• Accounting for Uncertainties in Biodiversity Estimations: A New Methodology and Its Application to the Mesopelagic Sound Scattering Layer of the High Arctic 

      Herrmann, Bent; Cerbule, Kristine; Brčić, Jure; Grimaldo Vela, Eduardo Enrique; Geoffroy, Maxime; Daase, Malin; Berge, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-04-27)
      Measures of biological diversity (biodiversity) are important for monitoring the state of ecosystems. Several indices and methods are used to describe biodiversity from field observations. Marine faunal biodiversity is often quantified based on analysis of samples collected using a trawl during research surveys. To monitor spatial and temporal changes in biodiversity between surveys, samples are ...
    • Bycatch reduction in the deep-water shrimp (Pandalus borealis) trawl fishery by increasing codend mesh openness 

      Jacques, Nadine; Cerbule, Kristine; Pettersen, Hermann; Herrmann, Bent; Ingólfsson, Ólafur; Sistiaga, Manu Berrondo; Larsen, Roger B.; Brinkhof, Jesse; Grimaldo, Vela Eduardo; Brčić, Jure; Lilleng, Dagfinn (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-08-03)
      In most trawl fisheries, drag forces tend to close the meshes in large areas of diamond mesh codends, negatively affecting their selective potential. In the Barents Sea deep-water shrimp (Pandalus borealis) trawl fishery, selectivity is based on a sorting grid followed by a diamond mesh codend. However, the retention of juvenile fish as well as undersized shrimp is still a problem. In this study, ...
    • Bycatch reduction in the deep-water shrimp (Pandalus borealis) trawl fishery with a large mesh top panel 

      Cerbule, Kristine; Jacques, Nadine; Pettersen, Hermann; Ingólfsson, Ólafur Arnar; Herrmann, Bent; Grimaldo, Eduardo; Larsen, Roger B.; Brinkhof, Jesse; Sistiaga, Manu; Lilleng, Dagfinn; Brčić, Jure (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-04-08)
      In the Northeast Atlantic deep-water shrimp (Pandalus borealis) trawl fishery, the bycatch of juvenile fish and shrimp represents a problem. This study evaluated if inserting a 200 mm mesh size top-panel in the last three sections of the tapered upper belly section of the trawl could reduce bycatch of juveniles while maintaining the catch efficiency for deep-water shrimp. The bycatch species ...
    • Can biodegradable materials reduce plastic pollution without decreasing catch efficiency in longline fishery? 

      Cerbule, Kristine; Grimaldo, Eduardo; Herrmann, Bent; Larsen, Roger B.; Brčić, Jure; Vollstad, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-03-23)
      Longlining is a widely used fishing method. During longline fishing, some of the snoods connecting the hooks to the mainline are often lost at sea. Since snoods are made of nylon or polyester, lost snoods contribute to marine plastic pollution. Replacing nylon or polyester with a new material made of biodegradable plastics can potentially reduce macro- and microplastic pollution that is caused by ...
    • Can vertical separation of species in trawls be utilized to reduce bycatch in shrimp fisheries? 

      Larsen, Roger B.; Herrmann, Bent; Brcic, Jure; Sistiaga, Manu; Cerbule, Kristine; Nielsen, Kåre Nolde; Jacques, Nadine; Lomeli, Mark Joseph Max; Tokac, Adnan; Cuende, Elsa (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-03-26)
      Several shrimp trawl fisheries use a Nordmöre sorting grid to avoid bycatch of fish. However, small fish can pass through the grid. Therefore, the retention of juvenile fish often remains an issue during shrimp trawling. We investigated the vertical distribution of deepwater shrimp (<i>Pandalus borealis</i>) and dominant bycatch species at the point where the Nordmöre grid section is installed. This ...
    • Comparison of physical properties and fishing performance between biodegradable PLA and conventional PA trammel nets in grey mullet (Mugil cephalus) and red-lip mullet (Liza haematocheila) fishery 

      Yu, Mengjie; Tang, Yanli; Min, Minghua; Herrmann, Bent; Cerbule, Kristine; Liu, Changdong; Dou, Yilin; Zhang, Liyou (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-09-16)
      Marine plastic pollution and continuous capture of marine animals, so-called “ghost fishing”, by abandoned, lost, or otherwise discarded fishing gear (ALDFG) are global concerns. This study investigated whether biodegradable polylactic acid (PLA) monofilaments can be used to replace conventionally used non-biodegradable polyamide (PA) in trammel net fishery for limiting ALDFG associated effects. It ...
    • Comparison of the efficiency and modes of capture of biodegradable versus nylon gillnets in the Northeast Atlantic cod (Gadus morhua) fishery 

