2024
Uncrewed surface vehicles (USVs) as platforms for fisheries and plankton acoustics
Nils Olav Handegard, Alex De Robertis, Arne Johannes Holmin, Espen Johnsen, Joshua Lawrence, Naig Le Bouffant, Richard O'driscoll, David Peddie, Geir Pedersen, Pierre Priou, Rabea Patricia Rogge, Mikal Arntzen Samuelsen, David A. Demer
ICES Journal of Marine Science
2024
Broadband backscattering by Atlantic herring (Clupea harengus L.) differs when measured from a research vessel vs. a silent uncrewed surface vehicle
Geir Pedersen, Espen Johnsen, Babak Khodabandeloo, Nils Olav Handegard
ICES Journal of Marine Science
2024
Oil droplet fouling on lesser sandeel (Ammodytes marinus) eggshells does not enhance the crude oil induced developmental toxicity
Elin Sørhus, Reidun Marie Bjelland, Caroline Durif, Espen Johnsen, Carey Donald, Sonnich Meier, Trond Nordtug, Frode Bendiksen Vikebø, Prescilla Perrichon
Journal of Hazardous Materials
468
2023
Early ontogeny of the lesser sandeel (Ammodytes marinus)
Prescilla Perrichon, Reidun Marie Bjelland, Caroline Durif, Ingrid Uglenes Fiksdal, Espen Johnsen, Anne Berit Skiftesvik, Alessandro Cresci, Howard Browman, Elin Sørhus
Developmental Dynamics
2023
WORKSHOP ON UNAVOIDABLE SURVEY EFFORT REDUCTION 2 (WKUSER2)
Sean C. Anderson, Nate Bacheler, Lewis Barnett, Casper Willestofte Berg, Kristan Blackhart, Derek Bolser, Patrik Börjesson, Meaghan Bryan, Thibault Cariou, Corina Chaves, Elizabeth Chilton, Jason Conner, Annica De Groote, Lukas DeFilippo, Paul Dolder, Catherine Foley, Hans Gerritsen, Madison Hall, Espen Johnsen, Eoghan Kelly, Stan Kotwicki, Sven Kupschus, Gwladys Lambert, Andy Lipsky, Emily Markowitz, Guillermo Martin, Angelia Miller, Coilin Minto, Bríd O'Connor, Kotaro Ono, Zack Oyafuso, Iosu Paradinas, Maria Grazia Pennino, Elizabeth Phillips, John Gabriel Ramirez, Yves Reecht, Paul Regular, Margaret Siple, Matt Siskey, David Stokes, Anna Stroh, James T. Thorson, Ralf van Hal, Joel Vigneau, Daniel Vilas, Kai Wieland, Semra Yalcin
ICES Scientific Reports
5
2022
Magnetic fields generated by the DC cables of offshore wind farms have no effect on spatial distribution or swimming behavior of lesser sandeel larvae (Ammodytes marinus)
Alessandro Cresci, Prescilla Perrichon, Caroline Durif, Elin Sørhus, Espen Johnsen, Reidun Marie Bjelland, Torkel Larsen, Anne Berit Skiftesvik, Howard Browman
Marine Environmental Research
176
2022
Kayak Drone – a silent acoustic unmanned surface vehicle for marine research
Atle Totland, Espen Johnsen
Frontiers in Marine Science
9
2021
Highly mixed impacts of near-future climate change on stock productivity proxies in the North East Atlantic
Olav Sigurd Kjesbu, Svein Sundby, Anne Britt Sandø, Maud Alix, Solfrid Sætre Hjøllo, Maik Tiedemann, Mette Skern-Mauritzen, Claudia Junge, Maria Fossheim, Cecilie Broms, Guldborg Søvik, Fabian Zimmermann, Kjell Harald Nedreaas, Elena Eriksen, Hannes Höffle, Ann Merete Hjelset, Cecilie Kvamme, Yves Reecht, Halvor Knutsen, Asgeir Aglen, Ole Thomas Albert, Erik Berg, Bjarte Bogstad, Caroline Durif, Kim Aleksander Tallaksen Halvorsen, Åge Sigurd Høines, Carsten Hvingel, Edda Johannesen, Espen Johnsen, Even Moland, Mari Skuggedal Myksvoll, Leif Nøttestad, Erik Joel Steinar Olsen, Georg Skaret, Jon Egil Skjæraasen, Aril Slotte, Arved Staby, Erling Kåre Stenevik, Jan Erik Stiansen, Martina H. Stiasny, Jan Henry Sundet, Frode Bendiksen Vikebø, Geir Huse
