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Jesse Brinkhof - One of the best experts on this subject based on the ideXlab platform.
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bycatch reduction in the deep water Shrimp pandalus borealis trawl Fishery with a large mesh top panel
Journal for Nature Conservation, 2021Co-Authors: Kristine Cerbule, Nadine Jacques, Bent Herrmann, Roger B. Larsen, Jesse Brinkhof, Hermann Pettersen, Olafur Ingolfsson, Eduardo Grimaldo, Manu Berrondo SistiagaAbstract:Abstract 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 investigated were Greenland halibut (Reinhardtius hippoglossoides), redfish (Sebastes spp.) and polar cod (Boreogadus saida). The bycatch of Greenland halibut and the smallest polar cod was significantly reduced, while no effect was found for redfish. The large mesh panel did not lead to a significant loss of deep-water Shrimp. The results of this study illustrate how a simple modification of a fishing gear can mitigate the bycatch problem in a Shrimp Fishery, without significant losses of the target species.
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Can a large-mesh sieve panel replace or supplement the Nordmøre grid for bycatch mitigation in the northeast Atlantic deep-water Shrimp Fishery?
Fisheries Research, 2019Co-Authors: Nadine Jacques, Bent Herrmann, Roger B. Larsen, Manu Berrondo Sistiaga, Jure Brčić, Gökhan Gökçe, Jesse BrinkhofAbstract:Abstract The Nordmore 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 (Pandalus borealis) Fishery, where the use of a Nordmore grid is mandatory. In this Fishery, redfish (Sebastes spp.) and polar cod (Boreogadus saida) are two common bycatch species. Redfish is a commercially important species that at times is captured in great numbers, whereas polar cod is a threatened species that can also be caught in high numbers. Sieve panels are bycatch reduction devices commonly used in Shrimp fisheries and their potential to replace or supplement the Nordmore grid in the Northeast Atlantic deep-water Shrimp Fishery is of interest. We investigated the size selectivity of redfish, polar cod and deep-water Shrimp for the Nordmore grid and four sieve panel configurations differing in mesh size (182 and 286 mm) and inclination angle (10 and 20°). The sieve panels were unable to replace the Nordmore grid as a stand-alone device due to greater catches of the bycatch species. However, combining the two devices provided promising results. Specifically, when a large-mesh sieve panel was placed in front of the Nordmore grid, 20–40% fewer small redfish and polar cod in a specific size range entered the codend, while the loss of targeted Shrimp was less than 5%.
Herrmann Bent - One of the best experts on this subject based on the ideXlab platform.
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Bycatch reduction in the deep-water Shrimp (Pandalus borealis) trawl Fishery with a large mesh top panel
'Elsevier BV', 2021Co-Authors: Cerbule Kristine, Sistiaga Manu, Jacques Nadine, Herrmann Bent, Larsen, Roger B., Brinkhof Jesse, Grimaldo Eduardo, Pettersen Hermann, Ingólfsson, Ólafur Arnar, Lilleng DagfinnAbstract: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 investigated were Greenland halibut (Reinhardtius hippoglossoides), redfish (Sebastes spp.) and polar cod (Boreogadus saida). The bycatch of Greenland halibut and the smallest polar cod was significantly reduced, while no effect was found for redfish. The large mesh panel did not lead to a significant loss of deep-water Shrimp. The results of this study illustrate how a simple modification of a fishing gear can mitigate the bycatch problem in a Shrimp Fishery, without significant losses of the target species.publishedVersio
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The efficacy of illumination to reduce bycatch of eulachon and groundfishes before trawl capture in the eastern North Pacific ocean Shrimp Fishery
NRC Research Press (a division of Canadian Science Publishing), 2019Co-Authors: Lomeli, Mark J. M., Herrmann Bent, Groth, Scott D., Blume, Matthew T.o., Wakefield W. WaldoAbstract:This study examined the extent that eulachon (Thaleichthys pacificus) and groundfishes escape trawl entrainment in response to artificial illumination along an ocean Shrimp (Pandalus jordani) trawl fishing line. Using a double-rigged trawler, we compared the catch efficiencies for ocean Shrimp, eulachon, and groundfishes between an unilluminated trawl and a trawl illuminated with 5 green LEDs along its fishing line. Results showed a significant reduction in the bycatch of eulachon and yellowtail rockfish (Sebastes flavidus) in the presence of LED illumination. As eulachon are an Endangered Species Act listed species, this finding provides valuable information for Fishery managers implementing recovery plans and evaluating potential Fishery impacts on their recovery and conservation. For other rockfishes (Sebastes spp.) and flatfishes, however, we did not see the same effect as the illuminated trawl caught similarly or significantly more fishes than the unilluminated trawl. Prior to this research, the extent that eulachon and groundfishes escape trawl capture in response to illumination along an ocean Shrimp trawl fishing line was unclear. Our study has provided results to fill that data gap.The accepted manuscript in pdf format is listed with the files at the bottom of this page. The presentation of the authors' names and (or) special characters in the title of the manuscript may differ slightly between what is listed on this page and what is listed in the pdf file of the accepted manuscript; that in the pdf file of the accepted manuscript is what was submitted by the author
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Can a large-mesh sieve panel replace or supplement the Nordmøre grid for bycatch mitigation in the northeast Atlantic deep-water Shrimp Fishery?
