Speaking at an aquaculture forum during the EuroTier exhibition in Germany, IMARES researcher Marnix Poelman explained that the comparison had looked at a Dutch recirculation process for African catfish and a pond system for Pangasius in Viet Nam.
These were real-life cases, he emphasised, with each stage examined from the production and processing of the feed raw materials used in each system to the delivery of the end product.
The study found that the carbon footprint of both systems was similar to those previously reported for other aquaculture methods and also for chicken, so lower than for pork or beef. Producing fish in ponds had a bigger footprint than from a recirculation (RAS) approach, due mainly to a poorer feed conversion ratio of the pond-cultured fish and its effect of magnifying the substantial contribution from feed composition and the volume and type of waste.
Surprisingly, said Mr Poelman, the energy used in production made relatively little difference to the total carbon dioxide emitted per kilogram of fish produced.
In round terms, the pond system was associated with 5.0 kg CO2 per kg fish whereas the figure for the recirculation system was 3.8 kg. These values must be put into perspective, Mr Marnix declared. For example, an air flight within Europe could have a carbon footprint of several hundred kilos.
EUROTIER: Carbon Footprints From Farmed Fish
GERMANY - One of the first controlled studies to compare the carbon footprint of recirculation and pond systems for farmed fish has been undertaken by the IMARES unit of Wageningen University and Research Centre in the Netherlands.