Fish and Fisheries
23
p. 601-615
2021
Killer whale movements on the Norwegian shelf are associated with herring density
Emma Vogel, Martin Biuw, Marie-Anne Blanchet, Ian D. Jonsen, Evert Mul, Espen Johnsen, Solfrid Sætre Hjøllo, Morten Tange Olsen, Rune Dietz, Audun Rikardsen
MEPS
2021
Predicting abundance indices in areas without coverage with a latent spatio-temporal Gaussian model
Olav Nikolai Breivik, Fredrik L Aanes, Guldborg Søvik, Asgeir Aglen, Sigbjørn Mehl, Espen Johnsen
ICES Journal of Marine Science
2020
In situ calibration of observatory broadband echosounders
Egil Ona, Guosong Zhang, Geir Pedersen, Espen Johnsen
ICES Journal of Marine Science
77
p. 2954-2959
2020
Long term acoustic time series of the Lofoten–Vesterålen ocean observatory
Geir Pedersen, Guosong Zhang, Ana Sofia Aniceto, Espen Johnsen
Journal of the Acoustical Society of America
148
2020
Video Image Enhancement and Machine Learning Pipeline for Underwater Animal Detection and Classification at Cabled Observatories
Vanesa Lopez-vazquez, Jose Manuel Lopez-guede, Simone Marini, Emanuela Fanelli, Espen Johnsen, J. Aguzzi
Sensors
20
p. 1-25
2020
in situ calibration of observatory broadband echosounders
Egil Ona, Guosong Zhang, Geir Pedersen, Espen Johnsen
ICES Journal of Marine Science
2020
Diel vertical movements determine spatial interactions between cod, pelagic fish and krill on an Arctic shelf bank
Georg Skaret, Geir Odd Johansen, Espen Johnsen, Johanna Jennifer Elisabeth Fall, Øyvind Fiksen, Gøran Englund, Per Fauchald, Harald Gjøsæter, Gavin Macaulay, Edda Johannesen
Marine Ecology Progress Series
638
p. 13-23
2020
Acoustic classification in multifrequency echosounder data using deep convolutional neural networks
Olav Brautaset, Anders Ueland Waldeland, Espen Johnsen, Ketil Malde, Line Eikvil, Arnt-Børre Salberg, Nils Olav Handegard
ICES Journal of Marine Science
77
p. 1391-1400
2020
Measurements of underwater noise radiated by commercial ships at a cabled ocean observatory
Guosong Zhang, Tonje Nesse Forland, Espen Johnsen, Geir Pedersen, Hefeng Dong
Marine Pollution Bulletin
153
2019
Underwater noise from wind at the high north LoVe ocean observatory
Lars Alf Ødegaard, Geir Pedersen, Espen Johnsen
p. 359-366
2019
StoX: An open source software for marine survey analyses
Espen Johnsen, Atle Totland, Åsmund Skålevik, Arne Johannes Holmin, Gjert Endre Dingsør, Edvin Fuglebakk, Nils Olav Handegard
Methods in Ecology and Evolution
10
p. 1523-1528
2019
Cabled ocean observatory data reveal food supply mechanisms to a cold-water coral reef
Tom Van Engeland, Olav Rune Godø, Espen Johnsen, Gerard C.A. Duineveld, Dick Van Oevelen
Progress in Oceanography
172
p. 51-64
2018
Multispecies acoustic dead-zone correction and bias ratio estimates between acoustic and bottom-trawl data
Kotaro Ono, Stan Kotwicki, Gjert Endre Dingsør, Espen Johnsen
ICES Journal of Marine Science
75
p. 361-373
2017
