Blar i Brage IMR på forfatter "Harbitz, Alf"

Viser treff 1-17 av 17

    • A zigzag survey design for continuous transect sampling with guaranteed equal coverage probability 

      Harbitz, Alf (Journal article; Peer reviewed, 2019)
      Marine resource surveys in large areas have high cost, and to find an optimal survey design with regard to efficiency and scientific outcome is an important issue. A randomized zigzag design for straight line and curved ...

    • Advice on fishing opportunities for Barents Sea capelin in 2024 — ICES subareas 1 and 2 excluding Division 2.a west of 5°W 

      Howell, Daniel; Nielsen, Anders; Stock, Brian; Ono, Kotaro; Clain, Laura; Fossheim, Maria; Wenneck, Thomas de Lange; Harbitz, Alf; Rodriguez, Alfonso Pérez; Iriondo, Ane; Staby, Arved; Bogstad, Bjarte; Husson, Berengere; Marshall, C. Tara; Tranang, Caroline Aas; Johannesen, Edda; Vozgirdas, Eduardas; Eriksen, Elena; Eidset, Elise; Hallfredsson, Elvar H.; Berg, Erik; Skaret, Georg; Höffle, Hannes; Jacobsen, Jan Arge; Stiansen, Jan Erik; Godiksen, Jane Aanestad; Janusz, Jerzy; Fall, Johanna Jennifer Elisabeth; Trochta, John Tyler; Gondra, Jon Ruiz (IMR/PINRO Joint Report Series, Research report, 2023)

    • Age prediction by deep learning applied to Greenland halibut (Reinhardtius hippoglossoides) otolith images 

      Martinsen, Ivar; Harbitz, Alf; Bianchi, Filippo Maria (Peer reviewed; Journal article, 2022)
      Otoliths (ear-stones) in the inner ears of vertebrates containing visible year zones are used extensively to determine fish age. Analysis of otoliths is a time-consuming and difficult task that requires the education of ...

    • Automatic Fish Age Determination across Different Otolith Image Labs Using Domain Adaptation 

      Ordonez, Alba; Eikvil, Line; Salberg, Arnt-Børre; Harbitz, Alf; Elvarsson, Bjarki Thor (Peer reviewed; Journal article, 2022)
      The age determination of fish is fundamental to marine resource management. This task is commonly done by analysis of otoliths performed manually by human experts. Otolith images from Greenland halibut acquired by the ...

    • Automatic interpretation of otoliths using deep learning 

      Moen, Endre; Handegard, Nils Olav; Allken, Vaneeda; Albert, Ole Thomas; Harbitz, Alf; Malde, Ketil (Journal article; Peer reviewed, 2018)
      The age structure of a fish population has important implications for recruitment processes and population fluctuations, and is a key input to fisheries-assessment models. The current method of determining age structure ...

    • Effekten av nasjonale laksefjorder på risikoen for lakselusinfeksjon hos vill laksefisk langs norskekysten. Midtevaluering av ordningen med nasjonale laksefjorder 

      Bjørn, Pål Arne; Finstad, Bengt; Asplin, Lars; Johnsen, Ingrid Askeland; Nilsen, Rune; Serra-Llinares, Rosa Maria; Lindstrøm, Ulf; Helland, Ingeborg Palm; Berg, Marius; Harbitz, Alf (Rapport fra Havforskningen;Nr. 19-2013, Working paper, 2013)

    • Egga Nord 2013. Toktrapport fra Havforskningsinstituttets tokt med FF G.O. Sars 15.10.–2.11.13 

      Bergstad, Odd Aksel; Harbitz, Alf; Hansen, Hege Øverbø; Heggebakken, Lise; Wienerroither, Rupert; Kristiansen, Arve; Dahl, Martin; Kristiansen, Jarle (Toktrapport/Havforskningsinstituttet;Nr. 2 - 2013, Working paper, 2013)
      Since 1994 a depth stratified annual bottom trawl survey was conducted along the continental slope (68-80°N, 400-1500 m) using chartered factory trawlers. The main focus since the start of the series was to describe the ...

    • Explaining decisions of deep neural networks used for fish age prediction 

      Ordonez, Alba; Eikvil, Line; Salberg, Arnt-Børre; Harbitz, Alf; Murray, Sean Meling; Kampffmeyer, Michael (Peer reviewed; Journal article, 2020)
      Age-reading of fish otoliths (ear stones) is important for the sustainable management of fish resources. However, the procedure is challenging and requires experienced readers to carefully examine annual growth zones. In ...

