Trawl-caught cod survive with vacuum pumping
Experiments in collaboration with Nergård Havfiske AS show that pumping from the trawl’s cod-end is gentler for the fish than lifting the complete catch onto the deck. Survival is higher, quality higher, and we now know more about the design of future trawlers.
Experiments onboard the trawler “J. Bergvoll” in May have shown that pumping is considerably more gentle than pulling up onto the ramp and survival rates of 80-100%, depending on species, can be achieved.
Fish caught by trawling should be kept alive in tanks for 5-6 hours, long enough for blood to be removed from the white muscles.
“This is the first time vacuum pumping has been used to get the fish onboard from the cod-end on a trawler. Pumping ensures that the fish are in contact with water all the time, and they are not subject to gravity. Using this method means that the quality, and thus also the price, of trawl-caught fish are at least as good as those of line-caught fish,” says Kjell Midling from Nofima and head of the Norwegian Centre of Excellence for Capture-based Aquaculture
Refurbishing old boats or building new ones
The opportunities offered by new technology in the trawler industry are being studied in a project financed by the Norwegian Seafood Research Fund (FHF). Several shipowners are considering installing pumping facilities when refurbishing old boats or building new ones.
Nofima is taking the collaboration further with Nergård Havfiske AS, ship designers, equipment manufacturers, and pump suppliers to ensure that trawl-caught fish has as high a quality as possible.
“Knowledge about live fish is crucial for the future of the trawler industry. The new technology is based on 25 years of experience about what the fish can withstand, and the conditions necessary for survival. This will determine how the new technology is implemented,” says Midling.
The research is part of the extensive CRISP project, which is a project centred on research-based innovation in sustainable fish capture, quality and economics.
The goal of CRISP is to contribute to increased creation of value in the Norwegian seafood industry, and to reduce its impact on the environment.
Several of the projects on which the new technology is based have been financed also by the Norwegian Seafood Research Fund (FHF).