Collective structures anchor massive schools of lesser sandeel to the seabed, increasing vulnerability to fishery
Espen Johnsen, Guillaume Rieucau, Egil Ona, Georg Skaret
Marine Ecology Progress Series
573
p. 229-236
2016
Acoustic identification of marine species using a feature library
Rolf Korneliussen, Yngve Heggelund, Gavin Macaulay, Daniel Patel, Espen Johnsen, Inge Kristian Eliassen
Methods in oceanography
17
p. 187-205
2015
An evaluation of the bottom trawl surveys in the Benguela Current Large Marine Ecosystem
Bjørn Erik E Axelsen, Espen Johnsen
Fisheries Oceanography
24
p. 74-87
2014
Marine ecosystem acoustics (MEA): Quantifying processes in the sea at the spatio-temporal scales on which they occur
Olav Rune Godø, Nils Olav Handegard, Howard Browman, Gavin Macaulay, Stein Kaartvedt, Jarl Giske, Egil Ona, Geir Huse, Espen Johnsen
ICES Journal of Marine Science
71
p. 2357-2369
2014
A new model for simulating growth in fish
Johannes Hamre, Espen Johnsen, Kristin Hamre
PeerJ
2013
2013
Small-scale spatial structuring of burrowed sandeels and the catching properties of the dredge
Espen Johnsen, Alf Harbitz
ICES Journal of Marine Science
70
p. 379-386
2012
A robust method for generating separate catch time-series for each of the hake species caught in the Namibian trawl fishery
Espen Johnsen, J. Kathena
South African Journal of Marine Science
34
p. 43-53
2011
Foetal deformities in a smooth-hound shark, Mustelus mustelus, from an oil exploited area in Angola
Diana Zaera-Perez, Espen Johnsen
Cybium
35
p. 231-236
2009
Size-dependent frequency response of sandeel schools
Espen Johnsen, Ronald Pedersen, Egil Ona
ICES Journal of Marine Science
66
p. 1100-1105
2024
Identifying size and behavior of Mueller’s Pearlside (Maurolicus muelleri) by combining measured broadband frequency responses with backscattering models and in-trawl observations
Maria Tenningen, Geir Pedersen, Babak Khodabandeloo, Nils Olav Handegard, Tonje Nesse Forland, Thor A. Klevjer, Espen Johnsen
2024
Behaviour and platform dependent broadband backscattering by physostome fish (Clupea harengus L.) revisited
Geir Pedersen, Babak Khodabandeloo, Espen Johnsen, Nils Olav Handegard
2024
Testing acoustic data quality and performance on Sounder USV
Nils Olav Handegard, Arne Johannes Holmin, Espen Johnsen, Rolf Korneliussen, Geir Pedersen, Joakim Skjefstad, Rabea Patricia Rogge, Mikal Arntzen Samuelsen
2023
Action plan for implementing USV in acoustic trawl surveys. CRIMAC – Workshop on Fisheries acoustics and Uncrewed Surface Vehicles.
Johnsen, Espen
2023
Spatial structure and sensitivity of lesser sandeel to increasing pressure of human activities filling knowledge gaps and improved risk assessment : KnowSandeel 2.0
Elin Sørhus, Frode Bendiksen Vikebø, Espen Johnsen
2023
Tobis en nøkkelart -hvor sårbar er de ulike livsfasene hos tobis for menneskelig aktivitet i Nordsjøen og Norskekysten?
Elin Sørhus, Frode Bendiksen Vikebø, Espen Johnsen
2023
Towards a multi-platform armada strategy for ecosystem based marine surveys
Espen Johnsen, Nils Olav Handegard, Atle Totland, Arne Johannes Holmin, Cecilie Kvamme, Are Salthaug, Geir Huse
2023
Behaviour dependent broadband backscattering by physostomous fish (Clupea harengus L.)
