Environmental Assessment of Channel Catfish Ictalurus punctatus Farming in Alabama

An environmental assessment was made of Alabama channel catfish Ictalurus punctatus farming which is concentrated in the west‐central region of the state. There are about 10,000 ha of production ponds with 10.7% of the area for fry and fingerlings and 89.3% for food fish. Food fish production was about 40,800 tons in 1997. Watershed ponds filled by rainfall and runoff make up 76% of total pond area. Water levels in many of these ponds are maintained in dry weather with well water. The other ponds are embankment ponds supplied by well water. Harvest is primarily by seine‐through procedures and ponds are not drained frequently. The main points related to Alabama catfish farming and environment issues are as follows: 1) catfish farming in Alabama is conservative of water, and excluding storm overflow, about two pond volumes are intentionally discharged from each pond in 15 yr; 2) overflow from ponds following rains occurs mostly in winter and early spring when pond water quality is good and stream discharge volume is high; 3) total suspended solids concentrations in pond effluents were high, and the main sources of total suspended solids were erosion of embankments, pond bottoms, and discharge ditches; 4) concentrations of nitrogen and phosphorus in effluents were not high, but annual effluent loads of these two nutrients were greater than for typical row crops in Alabama; 5) ground water use by the industry is about 86,000 m³/d, but seepage from ponds returns water to aquifers; 6) there is little use of medicated feeds; 7) copper sulfate is used to control blue‐green algae and off‐flavor in ponds, but copper is rapidly lost from pond water; 8) although sodium chloride is applied to ponds to control nitrite toxicity, stream or ground water salinization has not resulted from this practice; 9) fertilizers are applied two or three times annually to fry and fingerling ponds and occasionally to grow‐out ponds; 10) hydrated lime is applied occasionally at 50 to 100 kg/ha but this does not cause high pH in pond waters or effluents; 11) accumulated sediment removed from pond bottoms is used to repair embankments and not discarded outside ponds; 12) sampling above and below catfish pond outfalls on eight streams revealed few differences in stream water quality; 13) electricity used for pumping water and mechanical aeration is only 0.90 kW h/kg of production; 14) each metric ton of fish meal used in feeds yields about 10 tons of dressed catfish. Reduction in effluent volume through water reuse and effluent treatment in settling basins or wetlands does not appear feasible on most farms. However, some management practices are recommended for reducing the volume and improving the quality of channel catfish pond effluents.     

Evaluation of a Confinement System for Growout of Channel Catfish Ictalurus punctatus

Rising costs of inputs have created a need to improve catfish production efficiencies. An inexpensive confinement system was evaluated for channel catfish Ictalurus punctatus foodfish production. Barriers were constructed in five 0.1-ha earthen ponds to partition ponds into 1/3 and 2/3 sections. Large fingerling (136 g) catfish were stocked at 11,115 fish/ha in the smaller 1/3 section (shallow end) of the confinement ponds or in open ponds (control). Seining efficiency was significantly greater for the confinement system. Yield and daily growth of food fish were significantly lower and feed conversion ratio higher in the confinement system compared to open ponds. Partial budget analysis showed a net loss of –$313/ha. Additional work is needed to develop inexpensive production systems to capture efficiencies of confinement without decreasing production.     

Economic Impact of Double‐Crested Cormorant,Phalacrocorax auritus,Depredation on Channel Catfish,Ictalurus punctatus,Aquaculture in Mississippi,USA

The Yazoo River Basin of Mississippi, USA, supports the largest concentration of hectares devoted to channel catfish, Ictalurus punctatus, aquaculture production in North America. The Yazoo Basin also supports large numbers of resident, wintering and migrating fish‐eating birds, with the Double‐crested Cormorant, Phalacrocorax auritus, implicated as the most serious depredating species. We used data from aerial surveys of numbers and distribution of cormorants in the Yazoo Basin and on commercial catfish ponds during winters (November–April) 2000–2001 and 2003–2004 to refine estimates of regional economic losses due to cormorant depredation. In both periods, the greatest monthly estimates of cormorant foraging occurred from 1 January to 31 March. Losses in terms of biomass, number, and dollar value were greater for foodfish ponds than fingerling ponds. Monthly weighted estimates of catfish consumed were 1775.3 and 1346.6 m.t. over winters 2000–2001 and 2003–2004, respectively. Total estimated losses for foodfish and fingerling ponds in 2000–2001 were $11.56 and $0.48 million, respectively, and in 2003–2004 were $5.22 and $0.40 million, respectively. Maximum dollar loss occurred during March in 2000–2001 and during February in 2003–2004. In this study, the volatility in variable production costs and nominal sales price, and distribution of cormorants on pond types and regionally were key factors in resulting economic loss estimates.     

