Gyrodactylus triglopsi n. sp. (Monogenea: Gyrodactylidae) from the Gills of Triglops nybelini Jensen, 1944 (Teleostei: Cottidae) in the Barents Sea

Introduction Monogeneans of the genus Gyrodactylus were found on the gills of specimens of the bigeye sculpin Triglops nybelini Jensen, 1944 caught by trawl in the Barents Sea in January–February 2016. Methods Morphological preparations of the parasites were examined and photographed under a microscope at magnifications of × 100–1000 and morphometric analyses were carried out on 22 specimens using ImageJ2 software. Eight of the specimens used for the morphological comparisons were also subjected to molecular analyses by sequencing a region of the ribosomal DNA spanning partial 18S, the internal transcribed spacers 1 and 2 (ITS1 and 2), 5.8S and partial 28S and comparing this with other species through a BlastN-search in GenBank and through phylogenetic analyses. Results The morphology of the species from T. nybelini was markedly different to that of any of other species of Gyrodactylus. It is characterized by having relatively long hamulus roots, a character that it shares with two other species described from marine sculpins (Cottidae); G. armatus and G. maculosi. It also has a narrow rectangular ventral bar membrane with a posterior notch which it shares with G. maculosi only. Compared with all the seven species from marine Cottidae described so far, it has the smallest opisthaptoral hard parts. A comparison of the internal transcribed spacer (ITS) rDNA sequence with available sequences in GenBank and a phylogenetic analyses also showed it to be highly divergent from other sequences. Therefore, a new species is proposed, Gyrodactylus triglopsi n. sp. Conclusion Both the morphological and molecular analyses support the status of G. triglopsi as a new species. This is to our knowledge the first species of Gyrodactylus described from Triglops nybelini and the description extends the list of Gyrodactylus species found on fish in the Barents Sea to 17.publishedVersio

International Bottom Trawl Survey Working Group (IBTSWG). ICES Scientific Reports, 04:65

The International Bottom Trawl Survey Working Group (IBTSWG) coordinates fishery-independent bottom trawl surveys in the ICES area in the Northeast Atlantic and the North Sea. These long-term monitoring surveys provide data for stock assessments and facilitate examina-tion of changes in fish distribution and relative abundance. The group also promotes the stand-ardization of fishing gears and methods as well as survey coordination. This report summarizes the national contributions in 2021–2022 and plans for the 2022–2023 surveys coordinated by IBTSWG

The Third Workshop on Population of the RDBES Data Model (WKRDB-POP3)

The aims of this workshop were to explain the data model developed for the commercial fisheries Regional Database and Estimation System (RDBES), assist in populating it with real data for the second test data call for the RDBES, and encourage participants to take part in ongoing testing of the RDBES data submission system. This report documents the progress that participants have done to prepare their institutes for future use of the RDBES system. Some issues with data conversion have been identified and are documented in this report. None of the identified issues are thought to be serious impediments to moving forward with the RDBES development according to the roadmap decided by the Steering Committee of the Regional Fisheries Database in 2020. The RDBES Core Group (the group of people developing the RDBES data model) and ICES Data Centre will look at the results of this workshop and either respond to individual questions or adapt the data model and documentation as required. The workshop concluded and reported before the deadline of the test data call. For a complete test of the data model, all participants were encouraged to complete the data call. A report on the degree of completion of the data call may be expected from WGRDBESGOV which convenes after the data call deadline

Parasites of Northeast Arctic cod (Gadus morhua) in the Barents Sea: effects on reproduction

