I estimated yield, population metrics, production costs, and evaluated consumer acceptability and nutritive content of crayfish (Procambarus clarkii, P. zonangulus) harvested from moist-soil wetlands in the Lower Mississippi Alluvial Valley (MAV) during springs 2009-2011. I also compared nutrient and sediment concentrations and loads exported from moist-soil wetlands and nearest agriculture fields in the MAV during winters 2010-2012. Daily yield of crayfish from moist-soil wetlands was 2.4 kg (wet) ha-1 (SE = 0.50; 95% CI = 1.3-3.4). When graded by size, yield of large crayfish (> 30 g) from wetlands dominated by P. clarkii was four times greater (P < 0.05) than yield of large crayfish from wetlands dominated by P. zonangulus. Crayfish harvesting costs (2013 US dollars [$]) ranged from $405.69 ha-1 to $917.88 ha-1 and breakeven selling prices ranged from $3.74 kg-1 to $8.49 kg-1. Consumer acceptability, proximate composition, and total fatty acid content of P. clarkii did not differ (0.73 > P > 0.11) between crayfish harvested from moist-soil wetlands and rice-crayfish culture fields in Louisiana. Although selling prices likely will not compete with prices for crayfish harvested from Louisiana rice fields ($2.75 kg-1; 2012 US$), harvesting crayfish from moist-soil wetlands may enhance recreational opportunities while increasing awareness of ecosystem benefits of these wetlands. Although concentrations (mg L-1) of soluble reactive phosphorus (SRP) in runoff from moist-soil wetlands and adjoining croplands did not differ (P = 0.95), concentrations of total and particulate phosphorus, nitrate-nitrogen, and total suspended solids were 42, 52, 86, and 89% lower (P < 0.03) in runoff from moist-soil wetlands. However, the load (kg ha-1) of SRP from moist-soil wetlands was six times (P = 0.08) greater than load from croplands. Estimated loading rate of total phosphorus from moistsoil wetlands (2.36 kg ha-1 year-1) was greater than the rate reported by regulatory agencies in Mississippi (1 kg ha-1 year-1), but field replication is needed to verify these results. Nearly 80% of the total loads exported from moist-soil wetlands occurred during < 30% runoff events. Retention of runoff from storm events may reduce phosphorus loss from moist-soil wetlands while not interfering with conservation objectives.

This research provides a comprehensive picture of the economic status of the U.S. catfish industry through investigating several critical economic aspects such as technological progress, functional production relationships in intensive systems, regulatory costs, and economic contribution of the industry. The use of primary data is a unique aspect of this work reflecting the economic realities of catfish farms. Primary data collected through extensive in-person farm surveys covered over two-thirds of the catfish production areas in the U.S. The results of the study provided evidence of intensification in the U.S. catfish industry through increased adoption of two relatively new alternative production systems viz; intensively aerated ponds (6,315 ha) and split ponds (1,176 ha). The use of complementary technologies such as hybrid catfish on 53% of the catfish producing area and increased fixed-paddlewheel aeration rate of over 7.8 kW/ha also provided proof of technological progress on U.S. catfish farms. This study also identified critical factors contributing to productivity in increasingly adopted alternative production systems through two distinct production function models. Feed fed, as well as stocking biomass were found to be significant variables in both production functions. Results indicated further room for improvement in the use of inputs to increase production, especially in feed management. Along with identifying the nuances in the catfish industry, the study quantified regulatory costs on U.S. catfish farms at $45 million. Although faced with several hardships on the production front, the U.S. catfish industry contributes over $1.9 billion to the regional economy, supports more than 9,100 jobs, and generates over $78 million in tax revenues. The findings of the study serve a multitude of stakeholders including aquaculture farmers, researchers, Extension specialists, and policymakers who work towards improving the economic sustainability of the catfish industry as well as the U.S. aquaculture industry.