Modeling industry-wide sediment oxygen demand and estimation of the contribution of sediment to total respiration in commercial channel catfish ponds

Data collected from 45 commercial channel catfish, Ictalurus punctatus, ponds were used to develop empirical models predicting sediment oxygen demand (SOD). Seven acceptable models were combined with a Monte-Carlo sampling distribution to predict industry-wide sediment oxygen demand (SOD_i). The SOD_i values obtained from the best equation were used in simulations to assess the effect of diurnally varying water column dissolved oxygen (DO) concentrations on SOD and the effect of pond water depth on the contribution of SOD to overall pond respiration. Estimated SOD_i ranged from 62 to 962 mg m⁻² h⁻¹, with a mean of 478 mg m⁻² h⁻¹. There was a 95% probability of mean SOD_i being ≥700 mg m⁻² h⁻¹. The effects of diurnal variation in DO concentration in the water column on expression of SOD was modeled by combining maximum SOD_i, an empirical relationship between DO and SOD, and simulated pond DO concentrations. At DO concentrations >15 mg l⁻¹, diel SOD in catfish ponds exceeded 20 g O₂ m⁻² day⁻¹. But when average diel DO was <4 mg l⁻¹ and the range of DO concentration was 6–8 mg l⁻¹, SOD decreased to 13 g O₂ m⁻² day⁻¹ because DO availability limited the full expression of potential SOD. Respiration totals for sediment (average SOD_i), plankton, and fish respiration were calculated for pond water depths ranging from 0.25 to 4 m. Although whole-pond respiration increases as pond depth increases, the proportion of total respiration represented by sediment decreased from 48 to 10% by increasing water depth over this range. The results of these studies show that SOD is a major component of total pond respiration and that certain management practices can affect the impact of SOD on pond oxygen budgets. Mixing ponds during daylight hours, either mechanically or by orienting ponds for maximum wind fetch, will increase oxygen supply to sediments, thereby allowing maximum expression of SOD and maximum mineralization of sediment organic matter. Given a mixed condition caused by wind or other artificial means, the construction of deeper ponds increases the total mass of DO available for all respiration, causing nighttime DO concentrations to decline at a slower rate, reducing the need for supplemental aeration. Because a pond’s water volume decreases over time from sediment accumulation, annual aeration costs will increase with pond age. Constructing ponds with greater initial depth will therefore reduce long-term cost of aeration, allow more flexible management of pond water budget, and reduce the long-term expense associated with pond reconstruction.     

Principal economic effects of cormorant predation on catfish farms

Substantial economic losses of farmed catfish to fish‐eating birds such as the double‐crested cormorant, Phalacrocorax auritus, continue to be reported on U.S. catfish farms. An economic analysis was conducted of the on‐farm effects of both the increased expenditures to scare fish‐eating birds from catfish farms and of the value of the catfish that were consumed by cormorants. A survey was conducted of U.S. catfish farmers in the Delta region of Mississippi and Arkansas, to obtain farm‐level data on expenditures to scare birds. Estimations of the lost revenue from catfish consumed by cormorants were developed from a concurrent study on cormorant distribution, abundance, and diet in the region. The economic effects of bird predation in terms of both fish consumption and management costs were evaluated across three farm sizes and nine catfish production practices. Catfish farmers spent on average $704/ha ± $394/ha to scare birds, making bird‐scaring costs one of the top five costs of raising catfish. The greatest cost components of scaring birds were manpower (39% of all bird‐scaring costs) and the variable and fixed costs of trucks used to scare birds (34% of all bird‐scaring costs). Losses were greater on hybrid than channel catfish fingerling ponds. Industry‐wide, the value of catfish losses averaged $47.2 million (range of $25.8–$65.4 million). Total direct economic effects (including both the increased costs to scare birds and the revenue lost from fish consumed by cormorants despite bird‐scaring attempts) averaged $64.7 million (ranging from $33.5 to $92.6 million). Profitability improved by 4% to 23% across the farm size/production strategies analyzed upon removal of the economic effects from bird predation, with greater effects occurring on smaller‐scale farms. One‐third of the farm size and production scenarios analyzed changed from being unprofitable to showing a profit in the absence of such negative economic effects associated with bird depredation. Overall, the combined effects of increased farm expenditures to scare birds from farms and the value of the catfish lost to predation by cormorants caused substantial negative economic effects on catfish farms.     