Parasites play a key role in the biodiversity and dynamics of an ecosystem, either by affecting host mortality and/or host reproduction. Spawning comes with a great cost in time and energy, and in times of poor conditions this time and energy is better directed into growth and survival to increase future success. The phenomenon of skipped spawning, where sexually mature fish skip a reproductive event, is a common occurence in the NEAC. Previous studies suggest that as much as 24-30% of females skip annual spawning, and instead remain at the feeding grounds. The causes for this is still unclear but it seems to occur in response to poor condition. As parasites, by definiton, have a negative effect on host fitness it is of finterest to see if parasites could affect the decision to skip spawning. In this study, we explore the effects of parasites on reproductive parameters in the Northeast Arctic cod (NEAC), the largest cod stock in the world. By comparing intensity of infestation in skippers and spawners we found that parasites do not seem to have an effect on the reproductive abilities of the NEAC. No significant differences in parasite intensity could be detected between skippers and spawners in any of the species included in our study. Nor were there any evidence to show that increase in parasite intensity were associated with decreased fecundity. Even an attempt to look at the effects of the whole parasite community by applying an intensity rank index did not find any correlation between infestation and reproductive parameters. However, caution must be made when making conclusions about parasites effect on host population dynamics. This demonstrates the importance of experimental studies of relationships between parasites and reproductive success. As well as look at parasite-induced host mortality in NEAC

Parasites of Northeast Arctic cod (Gadus morhua) in the Barents Sea: effects on reproduction

Parasites play a key role in the biodiversity and dynamics of an ecosystem, either by affecting host mortality and/or host reproduction. Spawning comes with a great cost in time and energy, and in times of poor conditions this time and energy is better directed into growth and survival to increase future success. The phenomenon of skipped spawning, where sexually mature fish skip a reproductive event, is a common occurence in the NEAC. Previous studies suggest that as much as 24-30% of females skip annual spawning, and instead remain at the feeding grounds. The causes for this is still unclear but it seems to occur in response to poor condition. As parasites, by definiton, have a negative effect on host fitness it is of finterest to see if parasites could affect the decision to skip spawning. In this study, we explore the effects of parasites on reproductive parameters in the Northeast Arctic cod (NEAC), the largest cod stock in the world. By comparing intensity of infestation in skippers and spawners we found that parasites do not seem to have an effect on the reproductive abilities of the NEAC. No significant differences in parasite intensity could be detected between skippers and spawners in any of the species included in our study. Nor were there any evidence to show that increase in parasite intensity were associated with decreased fecundity. Even an attempt to look at the effects of the whole parasite community by applying an intensity rank index did not find any correlation between infestation and reproductive parameters. However, caution must be made when making conclusions about parasites effect on host population dynamics. This demonstrates the importance of experimental studies of relationships between parasites and reproductive success. As well as look at parasite-induced host mortality in NEAC

Alternative materialer til plast brukt i snurrevadtau og trålmatter

Dette prosjektet studerte ulike løsninger for å redusere effekten av slitasje fra fossilbasert, ikke-nedbrytbare plastmaterialer som brukes i snurrevad og trålmatter. Prosjektet testet ulike natur-, syntetiske og biologisk nedbrytbare materialer i laboratorium og i felt. Prosjektet kvantifiserte og sannsynliggjorde hvor mye reduksjon i utslipp ulike tiltak og løsninger kan bidra med. Det inkluderes en vurdering av kostnad og økonomiske konsekvenser ved ulike tiltak og alternative materialer. Prosjektet ble gjennomført i samarbeid mellom SINTEF Ocean, UiT Norges arktiske universitet og SALT. Industripartnere Tustern AS og Hermes AS bidro med egeninnsats i form av tid og fartøytid. Prosjektet ble finansiert av FHF og Fiskeridirektoratet gjennom tilskudd til fiskeriforskning.FHF, FiskeridektoratetpublishedVersio

Alternative materialer til plast brukt i snurrevadtau og trålmatter

Source at https://www.sintef.no/.Dette prosjektet studerte ulike løsninger for å redusere effekten av slitasje fra fossilbasert, ikke-nedbrytbare plastmaterialer som brukes i snurrevad og trålmatter. Prosjektet testet ulike natur-, syntetiske og biologisk nedbrytbare materialer i laboratorium og i felt. Prosjektet kvantifiserte og sannsynliggjorde hvor mye reduksjon i utslipp ulike tiltak og løsninger kan bidra med. Det inkluderes en vurdering av kostnad og økonomiske konsekvenser ved ulike tiltak og alternative materialer. Prosjektet ble gjennomført i samarbeid mellom SINTEF Ocean, UiT Norges arktiske universitet og SALT. Industripartnere Tustern AS og Hermes AS bidro med egeninnsats i form av tid og fartøytid. Prosjektet ble finansiert av FHF og Fiskeridirektoratet gjennom tilskudd til fiskeriforskning