      Cerbule, Kristine; Herrmann, Bent; Grimaldo, Eduardo; Larsen, Roger B.; Savina, Esther; Vollstad, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-04-01)
      Modern gillnets are usually made of nylon with high breaking strength, suitable elasticity and durability making them an efficient fishing gear. Lost, abandoned, or discarded gillnets at sea cause plastic pollution and can continue capturing marine animals over long periods of time. Biodegradable materials are being developed to replace nylon in gillnets. However, biodegradable gillnets have shown ...
    • Does soak time influence the effect of artificial light on catch efficiency in snow crab (Chionoecetes opilio) pot fishery? 

      Cerbule, Kristine; Herrmann, Bent; Grimaldo, Eduardo; Grimsmo, Leif; Karlsen, Junita D. (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-12-09)
      In the Barents Sea commercial snow crab (Chionoecetes opilio) fishery, an increase in catch efficiency of the conical pots is important for the profitability of the industry. Light emitting diodes (LEDs) have previously been tested for increasing catch efficiency of the snow crab pots. These earlier experiments have shown varying results ranging from large increase in snow crab catches to no ...
    • Effect of artificial lights on catch efficiency and capture patterns in Asian paddle crab (Charybdis japonica) gillnet fishery 

      Yu, Mengjie; Herrmann, Bent; Cerbule, Kristine; Liu, Changdong; Zhang, Liyou; Tang, Yanli (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-22)
      The gillnet fishery targeting Asian paddle crab (Charybdis japonica) is an important commercial fishery in the Yellow Sea of China. However, low catch rates represent a challenge, and solutions for improving the catch efficiency are crucial for economical sustainability in this fishery. Therefore, we tested whether the use of artificial fishing lights could improve gillnet catch performance. ...
    • The effect of long-term use on the Catch efficiency of Biodegradable gillnets 

      Grimaldo, Eduardo; Herrmann, Bent; Jacques, Nadine; Kubowicz, Stephan; Cerbule, Kristine; Su, Biao; Larsen, Roger B.; Vollstad, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-05)
      The effect of long-term use on the catch efficiency of biodegradable gillnets was investigated during commercial fishing trials and in controlled lab aging tests. The relative catch efficiency between biodegradable and nylon gillnets was evaluated over three consecutive fishing seasons for Atlantic cod (Gadus morhua) in Norway. The biodegradable gillnets progressively lost catch efficiency over time, ...
    • Effect of the Nordmøre grid bar spacing on size selectivity, catch efficiency and bycatch of the Barents Sea Northern shrimp fishery 

      Larsen, Roger B.; Herrmann, Bent; Sistiaga, Manu; Brinkhof, Jesse; Cerbule, Kristine; Grimaldo Vela, Eduardo Enrique; Lomeli, Mark JM (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-27)
      The introduction of the Nordmøre grid in shrimp trawls has reduced the bycatch of non-target species. In the Norwegian Northern shrimp (Pandalus borealis) fishery, the mandatory selective gear consists of a Nordmøre grid with 19 mm bar spacing combined with a 35 mm mesh size diamond mesh codend. However, fish bycatch in shrimp trawls remains a challenge and further modifications of the gear that ...
    • The effect of white and green LED-lights on the catch efficiency of the Barents Sea snow crab (Chionoecetes opilio) pot fishery 

      Cerbule, Kristine; Herrmann, Bent; Grimaldo, Vela Eduardo; Grimsmo, Leif; Vollstad, Jørgen (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-10-05)
      In commercial snow crab (Chionoecetes opilio) fishery, the catch efficiency of the conical pots is important for increasing the profitability of the industry. This study evaluated the effect of adding green and white light emitting diodes (LED) on the catch efficiency of commercially used conical pots. The results from the field experiments showed that inserting artificial lights significantly ...
    • Ghost fishing efficiency by lost, abandoned or discarded pots in snow crab (Chionoecetes opilio) fishery 