'Elsevier BV', 2019Co-Authors: Jacques Nadine, Herrmann Bent, Larsen, Roger B., Sistiaga, Manu Berrondo, Brčić Jure, Gökçe Gökhan, Brinkhof JesseAbstract:Source at https://doi.org/10.1016/j.fishres.2019.105324. 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 (Pandalus borealis) Fishery, where the use of a Nordmøre grid is mandatory. In this Fishery, redfish (Sebastes spp.) and polar cod (Boreogadus saida) are two common bycatch species. Redfish is a commercially important species that at times is captured in great numbers, whereas polar cod is a threatened species that can also be caught in high numbers. Sieve panels are bycatch reduction devices commonly used in Shrimp fisheries and their potential to replace or supplement the Nordmøre grid in the Northeast Atlantic deep-water Shrimp Fishery is of interest. We investigated the size selectivity of redfish, polar cod and deep-water Shrimp for the Nordmøre grid and four sieve panel configurations differing in mesh size (182 and 286 mm) and inclination angle (10 and 20°). The sieve panels were unable to replace the Nordmøre grid as a stand-alone device due to greater catches of the bycatch species. However, combining the two devices provided promising results. Specifically, when a large-mesh sieve panel was placed in front of the Nordmøre grid, 20–40% fewer small redfish and polar cod in a specific size range entered the codend, while the loss of targeted Shrimp was less than 5%
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Can a large-mesh sieve panel replace or supplement the Nordmore grid for bycatch mitigation in the northeast Atlantic deep-water Shrimp Fishery?
'Elsevier BV', 2019Co-Authors: Jacques Nadine, Sistiaga Manu, Herrmann Bent, Larsen, Roger B., Brčić Jure, Gökçe Gökhan, Brinkhof JesseAbstract:WOS: 000488300900026The Nordmore 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 (Pcmdalus borealis) Fishery, where the use of a Nordmore grid is mandatory. In this Fishery, redfish (Sebastes spp.) and polar cod (Boreogadus saida) are two common bycatch species. Redfish is a commercially important species that at times is captured in great numbers, whereas polar cod is a threatened species that can also be caught in high numbers. Sieve panels are bycatch reduction devices commonly used in Shrimp fisheries and their potential to replace or supplement the Nordmore grid in the Northeast Atlantic deep-water Shrimp Fishery is of interest. We investigated the size selectivity of redfish, polar cod and deep-water Shrimp for the Nordmare grid and four sieve panel configurations differing in mesh size (182 and 286 mm) and inclination angle (10 and 20 degrees). The sieve panels were unable to replace the Nordmore grid as a stand-alone device due to greater catches of the bycatch species. However, combining the two devices provided promising results. Specifically, when a large-mesh sieve panel was placed in front of the Nordmore grid, 20-40% fewer small redfish and polar cod in a specific size range entered the codend, while the loss of targeted Shrimp was less than 5%.UiT, The Arctic University of Norway in Tromso; Norwegian Seafood Research Fund [901303]We thank the crew of RV "Helmer Hanssen" and assistants Ivan Tatone, Ilmar Brinkhof, Hermann Pettersen, Maria Alquiza Madina and Gyda Christophersen for valuable assistance on board. We are grateful to UiT, The Arctic University of Norway in Tromso and the Norwegian Seafood Research Fund (grant 901303) for funding the experiments carried out in this study. Finally, we thank the editor and the two anonymous reviewers, who we believe have improved our manuscript significantly with their comments
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The Efficacy of Illumination to Reduce Bycatch of Eulachon and Groundfishes Before Trawl Capture in the Eastern North Pacific Ocean Shrimp Fishery
'Canadian Science Publishing', 2019Co-Authors: Lomeli, Mark J. M., Herrmann Bent, Groth, Scott D., Blume Matthew, Wakefield W. WaldoAbstract:This study examined the extent that eulachon (Thaleichthys pacificus) and groundfishes escape trawl entrainment in response to artificial illumination along an ocean Shrimp (Pandalus jordani) trawl fishing line. Using a double-rigged trawler, we compared the catch efficiencies for ocean Shrimp, eulachon, and groundfishes between an unilluminated trawl and a trawl illuminated with 5 green LEDs along its fishing line. Results showed a significant reduction in the bycatch of eulachon and yellowtail rockfish (Sebastes flavidus) in the presence of LED illumination. As eulachon are an Endangered Species Act listed species, this finding provides valuable information for Fishery managers implementing recovery plans and evaluating potential Fishery impacts on their recovery and conservation. For other rockfishes (Sebastes spp.) and flatfishes, however, we did not see the same effect as the illuminated trawl caught similarly or significantly more fishes than the unilluminated trawl. Prior to this research, the extent that eulachon and groundfishes escape trawl capture in response to illumination along an ocean Shrimp trawl fishing line was unclear. Our study has provided results to fill that data gap.acceptedVersio
Elena Guijarro Garcia - One of the best experts on this subject based on the ideXlab platform.