The Economic Impact of the Catfish,Ictalurus punctatus,Industry on Chicot County,Arkansas

Abstract

This study analyzed the contribution of the catfish industry to the economy of Chicot County, Arkansas, using an input-output model. The objective was to quantify the economic contribution of the industry in terms of creating new dollars, jobs, and income to the local community. Mail surveys and personal interviews were used to collect data from catfish farmers, processors and other businesses related to the catfish industry. For farmers, the information solicited included production and marketing costs, sales and employment. Out of approximately 85 questionnaires administered to catfish farms, 44 usable questionnaires were obtained for a response rate of 52%. Businesses directly related to the catfish industry provided information on employment and sales and included: processors, seiners and haulers, pond builders, tractor and equipment dealers, and feed bin manufacturers. Other businesses with indirect ties to the catfish industry included: input supply companies, banks, fertilizer and chemical companies, auto shops, electricians, and bookkeeping firms. The survey data were used to modify the IMPLAN database for Chicot County to reflect the 2001 level of catfish production, processing and services available to support the industry. This database was then used to estimate the economic impact of the industry to the county's economy. In 2001, the 85 catfish farmers in the county operated about 7,859 ha (19,500 acres). The farm-gate value of catfish production exceeded $63 million. Employment on catfish farms was approximately 510. In addition, 59 other businesses depended on the catfish industry. Results indicated that total employment created in Chicot County by businesses directly or indirectly involved with the catfish industry was 2,665 jobs. This represented 48% of all employment in Chicot County. Total tax revenue (federal, state, and local taxes) generated from both direct and indirect catfish businesses was $22 million. Combined, the total economic impact of the catfish industry in Chicot County, including direct, indirect and induced effects, was over $384 million. The output multiplier calculated for live catfish production was 6.05. Thus, each $1 of earnings by catfish farms generated $6.05 total economic activity in the Chicot County economy. If current economic difficulties should result in contractions in catfish acreage in Chicot County by 10%, unemployment rates would increase by 2%. This study demonstrates the importance of the catfish industry to the economy of Chicot County.     

Factors influencing the variance in expected yield on catfish farms in the United States

Analysis of data from a cross-sectional survey of 571 catfish farmers in the four major catfish-producing states in the United States showed that variability in production fell as farm size increased. Increasing pond size was associated with increasing variability in production. The variance of production was higher on operations that had watershed ponds than on operations with levee ponds.     

Evaluation of a Barrier Confinement System for Channel Catfish,Ictalurus punctatus,Production

An in‐pond confinement system to separate channel catfish, Ictalurus punctatus, by size within a single pond provides an opportunity for improved growth of understocked fish in ponds with larger market‐sized fish. A barrier of polyvinyl chloride–coated galvanized wire mesh was constructed in five 0.10‐ha earthen ponds to partition the pond into one‐third and two‐third sections, while five other 0.10‐ha ponds were left as traditional open ponds for a control. To evaluate catfish performance in this confinement system, fingerlings (25 g) were stocked at 14,820/ha into the smaller one‐third section of the barrier and carryover fish (408 g) at 2580 kg/ha into the larger two‐third section of the barrier. The control ponds were stocked with the same sizes and numbers of fish in a traditional earthen pond without a barrier. Yield, survival, feed conversion ratio (FCR), growth, and economics were compared between treatments. Fingerling yields were greater in the barrier system that allowed fingerlings to be separated physically from larger carryover fish. There were no differences in yield of carryover fish, survival, FCR, or growth between the control and the barrier ponds. Partial budget analysis revealed a positive net change of $367/ha or $38,125 for a 104‐ha catfish farm (at a market price of $1.54/kg of additional stockers produced). The value of the greater weight of understocked fish produced in the barrier system was greater than the annualized cost of installing the barrier, for farmers raising fish in multiple batch. Thus, on an experimental basis, the confinement system was economically profitable; however, trials on commercial farms are needed to evaluate performance on a larger scale.     

