Northern Shrimp (Pandalus borealis) on Flemish Cap Surveys 2020

A stratified random bottom trawl survey on Flemish Cap was carried out from June 24thto August4th2020. 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 ...

Verfasser: Casas-Sánchez, J.M. (José Miguel)
Dokumenttyp: Artikel
Erscheinungsdatum: 2020
Verlag/Hrsg.: Centro Oceanográfico de Vigo
Schlagwörter: statistical sampling / Pandalus borealis / bottom trawl research surveys
Sprache: Englisch
Permalink: https://search.fid-benelux.de/Record/base-29060936
Datenquelle: BASE; Originalkatalog
Powered By: BASE
Link(s) : http://hdl.handle.net/10508/11668

A stratified random bottom trawl survey on Flemish Cap was carried out from June 24thto August4th2020. 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 1450 m.). 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. The total biomassindexdecreased27%, breaking the upward trend of recent years. Despite the decrease in biomass the stock continue above Blimand it is from 2018 outside the collapse zone defined by the NAFO PA framework.The total and female biomass indexeswere6 734t and 6 048t respectively. As in previous years the youngest specimens (age 1, around 10 mm CL) barely appeared in the catches and the abundance at age 2 from the main gear increased around 19%from 2019.This increase at age 2 was very higher from the small bag attached on the cod-endwhere was recordedthe second highest value in the survey seriesthat it could confirm the upward trend in the recent recruitments initiated from 2014.However unlike 2019 the abundance at age 1 in the small mesh size bag attached on the cod-end was belowaverage in the series. Considering the overall increasing trend of the stock from 2014 above Blim and the uncertainty aboutthe future recruitments in the fishable stock the next years, Scientific Council agreesnot to change the advice from last year and that the catch in 2021 should not ...