Stock abundance indices and length compositions of demersal redfish and other ginfish in NAFO Sub-area 1 and near bottom water temperature derived from the German bottom trawl survey 1982-2012
Survey abundance, biomass estimates and length compositions for golden and deep sea redfish >= 17 cm (Sebastes marinus and S. mentella), juvenile redfish<17 cm, American plaice (Hippoglossoides platessoides), Atlantic and spotted wolfish (Anarhichas lupus and A. minor) and thorny skate (Raja r...
| Main Authors: | , |
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| Format: | Book |
| Language: | English |
| Published: |
2013
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| Subjects: | |
| Online Access: | https://www.openagrar.de/receive/timport_mods_00008327 https://www.openagrar.de/servlets/MCRFileNodeServlet/timport_derivate_00008327/dn052754.pdf |
| Summary: | Survey abundance, biomass estimates and length compositions for golden and deep sea redfish >= 17 cm (Sebastes marinus and S. mentella), juvenile redfish<17 cm, American plaice (Hippoglossoides platessoides), Atlantic and spotted wolfish (Anarhichas lupus and A. minor) and thorny skate (Raja radiata) in Division 1C to 1F are presented. In 2011, time series for the indices were calculated based on exact swept areas. For golden redfish, American plaice and both species of wolffishes, stocks sizes have declined significantly until the early 1990s and remained at a low level since until 2000. Since then, abundances increased only slightly and for 2012, indices are well below the average values from the 1980’s. For thorny skate, abundances increased in the early 1990s and for deep-sea redfish in the late 1990s. All upward trends observed until 2004-2007 are stagnant since then. All stocks considered are presently composed of small and mainly juvenile specimens except for spotted wolffish. Near bottom water temperature continued to be high since 1996. |
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