Marine Institute Open Access Repository >
Marine Institute Community of Research Publications >
Survey Reports >
Nephrops Under Water TV Surveys >

Please use this identifier to cite or link to this item:

Title: Western Irish Sea Nephrops Grounds (FU15) 2017 UWTV Survey Report and catch options for 2018
Authors: Clements, A.
Doyle, J.
Lordan, C.
Lundy, M.
McCorriston, P.
McArdle, J.
McCausland, I.
Burns, G.
Schön, P.J.
Keywords: Nephrops norvegicus
stock assessment
underwater television (UWTV)
Issue Date: 2017
Publisher: Marine Institute
Citation: Clements, A., Doyle, J., Lordan, C., Lundy, M., McCorriston, P., McArdle, J., McCausland, I., Burns, G. and Schön P.-J. 2017. Western Irish Sea Nephrops Grounds (FU15) 2017 UWTV Survey Report and catch options for 2018. AFBI and Marine Institute UWTV Survey report.
Series/Report no.: Marine Institute UWTV Survey report;2017
Abstract: This report provides the main results and findings of the 15th annual underwater television survey on the ‘Irish sea west Nephrops grounds’ ICES assessment area, Functional Unit 15. The survey was multi-disciplinary in nature collecting UWTV and other ecosystem data. The 2017 design consisted of a randomised isometric grid of 100 stations at 4.5 nautical mile intervals out over the full known extent the stock. The resulting krigged burrow abundance estimate was 5.3 billion burrows. This was a similar result of that obtained in 2006, and 4% higher than the abundance in 2016. In contrast to 2016 the spatial distribution of burrows appears more homogenous across the survey area. Overall densities are high and abundance remains stable, well above MSY Btrigger. Reducing the number of stations compared to 2011 has not affected the accuracy of the survey estimate to date. The CV (or relative standard error) of 3% is in line with previous estimates and well below the upper limit of 20% recommended by SGNEPS 2012. Total catches and landings options at various different fishing mortalities were calculated and fishing at Fmsy in 2017 implies a total catch option at Fmsy (=Fmax) of 11,807 tonnes which results in landings of no more than 9,630 tonnes. The only sea-pen species observed in 2017 was Virgularia mirabilis and this was found at 16% of stations ranging from occasional to common, with high densities observed in the south-west of the ground. Trawl marks were noted at 36% of the UWTV stations.
Appears in Collections:Nephrops Under Water TV Surveys

Files in This Item:

File Description SizeFormat
Working Document FU15 UWTW 2017.pdf2.19 MBAdobe PDFView/Open
Use License

Items in the Marine Institute Open Access Repository are protected by copyright, with all rights reserved, unless otherwise indicated.


Valid XHTML 1.0! Marine Institute Copyright © 2011  - Feedback