Costs and Risk of Catfish Split‐pond Systems

Split ponds are recently developed pond‐based aquaculture systems that allow intensification of catfish aquaculture. Successful industry‐wide adoption of newly developing technologies like split‐pond systems will depend upon their productivity and cost efficiencies. Costs and production performance of the following three split‐pond design scenarios were monitored in Arkansas and Mississippi: (1) research design developed at the Thad Cochran National Warmwater Aquaculture Center, Stoneville, Mississippi; (2) waterwheel design tested on commercial catfish ponds; and (3) screw‐pump design tested on commercial catfish ponds. An economic engineering approach using standard enterprise budget analysis was used to develop estimates of breakeven prices (BEPs) ($/kg) for producing foodsize hybrid catfish (♂Ictalurus furcatus × ♀Ictalurus punctatus) for each scenario. Estimates of BEPs of hybrid catfish raised in split ponds ranged from $1.72 to $2.05/kg. The cost of catfish production in split ponds was sensitive to yield, fish prices, and feed prices. Annual net cash flows from both commercial split‐pond systems were high and sufficient to make the investment profitable in the long run. Feed price, feed conversion ratio, and yield contributed the most to downside risk of split ponds.     

Comparison of intensive shrimp farming systems in Indonesia, Philippines, Taiwan and Thailand

The estimated production of cultured shrimps for 1995 in Taiwan, the Philippines, Indonesia and Thailand was 20 000, 40 000, 80 000 and 220 000 tonnes, respectively. Intensive shrimp ponds in the Philippines (71%) and Indonesia (63%), which are developed in the tidal and mangrove areas, cannot be properly treated by complete drying, owing to seepage from supply and drainage, nor by removal of the fouled layer by heavy machines such as bulldozers. Intensive farms in Thailand and Taiwan are owned by small-scale operators operating 2-3 ponds simultaneously, each ranging from 0.16 to 1.0 ha, which is the optimal size for efficient farm management and lower overhead and investment costs compared with larger farms such as those found in Indonesia and the Philippines. In Taiwan, 90% of pond water supply is mixed open sea water with underground fresh water. Pond salinity, which is kept constant at 10-15%o, causes Taiwanese farmers to encounter an array of problems which include high cost of underground water pumping, land subsidence, salinization, more pathogens and rapidly fouled bottom. Water loss by seepage in Thailand is minimal (average 23 cm in the final month), compared with Indonesia and the Philippines, because pond dikes are tightly compacted by heavy machines and high clay content (86%). Circular water movement in ponds in Thailand, facilitated by heavy aeration (13.3 hp ha^?1), aids in the settling of waste in pond centres for easy removal. Indonesia and the Philippines still maintain high water exchange systems (335 cm and 470 cm in the final month, respectively) which introduce viruses, other pathogens, excess organic loads, ammonia and other toxic particles released by nearby farms through the incoming water. Despite serious crop failures in other countries within the past few years, the annual shrimp production in Thailand still remains high because farmers have readily adopted new, environmentally friendly and locally suitable, water exchange systems such as less water exchange, and closed, full-strength seawater and freshwater systems, overcoming heavy viral and disease infections. Approximately 30% of shrimp production in Thailand comes from the freshwater areas, sometimes 200 km from the sea. Half of the Philippine farmers rely on imported feeds; this has caused high shrimp mortality owing to toxins produced from expired feeds kept in humid conditions.     

The Potential Use of Mangrove Forests as Nitrogen Sinks of Shrimp Aquaculture Pond Effluents: The Role of Denitrification

A generalized nitrogen budget was constructed to evaluate the potential role of mangrove sediments as a sink for dissolved inorganic nitrogen (DIN) in shrimp pond effluents. DIN concentrations were measured in pond effluents from three semi-intensive shrimp ponds along the Caribbean coast of Colombia between 1994–1995. Mean NH₄⁺ concentrations in the discharge water for all farms were significantly higher (67 × 12 μg/L) than in the adjacent estuaries (33 × 8 μg/L). Average NH₄⁺ concentrations in the pond discharge over all growout cycles were similar, representing an approximate doubling in relation to estuarine water concentrations. In contrast, NO₂^-+ NO₃^- concentrations were similar in both pond effluent and estuarine waters. Dissolved inorganic nitrogen loading of the ponds was similar. The estimated reduction of DIN in pond effluents by preliminary diversion of outflow to mangrove wetlands rather than directly to estuarine waters would be × 190 mg N/m² per d. Based on this nitrogen loss and depending upon the enrichment rate, between 0.04 to 0.12 ha of mangrove forest is required to completely remove the DIN load from effluents produced by a 1-ha pond.     

