2009 -
Economic Forecasting and Policy Analysis Model for Catfish (US-Catfish Model)
Madan M. Dey, Kehar Singh, and Carole R. Engle

The Aquaculture/Fisheries Center of the Type University of Arkansas at Pine Bluff has constructed a user-friendly model for the U.S. catfish market (known as US-Catfish Model) for analyzing recent structural changes in the catfish industry and for comparative analysis of policy options. The simulations of the model show that a decrease in feed price benefits the U.S. farm-raised catfish industry. The decrease in feed price reduces the cost of production, which in turn increases the profitability of farmers, and hence increases supply. This reduces the domestic price of U.S. farm-raised catfish, and increases the quantity demanded for the same. An increase in advertisement expenditure of The Catfish Institute benefits U.S. farm-raised catfish marginally, but reduces imports significantly. Tariffs on imports increase U.S. wholesale prices by $0.07/lb and farm prices by $0.03/lb. An increase in tariff levels on basa/tra imported from Vietnam may enhance importation of channel catfish from China without substantially increasing the demand for U.S. farm-raised catfish. Decrease in U.S. per capita income would have a negative impact on the catfish industry as a whole, with greater negative impact on imported channel catfish. The results of the model show that “country of origin leveling” benefits U.S. farm-raised catfish marginally, but reduces channel catfish imports significantly.

Economics of Year-Round Production of Hybrid Striped Bass: Cost Analysis of Production in Ponds and Tanks
Patty Eklund, Carole Engle, and Gerald Ludwig

Year-round production of hybrid striped bass fingerlings would allow foodfish growers to sell product throughout the year, improving consistency of market supply and cash flow for the farm. However, pond production of fingerlings in late summer is hampered by poor survival. Tank culture methods have been developed to produce hybrid striped fingerlings indoors throughout the year, but the associated costs have not been estimated. Economic engineering techniques were used to estimate production costs of hybrid striped bass fingerlings in ponds (0.4-ha, 1.2-ha, or 2.4-ha) and tanks (946-L; 2,461-L; or 5,678-L) for production scales of either 50,000; 100,000; 250,000; 500,000; 1,000,000; or 2,000,000 fingerlings per year. Results demonstrated economies of scale in terms of the volume of production and of size of the production unit. Overall, pond production was less expensive per 1,000 fingerlings than tank production, even when accounting for an increased number of production cycles in tanks as compared to ponds.  

Aquatic Weed Problems in Arkansas
Patty Eklund and Carole Engle

Aquatic plant management is of great importance to natural resource managers, pond owners, and fish producers throughout the United States. Personal interviews were conducted of fisheries biologists of the U.S. Army Corps of Engineers and the Arkansas Game and Fish Commission to determine what species are currently causing problems and the management techniques used for control in Arkansas. Three mail surveys were conducted of AGFC District Fisheries Biologists (AGFC DFB), private farm pond owners, and fish producers in 2007 and 2008. A master list of problematic aquatic plant species was compiled from secondary internet sources (on-line aquatic plant databases, extension plant identification websites), literature review of extension aquatic plant manuals, input from members of the Arkansas ANS Task Force, and results from the USACE personal interview and surveys. A total list of 197 aquatic plant species that are problematic in Arkansas was created, including county and/or waterbody locations, the majority of which were native species. Forty-one nonnative species were identified, with 11 species being considered nuisance species. Biological control techniques were most commonly used in public water bodies while chemical control techniques were used more often to manage private water bodies. The grass carp (Ctenopharyngodon idella) was the most commonly used biological control agent for the AGFC while the USACE relies on a combination of grass carp and Pakistani flies. Management techniques were aimed primarily at native species for the AGFC and nonnative species for the USACE. Private farm pond owners and fish producers also managed primarily for native emersed and native algal species, respectively. Nonnative aquatic plant species are becoming more of a concern to AGFC DFBs throughout the state, in particular alligatorweed (Alternanthera philoxeroides).   

2008 - 
Feeding versus Fertilization in Baitfish Farming: Which is More Profitable when Feed Prices are High?
Carole Engle, Nathan Stone, and Larry Dorman 

Fish feed prices have increased by about 55% since 2007. Additional increases in fuel and electricity rates, fertilizer prices, and other input costs have continued to increase costs of production. Many farmers have cut back on key operating inputs during these times of high prices. Enterprise budgets for golden shiners were used to calculate the costs associated with different feed prices and yields that are associated with different levels of fertilization and feeding. Yields of baitfish below 450 lb/ac were not profitable at 2007 feed prices; profits increased by $200/acre for every 50-lb increase in baitfish yield. At feed prices of $375/ton and above, baitfish farms must produce yields of 500 lb/acre to be profitable. Switching from feeding to only fertilizing baitfish ponds reduces yields by 200 lb/ac, for a loss of $128,000. The savings from not buying feed compensate for the cost of fertilizer, but not the lost value from lower yields. Farms will lose more money fertilizing and not feeding. It is more economical to feed to produce yields of 500 lb/ac, even at current high feed prices.

