The use of ecosystem indices to investigate the decline of recruitment and spawning stock biomass in North Sea cod (Gadus morhua L.) ...

• Main Author: Bromley, Peter J.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: ASC 2004 - FF - Theme session 2024
• Subjects: The sea and human culture and societies; Ecosystem observation, processes and dynamics; Pressures, impacts, conservation, and management; Gadus morhua
• Online Access: https://dx.doi.org/10.17895/ices.pub.25349314; https://ices-library.figshare.com/articles/conference_contribution/The_use_of_ecosystem_indices_to_investigate_the_decline_of_recruitment_and_spawning_stock_biomass_in_North_Sea_cod_Gadus_morhua_L_/25349314

No abstracts are to be cited without prior reference to the author.Ecosystem indices were used to investigate possible factors associated with the depression of the recruitment (the abundance of young fish) and spawning stock biomass of North Sea cod from 1977-1998, covering the period since the gadoid outburst of the 1970s. They were derived from time-series of biotic (sandeel recruitment, cod spawning stock biomass (SSB)), abiotic (temperature) and anthropogenic (sandeel landings) data. The temperature and sandeel landings data were subjected to principal component analysis to generate fewer, new variables for modelling purposes. The recruitment estimates for cod at various stages during the first year of life (the 0-group phase) were based on time-series of catch-per-unit-effort data from fishing surveys and from single species and multispecies virtual population analyses. ...