Marine shrimp aquaculture: a novel waste treatment system

Ecuadorian Penaeus vannamei were cultured in dirt ponds (each of approximately 163 m²) at four different stocking densities, i.e. 5 shrimp m⁻², 10 shrimp m⁻², 15 shrimp m⁻² and 20 shrimp m⁻². Experiments were carried out over three different periods during the year. Each experiment lasted for 11–14 weeks. No commercial feed was given to the shrimp. The only input to the ponds was about 30 kg of cattle manure per pond per week. Chemical composition of the cattle manure was analyzed. Water quality parameters such as temperature, pH, DO and turbidity were recorded twice daily for each experiment; nutrients (nitrite, nitrate, ammonium and phosphate), water ATP, sediment ATP, H₂S and chlorophyll were measured twice weekly for each experiment. Shrimp were sampled either weekly or bi-weekly for body weight measurements.

The results showed a negative correlation between stocking density and growth. Weekly growth ranged from 0·44 to 1·58 g week⁻¹. Survival was over 50% in all treatments and averaged at 70·8%. Under these stocking densities, shrimp production ranged from 4·4 to 18·8 kg ha⁻¹ day⁻¹. The stocking density of 15 shrimps m⁻² provides better production than the other stocking densities.

Water quality data did not relate to any shrimp growth. Water nutrient levels in pond discharge water were less than or equal to the nutrients in the incoming water in spite of the weekly addition of cattle manure and did not increase with the addition of cattle manure. No coliform bacteria were detected in any pond water samples through the study period. This indicates digestion of cattle manure in marine shrimp ponds would not pollute the environment with high concentrations of dissolved nutrients.

Thus, a marine shrimp pond can be considered a dissolved nutrient marine treatment plant converting unwanted cattle manure (1841 kg cattle manure ha⁻¹ week⁻¹ in this study) into a valuable commodity — shrimp.     

Regulatory costs on U.S. salmonid farms

The economic effects of the implementation of regulations on aquaculture farms in the United States, while of concern, are not well understood. A national survey was conducted of salmonid (trout and salmon) farms in 17 states of the United States to measure on‐farm regulatory costs and to identify which regulations were the most costly to this industry segment. The response rate was 63%, with a coverage rate of 94.5% of the U.S. production of salmonids. The regulatory system resulted in increased national on‐farm costs of $16.1 million/year, lost markets with a sales value of $7.1 million/year, lost production of $5.3 million/year, and thwarted expansion attempts estimated at $40.1 million/year. Mean farm regulatory costs were $150,506/farm annually, or $2.71/kg; lost markets with annual sales values of $66,274/farm; annual lost production of $49,064/farm; and an annual value of thwarted expansion attempts estimated at $375,459/farm. Smaller‐scale farms were affected to a disproportionately greater negative extent than larger‐scale farms. Per‐farm regulatory costs were, on average, greater for foodfish producers than for producers selling to recreational markets, but per‐kg regulatory costs were greater for those selling to recreational compared to foodfish markets. Regulatory costs constituted 12% of total production and marketing costs on U.S. salmonid farms. The greatest regulatory costs were found to be effluent discharge regulations. The majority of regulatory costs were fixed costs, but regulatory barriers to expansion precluded compensatory adjustments to the business in spite of growing demand for salmonid products. Results of this study show that the on‐farm regulatory cost burden is substantial and has negatively affected the U.S. salmonid industry's ability to respond to strong demand for U.S. farm‐raised salmonid products. Results also suggest that the regulatory system has contributed to the decline in the number of U.S. salmonid farms. While regulations will necessarily have some degree of cost to farms, the magnitude of the on‐farm regulatory cost burden on U.S. salmonid farms calls for concerted efforts to identify and implement innovative regulatory monitoring and compliance frameworks that reduce the on‐farm regulatory cost burden.     

