Economic Analysis and Improvement Opportunities of African Catfish ( Clarias gariepinus ) Aquaculture in Northern Germany

A farmland based African Catfish recirculation aquaculture system with a production volume (PV) of 300 m 3 was modelled under realistic market conditions in order to analyse the impact of price fluctuations on profitability. As a monoculture recirculating aquaculture system (RAS) for whole fish and the wholesaler’s market, the model northern German catfish aquaculture is currently gainless, but the production is sufficient to cover all costs. The most decisive economic parameter is the low selling price (2.20 EUR/kg whole fish), which affects the returns by ±70,463 EUR/year for every ten percent (0.22 EUR) price change. Among the variable costs, feed has by far the largest impact with a share of 61.4% (42.1% of total costs). Based on the initial model every ten percent price variation of this variable input factor changes the returns by ±29,691 EUR/year, followed by energy (±5913 EUR/year), fingerlings (±4804 EUR/year), wages (±3972 EUR/year) and water (±2464 EUR/year). Larger system sizes (600 m3 PV) significantly save costs due to economies of scale and achieve returns of 175,240 EUR/year and an ROI of 11.45%. Increasing max. stocking density from 450 kg/m 3 to 550 kg/m 3 improves returns and ROI (40,379 EUR/year; 4.40%), but also involves higher production risks. An own fingerling production with a production of 300% above the own requirements improves returns and ROI (39,871 EUR/year; 3.57%) and leads, above all, to independence from foreign suppliers. Aquaponic integrations can generate profits, but are associated with high investment costs and the challenges of entering a new business sector. Product diversification into fillet (50% of the production) and smoked fillet (30%) generates lucrative returns and ROI (212,198 EUR/year; 20.10%). Profitability is further increased by direct marketing in the form of a farm store and the establishment of a regional “producer organisation”. Our results demonstrate that under current market conditions northern German catfish aquaculture covers all costs, mainly increasing profitability through altered sales prices and feed costs. Retaining a larger part of the fishery value chain within the farm through additional benefits, further processing and product diversification improves profitability, making African catfish RAS a sustainable and economically profitable aquaculture business in Germany.