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the northern Shrimp pandalus borealis offshore Fishery in the northeast atlantic
Advances in Marine Biology, 2007Co-Authors: Elena Guijarro GarciaAbstract:This chapter describes the development and current situation of the offshore Shrimp fisheries in Iceland, Greenland, Svalbard, Jan Mayen and the Norwegian Barents Sea area, with information on the biology of Pandalus borealis and its relation to the environment. Some additional information about the inshore Shrimp fisheries of Iceland and Greenland of relevance to this study is also included. The Icelandic offshore Shrimp Fishery started in 1975 and has formed between 68% and 94% of the annual catch of Shrimp since 1984. Landings peaked at 66,000 tons in 1997. The offshore fleet increased threefold from 1983 to 1987, and catch per unit of effort doubled. The first signs of overfishing were detected in 1987, when the first total allowable catch (TAC) was set, and catches decreased during the next few years despite the discovery of new fishing grounds. Good recruitment allowed catches to rise steadily from 1990 to 1996. However, catches and stock index have decreased markedly since then, with a minimum catch for the period 1998–2003 of 21,500 tons in 2000. It has been suggested that predation by cod is an important factor affecting Shrimp stock size, but mortality from predation is slightly lower than fishing mortality, so that the impact of fishing cannot be disregarded. The Greenland offshore Shrimp Fishery is one of the largest in the North Atlantic and it generates 90% of the export value of the country. The Fishery started in 1970 in West Greenland with landings of 1200 tons, but since 1974 it has formed between 59% and 89% of the annual Shrimp catch. In 2004, landings reached 113,000 tons and the fishable stock was estimated at 300,000 tons. The significant spatial expansion of the Fishery from the original fishing grounds off the Disko Island area to all of the West coast south of 75°N and the fleet improvement over the past three decades have made possible this spectacular growth. Other fishing grounds off the East coast have been fished since 1978, mostly by foreign vessels. Catches in this area oscillated between 5000 and 15,000 tons during the period 1980–2004. The main problem of the Shrimp Fishery in Greenland is its overlapping with nursery areas of redfish, Greenland halibut, cod and other groundfish species, some of which show declining trends of biomass and abundance. This led to the implementation in 2000 of sorting grids and laws that forbid fishing when the bycatch exceeds legal limits. However, it is likely that ecological processes only partially understood, such as the trophic web and hydrography of the area, greatly influence the stock abundance of the demersal community. The offshore Norwegian Fishery started in 1973. The main fishing grounds are off Svalbard and in the Barents Sea. Catches at Jan Mayen have never exceeded 5% of the total annual catch of northern Shrimp. Large fluctuations in catches and stock size are the main characteristic of this Fishery. Stock size seems to be largely dependent on the annual hydrographic variability in the area and trends in abundance of predator species, especially cod. However, Shrimp mortality due to predation has been estimated to be the same as fishing mortality, and therefore fishing probably accounts for part of the observed variability in stock size. Large populations of juvenile cod, haddock, redfish and Greenland halibut are often found on the Shrimp fishing grounds. The implementation of sorting grids in 1991 and a bio‐economical model in 1993 to estimate allowable maximum catches of the commercial bycatch species have not solved the bycatch problem. All the commercial fish species present on the Shrimp grounds are currently below safe biological limits. This is the only Fishery within the studied area that is not regulated by means of a TAC system.
