Northern Shrimp (Pandalus borealis) on Flemish Cap Surveys 2007
A stratified random bottom trawl survey on Flemish Cap was carried out from June 21th to July 21th 2007. The area surveyed was extended up to depths of 800 fathoms (1400 meters) following the same procedures as in previous years and increasing the number of hauls planned (195). A total of 174 valid hauls were made by the vessel R/V Vizconde de Eza with the usual survey gear (Lofoten), 117 up to 730 meters depth. The general indexes for shrimp were estimated taken into account the traditional swept area (strata 1-19, up to depths of 730 m.) and the total area surveyed (strata 1-34, up to depths... Mehr ...
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Dokumenttyp: | workingPaper |
Erscheinungsdatum: | 2007 |
Verlag/Hrsg.: |
Centro Oceanográfico de Vigo
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Sprache: | Englisch |
Permalink: | https://search.fid-benelux.de/Record/base-26700242 |
Datenquelle: | BASE; Originalkatalog |
Powered By: | BASE |
Link(s) : | http://hdl.handle.net/10508/667 |
A stratified random bottom trawl survey on Flemish Cap was carried out from June 21th to July 21th 2007. The area surveyed was extended up to depths of 800 fathoms (1400 meters) following the same procedures as in previous years and increasing the number of hauls planned (195). A total of 174 valid hauls were made by the vessel R/V Vizconde de Eza with the usual survey gear (Lofoten), 117 up to 730 meters depth. The general indexes for shrimp were estimated taken into account the traditional swept area (strata 1-19, up to depths of 730 m.) and the total area surveyed (strata 1-34, up to depths of 1400 m.). The results concerning shrimp are presented and compared to those from previous years of the same series. The biomass and abundance in 2007 were similar to 2006 and at levels prior to 1998 . Although the abundance decreased about 11% respect to 2006, the biomass in 2007 with 17045 t. was about 5% greater than 2006. This fact was mainly due to the important presence of the oldest ages belonging to the 2000-2002 strong year classes (5-7 ages group). In the other side, as in the last years (2004-2006) the youngest specimens (age 1) didn’t appear in the catches, and they were weakly presents in the small mesh size bag attached to the cod-end, suggesting the absence of any strong year classes since 2003.