Fixed investments in aquaculture farms (land, ponds/tanks, and equipment) are listed in Table 3. A small-scale prawn farm with a single 1-acre pond is estimated to need approximately $10,500 for these costs (excluding substrates).
Sharing resources among several ponds reduces the per-acre fixed cost (e.g., $8,500 for a farm with two 1-acre ponds, $7,891 for a farm with three 1-acre ponds, etc.).
Posadas (2004) estimated that the fixed cost of operating 25 2-acre ponds would be about $5,000 per acre (using Mississippi data).
Fixed costs:occur during start-up and during pond and equipment renovation or replacement. However, they can be evaluated on an annual basis by depreciating equipment and calculating the interest associated with the fixed investment.
To calculate depreciation one must know the initial value, salvage value, and lifespan of each depreciable asset.
We assumed that land was valued at $1,000 per acre and did not depreciate, and that the salvage values for a 1-acre pond and equipment were $3,000 and $0, respectively.
Hence, the fixed investment values in Table 3 result in a total annual fixed cost, for a small-scale Kentucky prawn farm, of $1,699 without substrate and $2,360 with substrate.
Variable costs:
Variable costs include the cost of seed, feed or fertilizer, energy (electricity, gasoline or diesel), chemicals, labor and management, telephone, advertising, legal permits, maintenance, etc.
Table 4 lists approximate variable costs, based on current data from Kentucky and Mississippi, for three different production systems. Seed and feed costs increase as the intensity of production increases, while other costs remain fairly stable.
The stocking cost depends on both the seed price and the stocking density. Producers generally stock 30- to 60-day-old nursed, juvenile prawn; a few stock post-larvae at higher densities, after accounting for a 30 to 50 percent post-stocking mortality.
Recently the price of juveniles has ranged from $0.07 to $0.12 per head in Kentucky. This price is dependent on juvenile age, whether or not the juveniles were size graded (research has shown that at higher densities, stocking juveniles of uniform size results in more uniformly sized adult prawn), and the hauling distance between the nursery and the farm.
Research also has shown that older juveniles (e.g., 60-dayold animals) have a higher survival rate than younger juveniles (e.g., 30-day-old animals). In 2004, juvenile prices in Mississippi were approximately $0.045 per head (Posadas, 2004).
Table 4 shows that the stocking cost is 20 to 40 percent of variable cost, so the price of juveniles will have a significant effect on total cost. Feeding cost is proportionately less than stocking cost. Feeding rates for extensive and semiintensive operations usually follow the feed tables recommended by D’Abramo and Brunson (1996) (see SRAC publication # 484 for additional details).
The feeding rates for intensively stocked ponds, found in Tidwell et al. (2002), are higher than those in D’Abramo and Brunson (1996), not exceeding 60 to 75 pounds per acre per day.
The labor and management cost was $6.00 per hour for a 1-acre pond in Kentucky. Labor cost in Mississippi was substantially lower because there were 50 acres in production, resulting in economies of scale. In most small scale farming, labor and management are provided by the farm family and are not cash costs.
However, labor and management are opportunity costs and should not be ignored in computing total cost. The chemicals needed for prawn farming typically include agricultural lime, pond fertilizers and rotenone. Legal fees typically involve purchasing an annual propagation permit from a state government agency for fish and wildlife.
Marketing costs, which include advertising the harvest date and farm location in the local media, apply primarily to producers who sell prawns directly to consumers. Advertising costs for wholesale sales would be minimal.
Information Sourced From:
Southern Regional Aquaculture Centre