    • Impacts of extreme weather events on transport infrastructure in Norway 

      Frauenfelder, Regula; Solheim, Anders; Isaksen, Ketil; Romstad, Bård; Dyrrdal, Anita Verpe; Ekseth, Kristine; Skaland, Reidunn Gangstø; Harbitz, Alf; Harbitz, Carl Bonnevie; Haugen, Jan Erik; Hygen, Hans Olav; Haakenstad, Hilde; Jaedicke, Christian; Jónsson, Árni; Klæboe, Ronny; Ludvigsen, Johanna; Meyer, Nele Kristin; Rauken, Trude; Sverdrup-Thygeson, Kjetil (Journal article, 2016)

    • Kvoteråd for vassildfiske i norsk sone i 2010 

      Hallfredsson, Elvar; Harbitz, Alf; Albert, Ole Thomas (Rapport fra Havforskningen;Nr.4-2009, Working paper, 2009-11)
      Anbefalinger: Det anbefales en totalkvote på 10.000 tonn for direkte fiske etter vassild nord for 62°N i 2010. Havforskningsinstitutet har ikke innvendinger mot bifangstregulering av vassild sør for 62°N.

    • Parameter-sparse modification of Fourier methods to analyse the shape of closed contours with application to otolith outlines 

      Harbitz, Alf (Journal article; Peer reviewed, 2016-02-05)
      Elliptical Fourier descriptors (EFDs) have been used extensively in shape analysis of closed contours and have a range of marine applications, such as automatic identification of fish species and discrimination between ...

    • Salmon lice infection on wild salmonids in marine protected areas: an evaluation of the Norwegian ‘National Salmon Fjords 

      Serra-Llinares, Rosa Maria; Bjørn, Pål Arne; Finstad, Bengt; Nilsen, Rune; Harbitz, Alf; Berg, Marius; Asplin, Lars (Journal article; Peer reviewed, 2014-02-05)
      In Norway, 29 fjords and 52 rivers have been designated for protection in order to prevent the infection of important populations of wild salmonids with salmon lice of farm origin. We evaluated the effect of this protection ...

    • Separation of Norwegian coastal cod and Northeast Arctic cod by otolith morphometry 

      Stransky, Christoph; Baumann, Hannes; Fevolden, Svein-Erik; Harbitz, Alf; Høie, Hans; Nedreaas, Kjell Harald; Salberg, Arnt-Børre; Skarstein, Tuula H. (ICES CM documents;2007/L:10, Working paper, 2007)
      For stock assessment purposes, Atlantic cod (Gadus morhua) from the coastal and offshore regions off northern Norway is usually allocated to Norwegian coastal cod (NCC) and Northeast Arctic cod (NEAC) by internal ...

    • Survey strategy for monitoring Norwegian deep-sea fish species 

      Harbitz, Alf; Planque, Benjamin; Hallfredsson, Elvar; Albert, Ole Thomas (Fisken og havet;8-2011, Research report, 2011-12-31)
      This document reports on the results of the project 13327 on establishing methods for the surveillance of deepwater resources. After a presentation of the project mandate and background information on past surveys and their ...

    • A two-dimensional geostatistic method to simulate the precision of abundance estimates 

      Aschan, Michaela; Harbitz, Alf (Journal article; Peer reviewed, 2003)
      In this paper, we outline a geostatistic method to simulate the relative precision (coefficient of variation, CV) of total abundance estimates of one species in a predetermined, stratified area when it is appropriate to ...

    • When acoustics is not enough – towards a measurement of sandeel availability 

      Johnsen, Espen; Harbitz, Alf (ICES CM documents;2009/I:16, Working paper, 2009)
      Experimental surveys in the peak feeding season of sandeel (April-May) show that the abundance and geographical distribution of schooling lesser sandeels (Ammodytes marinus) can be acoustically measured, but the density ...

    • Workshop på hydroakustiske undersøkelser i Norskehavet 

      Planque, Benjamin; Bethke, Eckhard; Drevetnyak, Konstantin; Harbitz, Alf; Nedreaas, Kjell Harald; Pedchenko, Andrey; Pedersen, Ronald; Skúvadal, Fróði; Zubov, Valery (Fisken og havet, Research report, 2009)
      This report presents the international redfish survey carried out in the Norwegian Sea in August 2008 and the methodology used to review and compare the different hydroacoustic scrutinizing procedures. The results of the ...