Gyrodactylus triglopsi n. sp. (Monogenea: Gyrodactylidae) from the Gills of Triglops nybelini Jensen, 1944 (Teleostei: Cottidae) in the Barents Sea

Introduction Monogeneans of the genus Gyrodactylus were found on the gills of specimens of the bigeye sculpin Triglops nybelini Jensen, 1944 caught by trawl in the Barents Sea in January–February 2016. Methods Morphological preparations of the parasites were examined and photographed under a microscope at magnifications of × 100–1000 and morphometric analyses were carried out on 22 specimens using ImageJ2 software. Eight of the specimens used for the morphological comparisons were also subjected to molecular analyses by sequencing a region of the ribosomal DNA spanning partial 18S, the internal transcribed spacers 1 and 2 (ITS1 and 2), 5.8S and partial 28S and comparing this with other species through a BlastN-search in GenBank and through phylogenetic analyses. Results The morphology of the species from T. nybelini was markedly different to that of any of other species of Gyrodactylus. It is characterized by having relatively long hamulus roots, a character that it shares with two other species described from marine sculpins (Cottidae); G. armatus and G. maculosi. It also has a narrow rectangular ventral bar membrane with a posterior notch which it shares with G. maculosi only. Compared with all the seven species from marine Cottidae described so far, it has the smallest opisthaptoral hard parts. A comparison of the internal transcribed spacer (ITS) rDNA sequence with available sequences in GenBank and a phylogenetic analyses also showed it to be highly divergent from other sequences. Therefore, a new species is proposed, Gyrodactylus triglopsi n. sp. Conclusion Both the morphological and molecular analyses support the status of G. triglopsi as a new species. This is to our knowledge the first species of Gyrodactylus described from Triglops nybelini and the description extends the list of Gyrodactylus species found on fish in the Barents Sea to 17

Gyrodactylus triglopsi n. sp. (Monogenea: Gyrodactylidae) from the Gills of Triglops nybelini Jensen, 1944 (Teleostei: Cottidae) in the Barents Sea

Introduction Monogeneans of the genus Gyrodactylus were found on the gills of specimens of the bigeye sculpin Triglops nybelini Jensen, 1944 caught by trawl in the Barents Sea in January–February 2016. Methods Morphological preparations of the parasites were examined and photographed under a microscope at magnifications of × 100–1000 and morphometric analyses were carried out on 22 specimens using ImageJ2 software. Eight of the specimens used for the morphological comparisons were also subjected to molecular analyses by sequencing a region of the ribosomal DNA spanning partial 18S, the internal transcribed spacers 1 and 2 (ITS1 and 2), 5.8S and partial 28S and comparing this with other species through a BlastN-search in GenBank and through phylogenetic analyses. Results The morphology of the species from T. nybelini was markedly different to that of any of other species of Gyrodactylus. It is characterized by having relatively long hamulus roots, a character that it shares with two other species described from marine sculpins (Cottidae); G. armatus and G. maculosi. It also has a narrow rectangular ventral bar membrane with a posterior notch which it shares with G. maculosi only. Compared with all the seven species from marine Cottidae described so far, it has the smallest opisthaptoral hard parts. A comparison of the internal transcribed spacer (ITS) rDNA sequence with available sequences in GenBank and a phylogenetic analyses also showed it to be highly divergent from other sequences. Therefore, a new species is proposed, Gyrodactylus triglopsi n. sp. Conclusion Both the morphological and molecular analyses support the status of G. triglopsi as a new species. This is to our knowledge the first species of Gyrodactylus described from Triglops nybelini and the description extends the list of Gyrodactylus species found on fish in the Barents Sea to 17

Gyrodactylus triglopsi n. sp. (Monogenea: Gyrodactylidae) from the Gills of Triglops nybelini Jensen, 1944 (Teleostei: Cottidae) in the Barents Sea

Monogeneans of the genus Gyrodactylus were found on the gills of specimens of the bigeye sculpin Triglops nybelini Jensen, 1944 caught by trawl in the Barents Sea in January–February 2016