摘要：Atlantic mackerel (Scomber scombrus L.) is extremely vulnerable towards handling and stress,
which makes it difficult to investigate its survival after contact with fishing gear. By using a new
method, where mackerel were transferred from the purse seine to large net pens in the open sea,
the mortality was estimated after the mackerel had been crowded and thereafter slipped. The
method implied a minimum of handling of the fish beyond normal during the purse seine
fisheries. In two introductory experiments in 2006 and three in 2007, mackerel transferred from a
purse seine catch was crowded in the net pen until ‘boiling’ (panic or flash expansion behavior).
This density was maintained for 10 min in 2006 and 15 min in 2007. The mortality among
crowded fish was 80 to 100 %, while the mortality in untreated control groups was significantly
lower. The experiments also showed that, if necessary, it may be possible to release mackerel
from small purse seine catches, even in several steps. It is, however, crucial that this is done with
