2017
 

Remote electronic monitoring and the landing obligation – some insights into fishers’ and fishery inspectors’ opinions

År: 2017

Remote electronic monitoring and the landing obligation – some insights into fishers’ and fishery inspectors’ opinions

Schreiber Plet-Hansen, K., Qvist Eliasen, S., Mortensen, L. O., Bergsson, H., Olesen, H. J. & Ulrich, C. 2017 In : Marine Policy. 76, p. 98-106

Publication: Research - peer-reviewJournal article – Annual report year: 2016

The European fisheries management is currently undergoing a fundamental change in the handling of catches of commercial fisheries with the implementation of the 2013 Common Fisheries Policy. One of the main objectives of the policy is to end the practice of discarding in the EU by 2019. However, for such changes to be successful, it is vital to ensure stakeholders acceptance, and it is prudent to consider possible means to verify compliance with the new regulation. Remote Electronic Monitoring (REM) with Closed-Circuit Television (CCTV) has been tested in a variety of fisheries worldwide for different purposes and is currently considered as one possible tool to ensure compliance with a European ban on discards. This study focuses on Danish fishery inspectors and on fishers with REM experience, whose opinions are less
well known. Their views on the landing obligation and on the use of REM were investigated using interviews and questionnaires, and contrasted to some fishers without REM experience. 80% of fishery inspectors and 58% of
REM-experienced fishers expressed positive views on REM. 9 out of 10 interviewed fishers without REM experience were against REM. Participation in a REM trial has not led to antipathy towards REM. Fishery inspectors saw on-board observers, at-sea control and REM as the three best solutions to control the landing obligation but shared the general belief that the landing obligation cannot be enforced properly and will be difficult for fishers to comply with. The strengths and weaknesses of REM in this context are discussed
Original languageEnglish
JournalMarine Policy
Volume76
Pages (from-to)98-106
ISSN0308-597X
DOIs
StatePublished - 2017

 

Development and test of selective sorting grids used in the Norway lobster (Nephrops norvegicus) fishery

År: 2017

Development and test of selective sorting grids used in the Norway lobster (Nephrops norvegicus) fishery

Madsen, N., Holst, R., Frandsen, R. & Hansen, K. 2017 In : Fisheries Research. 185, p. 26-33

Publication: Research - peer-reviewJournal article – Annual report year: 2016

Due to generally high discard rates in Norway lobster (Nephrops norvegicus) fisheries, a discard ban coming up and to the cod recovery plan in several areas, selective sorting grids have been tested in many areas and are specified by legislation for use in the Kattegat and Skagerrak area bordering Norway, Denmark and Sweden. Grids are very selective, but they can lead to loss of landable Norway lobster and valuable fish species. To improve retention of these species, we developed three new grids using made by polyurethane to make them flexible: One grid had horizontal bars, one had vertical bars, and one had vertical bars and a guiding funnel in front of the grid. Four unselective net bags were used to collect the catch escaping through different parts of the grid or escaping without passing through the grid. Water flow around the grid bars was measured in a flume tank. The three grids were tested from a commercial trawler in the Kattegat and Skagerrak area. Underwater filming was conducted to assess grid performance and fish behavior. Results showed that a bottom hole in the lower part of the grid allowed species in the lower part of the gear to pass and retained in the bag behind the hole. More flatfish passed the grid with horizontal bars compared to that with vertical bars, but the retention rate was still low. Use of the guiding funnel increased the contact with the grid considerably for both target and unwanted species. In all three grid designs, there were losses of Norway lobster above minimum landing size.
Original languageEnglish
JournalFisheries Research
Volume185
Pages (from-to)26-33
ISSN0165-7836
DOIs
StatePublished - 2017

 

Codend selectivity in a commercial Danish anchor seine

År: 2017

Codend selectivity in a commercial Danish anchor seine

Noack, T., Frandsen, R., Krag, L. A., Mieske, B. & Madsen, N. 2017 In : Fisheries Research. 186, p. 283-291

Publication: Research - peer-reviewJournal article – Annual report year: 2016

tDanish seining (or anchor seining) is a fishing technique that is gaining increasing attention because itis considered to be a fuel-efficient fishing method with low environmental impact. However, scientificdocumentation of the selectivity characteristics of Danish seines is lacking, and the gear generally isgrouped with bottom trawls and Scottish seines in fisheries management legislation. In this study, wedeveloped a codend cover to estimate the selectivity of a standard commercial Danish seine codendfor four fish species. The data for the dominant species, dab (Limanda limanda) and plaice (Pleuronectesplatessa), was best described by models that combine two or three logistic models, which indicated thatmore than one selection process was at work. Selectivity of cod (Gadus morhua) was best described by aRichard curve and selectivity of red gurnard (Chelidonichthys lucernus) by a logistic curve. The estimatedselectivity curve of dab indicated, contrary to cod and plaice, low retention of individuals below MLS.Confidence limits for larger length classes of cod and red gurnard were relatively wide. For plaice, theestimated selection factor, which is the length with 50% retention divided by mesh size, was comparableto literature values from trawl studies. The average value for cod was similar for Danish and Scottishseines, but lower for trawls. The results are discussed in the context of fisheries management with focuson the landing obligation of the new Common Fisheries Policy
Original languageEnglish
JournalFisheries Research
Volume186
Pages (from-to)283-291
ISSN0165-7836
DOIs
StatePublished - 2017

 

Sensitivity of a tropical micro-crustacean (Daphnia lumholtzi) to trace metals tested in natural water of the Mekong River

År: 2017

Sensitivity of a tropical micro-crustacean (Daphnia lumholtzi) to trace metals tested in natural water of the Mekong River

Dao, T-S., Le, V-N., Bui, B-T., Dinh, K. V., Wiegand, C., Dao, C-T., To, T-H., Nguyen, L-S-P. & Vo, T-M-C. 2017 In : Science of the Total Environment. 574, p. 1360-1370

Publication: Research - peer-reviewJournal article – Annual report year: 2016

Original languageEnglish
JournalScience of the Total Environment
Volume574
Pages (from-to)1360-1370
ISSN0048-9697
DOIs
StatePublished - 2017

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Pike (Esox lucius L.) on the edge: consistent individual movement patterns in transitional waters of the western Baltic

År: 2017

Pike in the western Baltic Sea live on the edge of their salinity tolerance. Under physiologically challenging conditions, organism may respond by moving to environmentally more benign areas during critical periods, such as during spawning. We hypothesised that pike in a brackish lagoon (8–10 ppt salinity) would perform spawning- and feeding-related movements between areas with different salinity regimes. Twenty-two pike were caught prior to spawning, tagged with acoustic transmitters, and their movements were tracked for 18 months. Pike showed two main patterns of movements that were consistent within individuals across two years. Whereas some individuals stayed in the lagoon year-round, most pike left the lagoon for longer periods after spawning and returned to the lagoon prior to following year’s spawning season. We found no evidence that probability of moving out of the lagoon co-varied with either length or condition factor. Despite the fact that the lagoon’s salinity is close to the reported upper limit for pike egg development, results indicated that all pike spawned in the lagoon. Correspondingly, genetic data showed that all fish belonged to the same reproductive population unit. Movement patterns thus appear to reflect individual variation in home-range and/or resource optimisation following ideal free principles.
Original languageEnglish
JournalHydrobiologia
Volume784
Issue number1
Pages (from-to)143–154
ISSN0018-8158
DOIs
StatePublished - 2017