Northern Shrimp (Pandalus borealis) on Flemish Cap Surveys 2017
A stratified random bottom trawl survey on Flemish Cap was carried out from June 14thto July18th2017. The area surveyed was extended up to depths of 800 fathoms (1450meters) following the same procedures as in previous years. This year a total of 181valid hauls were made by the vessel R/V Vizconde de Ezawith the usual survey gear (Lofoten), 120up to 730 meters depth.The surveyed area has properly prospected the 32 strata planned. 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... Mehr ...
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Dokumenttyp: | Artikel |
Erscheinungsdatum: | 2017 |
Verlag/Hrsg.: |
Centro Oceanográfico de Vigo
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Schlagwörter: | statistical sampling / botton trawl research surveys / Pandalus borealis |
Sprache: | Englisch |
Permalink: | https://search.fid-benelux.de/Record/base-29060934 |
Datenquelle: | BASE; Originalkatalog |
Powered By: | BASE |
Link(s) : | http://hdl.handle.net/10508/11666 |
A stratified random bottom trawl survey on Flemish Cap was carried out from June 14thto July18th2017. The area surveyed was extended up to depths of 800 fathoms (1450meters) following the same procedures as in previous years. This year a total of 181valid hauls were made by the vessel R/V Vizconde de Ezawith the usual survey gear (Lofoten), 120up to 730 meters depth.The surveyed area has properly prospected the 32 strata planned. 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 1450m.). As the last yearsthe strata 26 and 27sited in the southeast of the bank with depths from 600 to 800 fathoms (1100-1400 m.) will not be surveyed due to the presence in the bottoms of great quantities of mud and sponges. The results concerning shrimp are presented and compared to those from previous years of the same series. In recent years 2015, 2016 and 2017 the total biomass indexes increased significantly compared to previous year (around 72%, 62% and 14% respectively) but remain at very lowlevel. The total and female biomasses estimated in 2017 were 2885 t and 2304 t respectively (Table 1).As in previous years the youngest specimens (age 1, around 10 mm CL) barely appearedin the catches and the abundance at age 2 (around 16 mm CL) was weakly presents suggesting the absence of any strong year classes since 2004.This poorsituation of theshrimpstockis associated, as in previousyearswiththegoodcondition of thecodstock. ; Versión del editor ; 0