Geir Pedersen, Nils Olav Handegard, Espen Johnsen
2022
Developing and deploying machine learning methods for acoustic data
Nils Olav Handegard, Olav Brautaset, Changkyu Choi, Tomasz Furmanek, Arne Johan Hestnes, Espen Johnsen, Alba Ordonez, Ingrid Utseth, Sindre Vatnehol, Geir Huse
2021
CRIMAC - Center for Research-based Innovation in Marine Acoustic Abundance Estimation and Backscatter Classification
Nils Olav Handegard, Tonje Nesse Forland, Espen Johnsen, Geir Pedersen, Maria Tenningen, Egil Ona
2019
Underwater noise from wind at the high north LoVe ocean observatory
Lars Alf Ødegaard, Geir Pedersen, Espen Johnsen
2019
Acoustic measurements of herring close to the sea surface
Espen Johnsen, Atle Totland, Rokas Kubilius, Egil Ona
2018
Sea2Data - from acquisition to advice
Sjur Ringheim Lid, Åge Fotland, Harald Gjøsæter, Espen Johnsen, Jens-Otto Krakstad, Helge Sagen, Edvin Fuglebakk, Nils Olav Handegard
2017
In situ study of the functional response of cod to capelin using broadband acoustics and trawl sampling
Georg Skaret, Johanna Jennifer Elisabeth Fall, Per Fauchald, Øyvind Fiksen, Harald Gjøsæter, Edda Johannesen, Geir Odd Johansen, Espen Johnsen, Gavin Macaulay
2016
Sea2Data - from data acquisition to advice
Sjur Ringheim Lid, Åge Fotland, Harald Gjøsæter, Espen Johnsen, Jens-Otto Krakstad, Helge Sagen, Thomas de Lange Wenneck, Nils Olav Handegard
2015
Increasing the precision in acoustic estimates of patchy distributed fish
Espen Johnsen, Egil Ona, Alf Harbitz, Hector Pena, Arne Johannes Holmin
2013
"StoX" - an open source approach to survey calculations
Atle Totland, Harald Gjøsæter, Nils Olav Handegard, Espen Johnsen, Sjur Ringheim Lid
2013
Variance and estimates of number of individuals from acoustic surveys
Knut Korsbrekke, Gjert Endre Dingsør, Espen Johnsen
2012
Kvoteutsiktene for de viktigste fiskeslagene de neste 5 årene
Ole Arve Misund, Bjarte Bogstad, tore Haug, Elvar H. Hallfredsson, Irene Huse, Carsten Hvingel, Åge Sigurd Høines, Randi Ingvaldsen, Espen Johnsen, Leif Nøttestad, Erling Kåre Stenevik, Sigurd Tjelmeland, Else Torstensen, Nils Inge Øien
2024
Fangstprøvelotteriet 2023 - erfaringer og resultat
Håkon Magne Otterå, Lise Heggebakken, Åge Sigurd Høines, Espen Johnsen, Cecilie Kvamme, Leif Nøttestad, Georg Skaret, Erling Kåre Stenevik, Bjørn Vidar Svendsen
Rapport fra havforskningen
2024
Fordeling og mengde av tobis i norsk sone av Nordsjøen i mai 2023 — Tobistokt i Nordsjøen 23. april – 13. mai 2023
Espen Johnsen, Hector Pena, Ronald Pedersen, Åse Husebø, Lisbet Solbakken
Toktrapport
2024
Foreløpig råd for tobisfiske i norsk økonomisk sone i 2024 - Faglig grunnlag
Espen Johnsen, Cecilie Kvamme
Rapport fra havforskningen
2024
Survey report for CRIMAC SFI 2023
Nils Olav Handegard, Vaneeda Allken, Arne Johannes Holmin, Espen Johnsen, Rolf Korneliussen, Geir Pedersen, Joakim Skjefstad, Rabea Patricia Rogge, Mikal Arntzen Samuelsen, Maria Tenningen, Lise Doksæter Sivle
