Carbon Footprint Assessment of Recirculating Tank and Pond Systems for African Catfish (Clarias gariepinus) in Sta. Cruz, Laguna, Philippines

The carbon footprint of aquaculture in the Philippines remains underexplored, and the data on species-specific emissions across various aquaculture systems are limited. This study evaluates the carbon footprint of African catfish production in recirculating tank and pond systems through a cradle-to-gate approach. Greenhouse gas emissions were quantified for each phase of fish culture, including facility establishment, production, harvesting, packaging, and distribution. This study showed that catfish farming in a recirculating system with a stocking density of 45 kg m^-3 and a cropping frequency of 2 cycles per year generated 12.04 kg CO₂ eq kg LW^-1 or 5.01 ton CO₂ eq yr^-1. In contrast, the pond system with a stocking density of 10 kg m^-3 and the same cropping frequency produced an average of 2.80 kg CO₂ eq kg LW^-1, or 17.7 tons CO₂ eq yr^-1. The production phase was the largest contributor to the overall carbon footprint in both systems, with electricity comprising 75% of emissions in the recirculating tank system and fish feed accounting for 93% in the pond system. Moreover, the scenario used to evaluate the impacts of energy consumption and fingerling delivery logistics on the farm’s overall carbon footprint indicated a reduction in emissions by about 76% by switching to solar energy and utilizing locally produced fingerlings. These findings provide a viable approach to mitigating the environmental impact of African catfish farming in the Philippines.