Herring trawled in the open sea in the North Sea are stressed to death in the nets, a new study from the Swedish University of Agricultural Sciences (SLU) shows.
As much as 96 percent of the caught herring were already dead when they reached the ship's deck, according to the study.
The fish that had also lost almost all their scales showed signs of stress - with high levels of stress hormone and extensive hemolysis, where the red blood cells had exploded.
The handling involves unnecessary suffering for the herring, and furthermore, the quality of the meat is impaired, the researchers point out.
"There are still many uncertainties about what happens to the fish in the trawl under the water surface. But we can say with certainty that the herring we examined died first after being exposed to severe stress for a long period," says Albin Gräns, zoologist and associate professor at SLU, in a press release.
The study is a collaboration between SLU and several Danish actors in industry, animal welfare, and research.