Toktrapport
2023
Fangstprøvelotteriet 2022 - erfaringer og resultat
Georg Skaret, Justine Emmanuelle Diaz, Lise Heggebakken, Lea Marie Hellenbrecht, Åge Sigurd Høines, Espen Johnsen, Cecilie Kvamme, Leif Nøttestad, Are Salthaug, Erling Kåre Stenevik, Bjørn Vidar Svendsen, Susanne Tonheim, Håkon Magne Otterå
Rapport fra havforskningen
2023
Spatiotemporal variation in the growth and size distributions of lesser sandeel (Ammodytes marinus) in the north-eastern North Sea
Daniel Berge, Espen Johnsen, Maria Tenningen
2023
Toktrapport fra økosystemtokt i Vestlandsfjordene — Hydrografi, vannkjemi, reker, krill, bunnfisk, tobis og perifylla
Guldborg Søvik, Tone Falkenhaug, Fabian Zimmermann, Natalya Gallo, Kjell Harald Nedreaas, Jean-Baptiste Danre, Terje Hovland, Trude Hauge Thangstad, Siri Aaserud Olsen, Espen Johnsen, Lars Asplin
2023
Fangstprøvelotteriet 2021 - erfaringer og resultat
Åge Sigurd Høines, Justine Emmanuelle Diaz, Lise Heggebakken, Lea Marie Hellenbrecht, Espen Johnsen, Cecilie Kvamme, Leif Nøttestad, Are Salthaug, Georg Skaret, Erling Kåre Stenevik, Bjørn Vidar Svendsen, Susanne Tonheim, Håkon Magne Otterå
2023
Foreløpige råd for tobisfiskeriet i norsk økonomisk sone 2023
Johnsen, Espen
2023
Panel-based Assessment of Ecosystem Condition of the North Sea Shelf Ecosystem
Per Arneberg, Berengere Husson, Anna Siwertsson, Jon Albretsen, Knut Yngve Børsheim, Côme Denechaud, Joël Durant, Tone Falkenhaug, Per Fauchald, Anders Martin Frugård Opdal, Sissel Jentoft, Tore Johannessen, Espen Johnsen, Elizabeth Marie Jones, Cecilie Kvamme, Anna Jeja Gabriella Ljungström, Pål Buhl-Mortensen, Yves Reecht, Hiroko Kato Solvang, Morten D. Skogen, Aril Slotte, Espen Strand, Guldborg Søvik, Gro Ingleid van der Meeren
2023
Panel-based Assessment of Ecosystem Condition of the North Sea Shelf Ecosystem - Appendices
Per Arneberg, Berengere Husson, Anna Siwertsson, Jon Albretsen, Knut Yngve Børsheim, Côme Denechaud, Joël Durant, Tone Falkenhaug, Per Fauchald, Anders Martin Frugård Opdal, Sissel Jentoft, Tore Johannessen, Espen Johnsen, Elizabeth Marie Jones, Cecilie Kvamme, Anna Jeja Gabriella Ljungström, Pål Buhl-Mortensen, Yves Reecht, Hiroko Kato Solvang, Morten D. Skogen, Aril Slotte, Espen Strand, Guldborg Søvik, Gro Ingleid van der Meeren
2022
Fangstprøvelotteriet 2020 – erfaringer og resultat
Åge Sigurd Høines, Espen Johnsen, Cecilie Kvamme, Leif Nøttestad, Håkon Magne Otterå, Are Salthaug, Erling Kåre Stenevik, Bjørn Vidar Svendsen
2022
Råd for tobisfiskeriet i norsk sone for 2022 - Tobistokt i Nordsjøen 27. april-12. mai 2022
Johnsen, Espen
2022
CRIMAC - Annual Report 2021
Nils Olav Handegard, Geir Pedersen, Tonje Nesse Forland, Maria Tenningen, Espen Johnsen
2022
