Implications of stock recovery for a neighbouring management unit: experience from the Baltic cod

Research output: Contribution to journalJournal articleResearchpeer-review

233 Downloads (Pure)

Abstract

Cod in the Baltic Sea is assessed and managed as two separate stocks, i.e. eastern and western Baltic cod. The eastern Baltic cod has recently started to recover after several decades of severe depletion. In the present study, we suggest that the recovery of the eastern Baltic cod population has also substantially increased cod abundance in a specific area of the adjacent western Baltic management unit. This is investigated through long time-series of spatially resolved stock assessment data supplemented by genetic analyses of origin of the cod currently found in the transition area between the two populations. Due to immigrating cod from the east, there are currently large spatial differences in cod abundance and mean weight in the western Baltic management unit that raise new management concerns. First, the high abundance of cod of eastern origin found in the western Baltic management unit can mask the relatively poor state of the western Baltic cod population. Second, the current fishing mortality estimates for the entire western Baltic management unit, used as basis for fisheries management, are difficult to interpret as these are highly influenced by mixing of biological populations and the spatial distribution of fisheries.
Original languageEnglish
JournalICES Journal of Marine Science
Volume71
Issue number6
Pages (from-to)1458-1466
ISSN1054-3139
DOIs
Publication statusPublished - 2014

Keywords

  • Original Articles

Cite this