua. Logit analyses will be conducted to determine those factors with the greatest effect on attitudes and preferences towards farm-raised tilapia and the likelihood that intermediate buyers will begin to purchase farm-raised tilapia products. This study will provide guidelines for development of a domestic market for tilapia in Honduras and in Nicaragua that would provide greater stability to the fledgling tilapia industry in the region.

8. Optimizing Stocking and Management Practices on Shrimp Farms in Honduras

A Target MOT AD linear programming model was developed to determine optimal stocking densities, length of production cycle, and stocking months to maximize net farm income on shrimp farms in Honduras. A 3-yr data set of pond production records from several farms was used to formulate the model. The model indicated that stocking at intermediate rates and adoption of new, low-water exchange rate technologies generated higher profits than the alternatives considered.

9. Fingerling Cost Budgets

.Two sets of budgets have been developed for production strategies with and without thinning. The budgets are developed for the production of 3, 4, 5, 6, and 7, inch fingerlings for both types of management strategies. These budgets should be available from the U APB Cooperative Extension Program in May.

10. Watershed Pond Catfish Production Budgets

A budget was developed for the production of foodsize catfish in watershed ponds in Arkansas. The budget unit was a 10-acre pond that was part of an 80-acre growout operation. This Fact Sheet should be available from the UAPB Cooperative Extension Program in April.