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the northern Shrimp pandalus borealis offshore Fishery in the northeast atlantic
Advances in Marine Biology, 2007Co-Authors: Elena Guijarro GarciaAbstract:This chapter describes the development and current situation of the offshore Shrimp fisheries in Iceland, Greenland, Svalbard, Jan Mayen and the Norwegian Barents Sea area, with information on the biology of Pandalus borealis and its relation to the environment. Some additional information about the inshore Shrimp fisheries of Iceland and Greenland of relevance to this study is also included. The Icelandic offshore Shrimp Fishery started in 1975 and has formed between 68% and 94% of the annual catch of Shrimp since 1984. Landings peaked at 66,000 tons in 1997. The offshore fleet increased threefold from 1983 to 1987, and catch per unit of effort doubled. The first signs of overfishing were detected in 1987, when the first total allowable catch (TAC) was set, and catches decreased during the next few years despite the discovery of new fishing grounds. Good recruitment allowed catches to rise steadily from 1990 to 1996. However, catches and stock index have decreased markedly since then, with a minimum catch for the period 1998-2003 of 21,500 tons in 2000. It has been suggested that predation by cod is an important factor affecting Shrimp stock size, but mortality from predation is slightly lower than fishing mortality, so that the impact of fishing cannot be disregarded. The Greenland offshore Shrimp Fishery is one of the largest in the North Atlantic and it generates 90% of the export value of the country. The Fishery started in 1970 in West Greenland with landings of 1200 tons, but since 1974 it has formed between 59% and 89% of the annual Shrimp catch. In 2004, landings reached 113,000 tons and the fishable stock was estimated at 300,000 tons. The significant spatial expansion of the Fishery from the original fishing grounds off the Disko Island area to all of the West coast south of 75 degrees N and the fleet improvement over the past three decades have made possible this spectacular growth. Other fishing grounds off the East coast have been fished since 1978, mostly by foreign vessels. Catches in this area oscillated between 5000 and 15,000 tons during the period 1980-2004. The main problem of the Shrimp Fishery in Greenland is its overlapping with nursery areas of redfish, Greenland halibut, cod and other groundfish species, some of which show declining trends of biomass and abundance. This led to the implementation in 2000 of sorting grids and laws that forbid fishing when the bycatch exceeds legal limits. However, it is likely that ecological processes only partially understood, such as the trophic web and hydrography of the area, greatly influence the stock abundance of the demersal community. The offshore Norwegian Fishery started in 1973. The main fishing grounds are off Svalbard and in the Barents Sea. Catches at Jan Mayen have never exceeded 5% of the total annual catch of northern Shrimp. Large fluctuations in catches and stock size are the main characteristic of this Fishery. Stock size seems to be largely dependent on the annual hydrographic variability in the area and trends in abundance of predator species, especially cod. However, Shrimp mortality due to predation has been estimated to be the same as fishing mortality, and therefore fishing probably accounts for part of the observed variability in stock size. Large populations of juvenile cod, haddock, redfish and Greenland halibut are often found on the Shrimp fishing grounds. The implementation of sorting grids in 1991 and a bio-economical model in 1993 to estimate allowable maximum catches of the commercial bycatch species have not solved the bycatch problem. All the commercial fish species present on the Shrimp grounds are currently below safe biological limits. This is the only Fishery within the studied area that is not regulated by means of a TAC system.
Nadine Jacques - One of the best experts on this subject based on the ideXlab platform.
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bycatch reduction in the deep water Shrimp pandalus borealis trawl Fishery with a large mesh top panel
Journal for Nature Conservation, 2021Co-Authors: Kristine Cerbule, Nadine Jacques, Bent Herrmann, Roger B. Larsen, Jesse Brinkhof, Hermann Pettersen, Olafur Ingolfsson, Eduardo Grimaldo, Manu Berrondo SistiagaAbstract:Abstract 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 investigated were Greenland halibut (Reinhardtius hippoglossoides), redfish (Sebastes spp.) and polar cod (Boreogadus saida). The bycatch of Greenland halibut and the smallest polar cod was significantly reduced, while no effect was found for redfish. The large mesh panel did not lead to a significant loss of deep-water Shrimp. The results of this study illustrate how a simple modification of a fishing gear can mitigate the bycatch problem in a Shrimp Fishery, without significant losses of the target species.
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Can a large-mesh sieve panel replace or supplement the Nordmøre grid for bycatch mitigation in the northeast Atlantic deep-water Shrimp Fishery?