Biochemical Oxygen Demand in Channel Catfish Ictalurus punctatus Pond Waters

A study of the biochemical oxygen demand (BOD) of waters from ten channel catfish ponds at Auburn, Alabama, revealed that the 5-d BOD (BOD₅) seldom exceeded 8 mg/L and that the ultimate BOD (BOD_u) was usually less than 30 mg/L. Water samples from catfish ponds usually needed to be diluted only 2 or 3 times to permit BOD₅ measurements, and nitrification occurred even during a 5-d incubation period. Catfish pond waters were not extremely high in ammonia nitrogen concentration, and ammonia nitrogen introduced in the ammonium chloride-enriched dilution water caused an appreciable increase in BOD of some samples. Plankton respiration is a major component of carbonaceous BOD (CBOD) in catfish pond waters. Thus, the BOD is not expressed as rapidly during 5-d incubations as in typical waste-water. The ultimate BOD (BOD_u) would be a good measurement of oxygen demand for catfish pond effluents, but it is difficult to measure. Data from this study suggest that BOD_u can be estimated from BOD₅, but the correlation is not strong ( R ²= 0.62). An alternative is to develop a short-term BOD measurement specifically for effluents from channel catfish and other aquaculture ponds. This study suggests that a 10-d BOD conducted without nitrification inhibition or addition of ammonia nitrogen in dilution water might be a better alternative to standard BOD₅ or BOD_u measurements normally used in wastewater evaluation.     

Suspended Solids from Baitfish Pond Effluents in Drainage Ditches

Effluents from aquaculture facilities vary between species and among production systems. Drainage ditches commonly convey effluents from central Arkansas baitfish ponds. Ditches could potentially reduce suspended solids prior to effluent release into receiving streams through settling. We characterized suspended solids in effluents from baitfish ponds and evaluated changes in suspended solids in drainage ditches. We also characterized drainage ditches based on width, depth, slope, and percent vegetation cover. Average (± SD) total suspended solids (TSS) at the point of discharge was 52 (± 41) mg/L, while volatile suspended solids (VSS) averaged 22 (± 23) mg/L. Screening effluents did little to alter their composition. Approximately 76% of TSS were less than 5 μm. There were no significant changes in effluent solids along drainage ditches 100 m from the point of discharge and no significant correlations between ditch characteristics and changes in either TSS or VSS. Existing ditches are quite variable and are not necessarily effective in removing solids present in baitfish effluents. Screening and use of ditches as settling basins seem impractical for effluent treatment given the characteristics of solids in baitfish effluents.     

Improving water‐use efficiency for Ictalurid catfish pond aquaculture in Northwest Mississippi,USA

We used a 50‐year (1961–2010) daily record of precipitation and evaporation in a hydrological model to simulate ground water withdrawal for the foodfish grow‐out phase of ictalurid catfish culture in northwest Mississippi, USA. The model quantified the effects of seepage, reusing water for multiple years, and managing water levels to capture rainfall (drop‐fill water management). Selecting sites with relatively impervious soils and reusing water for multiple years had large impacts on annual water use, and combining those practices with drop‐fill water management reduced simulated groundwater withdrawal to less than 60 cm year^?1 compared with more than 450 cm year^?1 for the least conservative scenario. Water conservation measures reduced estimated costs of pumping ground water from ~$1150 ha^?1 year^?1 for the least conservative set of water‐use variables to less than $110 ha^?1 year^?1 for the best set of water conservation practices. Efficiency of pumped water use was dramatically improved by intensifying production in the foodfish grow‐out phase. Combining water‐conservation practices with production intensification improved the water use index from 9.18 m³ kg^?1 for foodfish grow‐out ponds with the least conservative set of practices to 0.28 m³ kg^?1 for ponds built on soils with negligible seepage, managed with a 22.9‐cm drop/7.6‐cm fill, drained every 10 years, and producing 15 000 kg of catfish ha^?1 year^?1. When simulated ground water use for the best set of water conservation practices in foodfish grow‐out ponds was combined with estimates of ground water used for fingerling production and water used in producing grain‐based feedstuffs, total consumptive water use index for catfish culture was estimated at ~2.7 m³ kg^?1. This index is competitive with most other types of animal agriculture. Efficient water use in catfish farming is easily achieved under commercial conditions using existing simple technologies.     

