Search

Barbaro, A., Einarsson, B., Birnir, B., Sigurðsson, S., Valdimarsson, H., Pálsson, Ó. K., Sveinbjörnsson, S., and Sigurðsson, Þ. 2009. Modelling and simulations of the migration of pelagic fish. – ICES Journal of Marine Science, 66: 826–838. We applied an interacting particle model to the Icelandic capelin stock to reproduce the spawning migration route for three different years, successfully predicting the route for 2008. Using available temperature data and approximated currents, and without using artificial forcing terms or a homing instinct, our model was able to reproduce the observed migration routes from all 3 years. By a sensitivity analysis, we identified oceanic temperature and the balance between the influence of interaction among particles and the particles' response to temperature as the control parameters most significant in determining the migration route. One significant contribution of this paper is the inclusion of orders of magnitude more particles than similar models, which affects the global behaviour of the model by propagating information about surrounding temperature through the school more efficiently. To maintain the same dynamics between different simulations, we argue a linear relationship between the time-step, radii of interactions, and the spatial resolution, and we argue that these scale as N−1/2, where N is the number of particles. [ABSTRACT FROM PUBLISHER]

Stefánsson, M. Ö., Reinert, J., Sigurðsson, Þ., Kristinsson, K., Nedreaas, K., and Pampoulie, C. 2009. Depth as a potential driver of genetic structure of Sebastes mentella across the North Atlantic Ocean. – ICES Journal of Marine Science, 66: 680–690. A primary question that remains to be answered about the fishery for Sebastes mentella is whether it exploits several stocks within the North Atlantic Ocean. To address this issue, 1240 redfish were collected from several fishing grounds in late 2006 and early 2007 and genotyped at 12 microsatellite loci. Contemporary allele frequencies were compared with archived data to examine the temporal stability of the genetic structure. The analyses all revealed the presence of three genetically distinguishable clusters, which persisted throughout the study period, suggesting that the genetic structure detected is genuine. Cluster D included fish from the deep Irminger Sea and west Faroe Islands, and Cluster I included fish only from the Icelandic shelf. All other fish grouped in a third cluster (S). Further analyses revealed that the genetic pattern observed was not primarily attributable to isolation by distance, but rather to depth distribution. [ABSTRACT FROM PUBLISHER]