      Cerbule, Kristine; Herrmann, Bent; Grimaldo, Eduardo; Brinkhof, Jesse; Sistiaga, Manu; Larsen, Roger B.; Bak-Jensen, Zita (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-07-07)
      Marine pollution by lost, abandoned or otherwise discarded fishing gear (ALDFG) often has negative impact on the ecosystem through plastic pollution and continuous capture of marine animals, so-called “ghost fishing”. ALDFG in pot fisheries is associated with high ghost fishing risk. The snow crab (Chionoecetes opilio) pot fishery is conducted in harsh weather conditions increasing the risk of ...
    • Gillnet colour affects catch efficiency in pearlspot (Etroplus suratensis) tropical estuary fishery 

      Cerbule, Kristine; Madhu, V.R.; Mohanan, Salini; Herrmann, Bent (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-10-19)
      Gillnets are one of the most commonly used fishing gears in both marine and inland waters. Different colour filament nettings are often used in gillnets. However, the effect of gillnet colour on catch efficiency is unclear for most fisheries. Therefore, in this study we investigated the effect of gillnet colour on the catch efficiency in pearlspot (Etroplus suratensis) fishery in Vembanad lake, ...
    • Impact of ground gear design on catch efficiency in demersal trawl fishery 

      Fakıoğlu, Y.E.; Gökçe, G.; Özbilgin, H.; Cerbule, Kristine; Herrmann, Bent (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-03)
      The choice of ground gear design in demersal trawls can significantly affect both catch composition and efficiency. The preference for a specific design depends on the fishing ground. In the North-Eastern Mediterranean, two types of ground gears, Single Line and Double Line are commonly used. Therefore, this study compared the catch performance for trawls using these ground gears during research ...
    • Improved bycatch reduction in the mixed demersal trawl fishery for Norway pout (Trisopterus esmarkii) 

      Grimaldo, Eduardo; Brinkhof, Jesse; Herrmann, Bent; Cerbule, Kristine; Grimsmo, Leif; Pettersen, Hermann (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-12-22)
      In this study, we compared the bycatch reduction capacity of a trawl fitted with a standard rigid sorting grid with that of a trawl fitted with a newly developed, flexible system called the Excluder. We conducted the fishing trials in the Norway pout (Trisopterus esmarkii) small-meshed trawl fishery in the North Sea. Catch data were analysed by species and length using the catch comparison and catch ...
    • Increasing sustainability in food production by using alternative bait in snow crab (Chionoecetes opilio) fishery in the barents sea 

      Cerbule, Kristine; Grimsmo, Leif; Herrmann, Bent; Grimaldo, Eduardo (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-17)
      The use of food grade wild-captured species as bait for other fisheries questions the sustainability of food production. In pot fisheries, bait is an important factor determining the effectiveness of the gear. In snow crab (Chionoecetes opilio) fishery, the pots are normally baited with squid (Illex sp.) and herring (Clupea harengus). This fishery uses substantial amounts of bait for each ...
    • Is there a limit to the potential effects of shortening lastridge ropes on the size selectivity of diamond mesh codends? 

      Sistiaga, Manu; Herrmann, Bent; Brinkhof, Jesse; Larsen, Roger B.; Santos, Juan; Stepputtis, Daniel; Brinkhof, Ilmar; Jacques, Nadine; Cerbule, Kristine; Petetta, Andrea; Cuende, Elsa; Kvalvik, Liz Beate Kolstad (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-02-21)
      Shortening codend lastridge ropes can be an effective fishing gear modification to improve the size selection properties in diamond mesh codends. Lastridge ropes attached to codend selvedges withstand the longitudinal forces created by the catch building up and therefore, prevent the codend meshes from closing. However, the extent to which the lastridge ropes should be shortened to maximize the ...
    • The Legal Regime Applicable to Migrant Smuggling 

      Cerbule, Kristine (Master thesis; Mastergradsoppgave, 2015-09-01)
      The number or migrants that are smuggled to coastal states is increasing last years with emergence of new trends such as usage of large crewless cargo vessels for transportation of people. This thesis analyses whether it is possible to deal with the increasing number of migrant smuggling cases by sea within the existing framework of the law of the sea. After examination of provisions of the Law of ...
    • Modelling the effect of mesh size and opening angle on size selection and capture pattern in a snow crab (Chionoecetes opilio) pot fishery 

      Herrmann, Bent; Grimaldo, Eduardo; Brcic, Jure; Cerbule, Kristine (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-12-18)
      Size selection in commercial snow crab (Chionoecetes opilio) pot fisheries is important for reducing on-board sorting and unintended mortality of undersized individuals. In this paper, we tested whether snow crab of various sizes geometrically could pass through diamond meshes of different sizes and opening angles, to estimate a model for predicting the effect of mesh size and mesh opening angle on ...