Spatiotemporal Variation in the Density Distribution of Sprat (Sprattus Sprattus) in Hardangerfjorden and Sognefjorden
Daniel Jarl Skåtøy Stiti, Espen Johnsen, Cecilie Kvamme, Arild Folkvord
2021
CRIMAC - Annual Report 2020
Egil Ona, Nils Olav Handegard, Geir Pedersen, Tonje Nesse Forland, Maria Tenningen, Espen Johnsen
2021
Kunnskapsstatus for havsil i norsk sone av Nordsjøen
Espen Johnsen, Elin Sørhus, Karen de Jong, Kai Kristoffer Lie, Bjørn Einar Grøsvik
2021
Fish diversity data from the Barents Sea Ecosystem Survey 2004-2019
Edda Johannesen, Rupert Wienerroither, Herdis Langøy Mørk, Berengere Husson, Arne Johannes Holmin, Espen Johnsen, Andrey Dolgov, Tatiana Prokhorova
2021
Final report for the REDUS project - Reduced Uncertainty in Stock Assessment
Erik Joel Steinar Olsen, Sondre Aanes, Magne Tommy Aldrin, Olav Nikolai Breivik, Edvin Fuglebakk, Daisuke Goto, Nils Olav Handegard, Cecilie Hansen, Arne Johannes Holmin, Daniel Howell, Espen Johnsen, Natoya Jourdain, Knut Korsbrekke, Kotaro Ono, Håkon Magne Otterå, Holly Ann Perryman, Samuel Subbey, Guldborg Søvik, Ibrahim Umar, Sindre Vatnehol, Jon Helge Vølstad
2021
CRIMAC cruise report 2020116
Egil Ona, Nils Olav Handegard, Espen Johnsen, Rokas Kubilius, Rolf Korneliussen, Geir Pedersen, Atle Totland, Shale Rosen, Melanie Underwood, Lars N Andersen, Ivar Wangen, Eirik Svoren Osborg
2020
Measuring distribution and density of sprat in Årdalsfjorden with a kayak drone - 15-16 August 2020
Espen Johnsen, Atle Totland, Cecilie Kvamme
2019
StoX applied to cod and haddock data from the Barents Sea NOR-RUS ecosystem cruise in autumn - Swept area abundance, length and weight at age 2004-2017
Edda Johannesen, Espen Johnsen, Geir Odd Johansen, Knut Korsbrekke
2018
Estimation of acoustic indices with CVs for cod and haddock in the Barents Sea winter survey 1994 – 2017 applying the Sea2Data StoX software.
Sigbjørn Mehl, Asgeir Aglen, Espen Johnsen, Åsmund Skålevik
2018
Estimation of acoustic indices with CVs for Northeast Arctic saithe in the Norwegian coastal survey 2003-2017 applying the Sea2Data StoX software.
Sigbjørn Mehl, Espen Johnsen, Åsmund Skålevik, Asgeir Aglen
2016
Re-estimation of swept area indices with CVs for main demersal fish species in the Barents Sea winter survey 1994-2016 applying the Sea2Data StoX software
Sigbjørn Mehl, Asgeir Aglen, Espen Johnsen
2016
Tobis ved Vestlandet og i Nordsjøen 1950-1990
Magnus Tangen, Johannes Hamre, Espen Johnsen, Odd Nakken, Kjell Harald Nedreaas, Øyvind Tangen, Per Ågotnes
2015
Makrellen er en velsignelse for verden og økosystemene
Leif Nøttestad, Espen Johnsen, Kjell Rong Utne
2014
Assessments for management of living marine resources in the Barents Sea and adjacent waters – a focus on methodology The 16th Russian-Norwegian Symposium Sochi, Russia, 10-12 September 2013
Knut Sunnanå, Yuri A. Kovalev, Harald Gjøsæter, Espen Johnsen, Evgeny Shamray