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, ...

Trawlers targeting Deep-water Shrimp (<i>Pandalus borealis</i>) in the North Atlantic use a Nordmøre sorting grid ahead of a small-meshed codend. Based on experimental fishing, the effect of adding a 9 mm spaced release grid behind the mandatory 19 mm spaced Nordmøre sorting grid, was determined. The performance in terms of size selection of the release grid and the two grids combined were assessed ...

The Nordmøre grid is the principle bycatch mitigation device in many shrimp trawl fisheries. However, in several of these fisheries, bycatch is a problem because small sized fish can pass through the grid and enter the codend together with the targeted shrimp. One such fishery is the Northeast Atlantic deep-water shrimp (<i>Pandalus borealis</i>) fishery, where the use of a Nordmøre grid is mandatory. ...

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 ...

<p><i>Rationale</i>: Intrinsic biogeochemical markers, such as stable isotope ratios of carbon, nitrogen and sulphur, are increasingly used to trace the trophic ecology of marine top predators. However, insufficient knowledge of fractionation processes in tissues continues to hamper the use of these markers.</p> <p><i>Methods</i>: We performed a controlled feeding experiment with eight juvenile ...

Vertebral coalescence and malformation in the lateral line are reported in a specimen of cultured cyprinid fish <i>Hypophthalamichthys nobilis </i>. Severe vertebral fusion was observed and described. Lateral line showed unusual undulation in the trunk region. Genetic and epigenetic causes may be implicated in these anomalies.

The catch efficiency of two types of groundgear—a conventional rockhopper and a new type of groundgear called the semicircular spreading gear (SCSG)—was investigated through experimental fishing for Haddock Melanogrammus aeglefinus conducted in the Barents Sea. A retainer bag was attached behind the footrope of the trawl, and the number of fish that were overrun by the trawl was compared with the ...

Catch-based aquaculture (CBA) is an important production system in many parts of the world, especially in developing countries. In Norway CBA is based on capture and storage/farming of mature, North-east Atlantic (NEA) cod (Gadus morhua). The objective is to reduce seasonal variations and add value, by storing/farming fish to take advantage of higher prices in low seasons. Despite numerous development ...

Three known bromophenols, 2,3-dibromo-4,5-dihydroxybenzylaldehyde (1), 2,2′,3-tribromo-3′,4,4′,5-tetrahydroxy 6′-hydroxymethyldiphenylmethane (2) and bis(2, 3-dibromo-4,5-dihydroxylbenzyl) ether (3), and one new one, 5,5″-oxybis(methylene)bis (3-bromo-4-(2′,3′-dibromo-4′,5′-dihydroxylbenzyl)benzene-1,2-diol) (4), were isolated from an extract of the red alga, Vertebrata lanosa. The antioxidant ...

Change in oceanographic conditions causes structural alterations in marine fish communities, but this effect may go undetected as most monitoring programs until recently mainly have focused on oceanography and commercial species rather than on whole ecosystems. In this paper, the objective is to describe the spatial and temporal changes in the Barents Sea fish community in the period 1992–2004 while ...