Are Hybrid Catfish Fingerlings Worth More Than Channel Catfish Fingerlings?
Ganesh Kumar and Carole Engle  

Production studies that compare production of channel-blue hybrid catfish with various strains of channel catfish provide conflicting results. This study attempted to arrive at a breakeven price for hybrid catfish fingerlings after analyzing data from two experimental and ten commercial ponds that compared hybrid catfish to normal channel catfish and four experimental trials that compared hybrid catfish to NWAC -103 channel catfish foodfish growout. Variables considered included stocking density, length and weight of fingerlings at stocking, survival, feeding rate, and net yield. When compared to normal channel catfish strains, the value of hybrid fingerlings was 0.74 + 0.74 cents/inch/ fingerling more than that of normal catfish strains. When compared to NWAC -103 channel catfish, the hybrid fingerlings had a value that was 0.61 + 1.32 cents/inch/ fingerling greater than the price of NWAC -103 fingerlings. The coefficients of variation were high reflecting the wide variation in results of production studies involving hybrid catfish. However, at a hybrid fingerling cost of 1.89 cents/inch, production costs ($/lb) of normal and NWAC -103 foodfish were $0.011-$0.018/lb lower than that of hybrid foodfish. Farmers should carefully evaluate production performance, costs, and the value of hybrid fingerlings under their own farming conditions.

The Economic Trade-offs between Stocking Fingerlings and Stockers: A Mixed Integer Multi-stage Programming Approach.
Carole Engle, Ganesh Kumar and David Bouras

A mixed integer-programming model of catfish growout was developed that included seven fingerling, six stocker, and eight foodfish production activities as well as options to purchase and sell fingerlings, stockers, and foodfish. Results showed that profits are maximized on farms of 102 ha and larger by adopting a three-phase production system that includes a stocker phase. On farms smaller than 102 ha, profits are maximized by understocking 17.5-cm fingerlings in multiple-batch. The choice of stocking fingerlings or stockers depended on the efficiency of the stocker production phase; at stocker FCRs of 2.4 or above or survivals less than 40%, stocking fingerlings in multiple-batch was more profitable than the three phase system with stockers. Additional research is needed to develop farm-level datasets of the variability in key stocker production parameters to expand this model to explicitly evaluate the effect of risk on the optimal management strategy.

Effects of Feeding Frequency on Multiple-batch Channel Catfish Ictalurus punctatus Production and Costs When Understocked with Large Stockers
Adam S. Nanninga and Carole R. Engle

Increased prices of feed, the greatest component of production costs, have forced some catfish, Ictalurus punctatus, farmers to feed less often to reduce expenditures. This study evaluated the effects of three feeding frequencies (every day ED, every other day EOD, or every third day E3D) when large stockers (69 + 2 g) were under-stocked with carryover fish (>350 g) in multiple-batch catfish production. Twelve 0.04-ha earthen ponds were stocked with 11,115 stockers/ha (69 + 2 g) and 2,240 kg/ha of carryover fish (400 + 10 g) on March 15, 2006 , with four replicates per treatment. Ponds were harvested completely 9-11 October 2006. Gross and net yield increased significantly (P < 0.05) with increased feeding frequency, and total feed fed was greatest for the ED feeding treatment. Growth of stockers decreased significantly as feeding frequency decreased. In this study, growth of carryover fish decreased when fed EOD as compared to ED feeding. Dressout yields of market-sized fish were significantly lower when fish were fed E3D. The partial budget showed a loss of -$896/ha for switching from every day feeding to every other day feeding and a loss of -$2,367/ha for switching from every day feeding to every third day feeding (at a feed price of $260/MT). ED feeding continued to be more profitable up to a feed price of $413/MT.

Measuring Feed Intake For Channel Catfish Ictalurus punctatus During Cool Weather
Adam S. Nanninga and Carole Engle

Channel catfish Ictalurus punctatus fed based on standard winter feeding recommendations lost weight in ponds during winter feeding studies. The objective of this study was to quantify feed consumption over the winter. Six concrete vats with a volume of 5 m³ were stocked in October 2007 with sub-market size fish (mean weight 0.25 kg) and market size fish (mean weight 0.72 kg).  Water was supplied by a pump on the bottom of an adjacent pond at 10.6 l/min.  Feed (32% protein full-sink pellet) was offered daily in feeding trays at a weight of 2% of total body weight of fish every afternoon.  After 15 minutes, trays were pulled up and remaining pellets were counted.  All vats were harvested 16 March 2008. Channel catfish consumed from 0.1% to 0.7% of their body weight daily over the winter when offered feed every day.  While catfish ate more at higher water temperatures, they continued to eat at temperatures as low as 7^oC. Compared to standard winter feeding recommendations, daily feed consumed by catfish was slightly (0.2 - 0.3%) less than the recommended daily percent of body weight to feed (at temperatures > 10 C).  However, the recommended frequency of feeding resulted in weekly recommended feed quantities lower (1.3% - 1.6%) than actual quantities of feed consumed by catfish.

