Survival tests of internally tagged herring

Biology and fisheries of the Norwegian spring spawning herring and blue whiting in the Northeast Atlantic. Proceedings of the fourth Soviet-Norwegian Symposium. Bergen, 12 - 16 June 1989.Two separate survival tests were run in an indoor basin. Herring was tagged applying internal metal tags as used in the annua1 tagging experiments on the Norwegian spring-spawners. The mortality caused by tagging was severe in the first few weeks after release, declining to a normal leve1 i n about 8 weeks. The survival of tagged herring in the two tests varied substantially, and the coefficient was calculated to be 0.74 and 0.91 respectively. The difference is explained by the difficulties in handling herring in captivity