Fisheries Research, 2019Co-Authors: Nadine Jacques, Bent Herrmann, Roger B. Larsen, Manu Berrondo Sistiaga, Jure Brčić, Gökhan Gökçe, Jesse BrinkhofAbstract:Abstract The Nordmore 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 (Pandalus borealis) Fishery, where the use of a Nordmore grid is mandatory. In this Fishery, redfish (Sebastes spp.) and polar cod (Boreogadus saida) are two common bycatch species. Redfish is a commercially important species that at times is captured in great numbers, whereas polar cod is a threatened species that can also be caught in high numbers. Sieve panels are bycatch reduction devices commonly used in Shrimp fisheries and their potential to replace or supplement the Nordmore grid in the Northeast Atlantic deep-water Shrimp Fishery is of interest. We investigated the size selectivity of redfish, polar cod and deep-water Shrimp for the Nordmore grid and four sieve panel configurations differing in mesh size (182 and 286 mm) and inclination angle (10 and 20°). The sieve panels were unable to replace the Nordmore grid as a stand-alone device due to greater catches of the bycatch species. However, combining the two devices provided promising results. Specifically, when a large-mesh sieve panel was placed in front of the Nordmore grid, 20–40% fewer small redfish and polar cod in a specific size range entered the codend, while the loss of targeted Shrimp was less than 5%.
Hans Polet - One of the best experts on this subject based on the ideXlab platform.
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on electrical fishing for brown Shrimp crangon crangon i laboratory experiments
Fisheries Research, 2005Co-Authors: Hans Polet, Fernand Delanghe, Reinhart VerschooreAbstract:Abstract The Fishery for brown Shrimp ( Crangon crangon ) in the North Sea is carried out by more than 600 vessels with total annual brown Shrimp landings of around 20,000 t. Due to the small mesh size used, the catches also contain large amounts of unwanted by-catch. To find ways of reducing this by-catch, experiments were carried out with electric pulses. The basic idea was to selectively invoke a startle response with Shrimp without stimulating any by-catch species. A selective groundrope could then be used in combination with electric pulses to obtain catch separation. As a preparation for sea trials, laboratory experiments were carried out. The pulse generators were tested for their basic characteristics. Experiments were carried out with fish and invertebrate species that are frequently caught in the brown Shrimp Fishery. The effect of pulse amplitude and frequency in relation to ambient parameters on the response of these animals was tested. To assess the effect of the pulses on these animals, survival experiments were carried out. The main conclusion was that Shrimps react strongly to the pulses and most of the other species regularly caught in Shrimp trawls do not, so selective electro-fishing has potential. The survival tests indicated that the pulses have no effect on the survival and general behaviour of the animals that have been in the electric field.
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selectivity experiments with sorting grids in the north sea brown Shrimp crangon crangon Fishery
Fisheries Research, 2002Co-Authors: Hans PoletAbstract:Abstract The Fishery for brown Shrimp (Crangon crangon) is important in the North Sea and is carried out by more than 600 vessels, with total annual brown Shrimp landings of around 20,000 t. Due to the small mesh size used the catches also contain large amounts of by-catch. To find ways of reducing this by-catch, experiments were carried out with a Nordmφre type sorting grid during two trips on a research vessel and three trips on a commercial vessel. The results depended strongly on the catch composition in the brown Shrimp Fishery. If the catch composition did not cause clogging problems with the sorting grid, it met the objectives it was designed for. The reduction of fish (>70%) and benthos (65%) in the catch was quite high. The commercial brown Shrimp catch was reduced by 15%. The cod-end catch consisted mainly of Shrimps and required less sorting and the cod-end selectivity for Shrimp increased. If, however, material occurred in the catch that caused clogging, the commercial brown Shrimp catch was soon below the level acceptable to commercial fishermen.
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codend and whole trawl selectivity of a Shrimp beam trawl used in the north sea
Fisheries Research, 2000Co-Authors: Hans PoletAbstract:In preparation of a by-catch reduction program for the Belgian brown Shrimp Fishery, a study was carried out on the codend and whole trawl selectivity of the beam trawl widely used in this Fishery. The codend cover technique was used to determine the codend selectivity, whereas the whole trawl selectivity was estimated using small mesh pockets attached to several positions on the body of the net. Codend selectivity for Shrimp proved to be very variable and was significantly influenced by clogging of the meshes, catch volume and state of the sea. The L50 for Shrimp, for all hauls combined, was 39.4 mm and the selection factor 1.82 for a mesh size of 21.7 mm. The selection range was 11.6 mm. The selectivity of the net body was quite important and allowed more Shrimps to escape than the codend did. It was mainly the rounded lateral part of the belly that contributed to this selectivity. Due to the small mesh size, the codend selectivity for flatfish was very poor. The selectivity of the net body for flatfish was negligible.
