Northern Shrimp (Pandalus borealis) on Flemish Cap Surveys 2019
A stratified random bottom trawl survey on Flemish Cap was carried out from June 29thto July29th2019. 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 180valid 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: | 2019 |
Verlag/Hrsg.: |
Centro Oceanográfico de Vigo
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Schlagwörter: | statistical sampling / Pandalus borealis / Research bottom trawl surveys |
Sprache: | Englisch |
Permalink: | https://search.fid-benelux.de/Record/base-29060933 |
Datenquelle: | BASE; Originalkatalog |
Powered By: | BASE |
Link(s) : | http://hdl.handle.net/10508/11665 |
A stratified random bottom trawl survey on Flemish Cap was carried out from June 29thto July29th2019. 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 180valid 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 biomass indexes have increased significantly since 2015and they are now well above Blim. The total and female biomasses estimated in 2019were 9273t and 8486t 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 (around 16 mm CL) was similar to the estimated in2018 at levels next to reported in2009 and 2010. However unlike 2018 the abundance at age 2 in the small mesh size bag attached on the cod-end showed a significantly increasing thatit could confirm the upward trend in the recent recruitments initiated from 2014.Also in 2019 the estimated abundance at age 1 in the juvenile bag was the second highest value in the historicalseries. If this strong year-class(2018)was confirmed in 2020 it would improve the state of impaired recruitmentand contribute to the recovery of stock. The stock after five years of continuous increases of biomass, now it hasvery low probability of being bellow Blim, allowing a small amount of direct fishing on this stock. Considering the uncertainty about ...