Mathematical Model of Channel Catfish Foodfish Production in Multiple-Batch

Market size requirements for catfish change periodically, and catfish farmers must adjust quickly. Data from catfish pond studies at the University of Arkansas at Pine Bluff (UAPB) were used to develop mathematical models of catfish foodfish in multiple-batch culture across a variety of management alternatives. Two different functional forms (Cobb–Douglas and a modified translog) were each developed into average and stochastic frontier models. Inefficiency terms were found to be non-significant in the frontier models, thus making the average and frontier models equivalent. In the average regression models, the modified translog form demonstrated superior statistical values as compared to the Cobb–Douglas form, but the latter resulted in lower prediction error and was validated with the Chow test when used to predict observations from commercial catfish farms. This approach appears to have merit from the perspective of its statistical properties, and represents a step towards development of a model that could be used for farm management purposes.     

Economics of Intensively Aerated Catfish Ponds

The US catfish industry is evolving by adopting production‐intensifying practices that enhance productivity. Catfish producers have increased aeration rates over time, and some now use intensive rates of aeration (>9.33 kW/ha). Costs and production performance were monitored at commercial catfish farms using high levels of aeration (11.2–18.7 kW/ha) in Alabama, Arkansas, and Mississippi. A multivariate‐cluster analysis was used to identify four different management clusters of intensively aerated commercial catfish farms based on stocking density, size of fingerlings at stocking, and feed conversion ratios (FCR). Breakeven prices of hybrid catfish raised in intensively aerated pond systems were estimated to range from $1.86/kg to $2.17/kg, with the lowest costs associated with the second greatest level of production intensity. The two medium‐intensity clusters generated sufficiently high revenues for long‐term profitability. However, the least‐intensive and the most‐intensive clusters were economically feasible only when catfish and feed prices were closer to less probable market prices. Feed price, FCR, and yield contributed the most to downside risk. Intensive aeration in catfish ponds, up to the levels analyzed in this study, appears to be economically feasible under the medium‐intensity management strategies identified in this analysis.     

Comparative Economics of US Catfish Production Strategies: Evidence from a Cross‐sectional Survey

Understanding the effects of specific management strategies on yields and economic outcomes on commercial catfish farms could provide useful guidance to catfish farmers on the most profitable sets of production practices. Data from the U.S. Department of Agriculture–National Animal Health Monitoring System (USDA–NAHMS) 2009 survey of production practices on catfish farms in Alabama, Arkansas, Louisiana, and Mississippi were used to identify five clusters of catfish farms that use various stocking densities, channel versus hybrid catfish, different aeration levels, and utilize automated oxygen sensors. The lowest production costs ($1.96/kg) were found in cluster 1 and were followed in order of increasing costs per kilogram of clusters 2 and 4 ($2.16/kg) and cluster 5 ($2.73/kg); the highest cost corresponded to cluster 3 ($2.84/kg). The lowest risk levels corresponded to the clusters with the lowest production costs per kilogram of fish and the highest risk levels to the highest production costs. This analysis demonstrated that different types of management models can achieve similar levels of production costs ($/kg), and it appears that there is not one single economically optimum way to raise catfish. The key to least‐cost production is to balance the use of inputs, their associated costs, and the yield produced to achieve economic efficiency within the farm's overall business and management model.     

Cost of regulations on US catfish farms

Understanding the economic effects of regulations on US aquaculture farms provides insights into which compliance costs create the greatest compliance burden on farms. This can further guide strategies to improve the efficiency of regulatory frameworks and potentially reduce on-farm compliance costs while maintaining adequate oversight. This study estimated the regulatory compliance burden on US catfish farms as part of a national effort to quantify the cost of regulations on US aquaculture farms. Completed survey interviews of catfish farms in the major catfish-producing states covered 63% of the total US catfish production area. Total regulatory costs of the US catfish industry were estimated at $45 million annually. Lost farm revenues (measured as the value of lost production, the value of markets lost from regulations, and the value of business opportunities lost because of regulations) were estimated to be $35 million per annum. Catfish-producing states outside the Alabama/Arkansas/Mississippi region had the highest ($2856/ha) and Alabama the lowest ($1127/ha) regulatory costs per hectare among the surveyed states. The greatest regulatory cost burden on catfish farms ($18 million) was caused by environmental regulations related mostly to the management of federally protected piscivorous migratory birds, followed by labor regulations ($12 million), and taxes/insurance ($7 million). Regulatory costs ($/kg) were 2.6 times higher on smaller (<80 ha) farms relative to larger (>300 ha) farms. Attention is needed to identify alternative regulatory frameworks that provide the same degree of regulatory oversight but are more cost-efficient.