Testing Feed Response Methods of Inventory Estimation For Channel Catfish (Ictalurus punctatus) Production
Pratheesh Omana Sudhakaran*, David Heikes, Carole Engle

Accurate and cost-effective inventory estimation of multiple-batch catfish crops would improve financial and production management. Several inventory estimation methods used by industry consultants and advisors are based on feeding response by fish. Datasets from experimental trials of catfish production in both single and multiple batch systems at various densities were used to estimate and compare the variation in feeding rates.  A coefficient of variation (CV) of quantity of feed fed per treatment was calculated for each week for each pond within three temperature ranges. Analysis of variance (ANOVA) was used to compare CVs calculated using daily feed, two-day means, three-day means and four-day means for each temperature range, for each stocking density and feeding treatment, for both single and multiple batch. Stocking density and temperature had no significant effect on variation of feeding rates in either single or multiple batch production. However, in single batch production, the four-day average of daily feed showed a significantly lower CV (17%) than daily feed (mean CV= 38%), two-day means (mean CV= 27%) or three-day means (mean CV= 24%). In multiple batch production, the three-day average of daily feed had a significantly lower CV (24%) compared to the daily feed (mean CV= 49%) and 2-day average (mean CV= 34%) but was not significantly different from the four-day average (mean CV= 23%).

Does Harvesting And Grading Catfish More Frequently Improve Overall Production Of Catfish?
Pratheesh Omana, Brent Southworth, and Carole Engle

Periodic grading and harvesting of fish increases production in some types of aquaculture by removing larger sizes of fish repeatedly throughout the growing season.  This reduces overall biomass and may allow smaller fish to obtain faster growth.  The objectives of the study were:  1) to determine the effect on production performance of repeated grading and harvesting larger sizes of fish throughout a 2-year growing season, using the traditional live car and UAPB grader; and 2) to determine whether more frequent harvesting and grading with the UAPB grader results in better growth and greater harvested yields of catfish.  Two two-year pond studies were conducted.  The first study (2005-2006) was designed to compare fish production over 2 years when graded and harvested with a standard live car as compared to the UAPB grader.  The second study (2007-2008) compared the effects of harvesting either 2, 3, 4, or 5 times a year on growth and yields of catfish.  Both studies were stocked initially with 5-inch fingerlings stocked at 6,000/ac and 1.0 lb carryover fish stocked at 2,000 fish/ac; all ponds were restocked with 5-inch fingerlings (6,000/ac) in the spring of the second year.  In the first study, more efficient grading (14% fewer under-sized fish sent to processing plant with the UAPB grader) resulted in faster growth of fingerling and carryover fish.    More frequent grading and harvesting removed market-size fish faster and prevented carryover fish from becoming out-of-size.

Evaluation Of Multiple-Batch Channel Catfish Ictalurus punctatus Production Fed Four Recently-Developed Commercial Diets
Neil Pugliese*, David Heikes, Carole Engle, Brian Bosworth

Feed mills adopted new feed formulations in 2008 in response to record high feed prices.  This study compared survival, growth, FCR and net yield of four recently developed commercially available channel catfish diets in a multiple-batch production scenario.  Sixteen 0.1-ha ponds were stocked 8 May 2008 with 14,388 fingerlings/ha (12.5 cm) and 4,308 head/ha (350 g) of carryover fish.  The feeds used in this study were: 1) 32% corn gluten feed, 2) 32% premium feed, 3) 32% standard feed, and 4) 24% premium feed.  Each of the feed treatments was assigned randomly to four ponds.  At harvest (23-26 September 2008), the net yield of carryover fish fed varied significantly with the diet fed with the greatest yield from the 32% premium diet followed in descending order by the 32% standard, the 32% corn gluten, and the 24% premium diet.  The 32% premium and 32% standard feed treatments had similar FCR’s that were significantly lower than the FCR’s of the 32% corn gluten feed and the 24% premium feed.  There was no difference in shank fillet yield among treatments but the catfish fed 32% corn gluten feed had significantly less visceral fat.  A partial budget analysis compared switching to the 32% standard or 32% corn gluten feed from 32% premium.  The higher yield from 32% premium feed more than offset its higher cost.  It was more profitable to feed the more expensive 32% premium feed.