|Long-term variations in recruitment of the Iceland scallop, Chlamys islandica from northern Norway|
Vahl, O. (1982). Long-term variations in recruitment of the Iceland scallop, Chlamys islandica from northern Norway. Neth. J. Sea Res. 16: 80-87
In: Netherlands Journal of Sea Research. Netherlands Institute for Sea Research (NIOZ): Groningen; Den Burg. ISSN 0077-7579, more
After a heavy attack by Asterias rubens in winter 1967-1968 on a bed of Chlamys islandica in Balsfjord, north Norway, the population was almost extinct, but by 1971 the population density seemed restored, and from 1971 to 1979 the mean population density varied between 56 and 70 individuals m-2. A larger variation of the biomass was primarily due to changes inthe age structure of the population caused by varying recruitment. Chlamys islandica is not fully recruited into the population until it becomes sexually mature 4 years old. There is an inverse relationship between the number of eggs spawned m-2 and the density of 4 year old scallops arising from these eggs, and also a highly significant negative correlation between the density of juveniles and that of adults. This indicates that recruitment success of a year class is related to the density of adults already established in the population.