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This report describes a demonstration trial of a single-rig, demersal whitefish ‘Rockhopper’ trawl constructed entirely of T90 or ‘turned mesh’ netting. This is the first time that T90 technology has been used in this way in the UK. The trawl used for this trial was designed and constructed by Icelandic trawl manufacturer, Fjardanet which has been pioneering this technology for a number of years. Descriptions of the fishing gear used are included. The report describes some background to the development work and the concept of T90 technology. Eight days of commercial fishing trials were carried out in January 2008 using the Shetland based vessel Mizpah operating on local fishing grounds about 50 miles NE of Lerwick. Despite being hampered by poor weather a total of 21 hauls were completed. The aim of the trials was to evaluate the performance of the T90 trawl with reference to fuel savings as a result of the reduced netting drag associated with this technology. This was done by measuring the main gear performance parameters and comparing them with those of the vessel’s existing gear of the same general dimensions. Some catch sampling was undertaken to examine other reported attributes of T90 trawls such improved catch rates, size selection and catch quality. From a gear performance perspective the T90 trawl compared well with the vessel’s own trawl. The information gathered on the fuel efficiency aspects of the gear however did not show any significant benefits from the T90 trawl despite indications that the netting drag had been considerably reduced, (~20%). The findings from the catch data were inconclusive. There were some indications of larger size ranges of some species being caught and retained by the T90 trawl but the findings did not appear to bear out the findings and experiences of the Icelandic fishermen to the same extent. There was more loss of marketable size grades of some species, particularly whiting associated with the T90 trawl. This was thought to be as a result of the more consistent mesh opening noted throughout the T90 trawl. The positive side of this was that there were no discards recorded. There was no noticeable difference in catch quality detected. The results showed that the combination of the T90 trawl fitted with a conventional diamond mesh codend of the same mesh size produced the best commercial results. The results were insufficient to draw any firm conclusions on the overall effectiveness of the T90 trawl and a number of proposals for further work have been highlighted.

This interim report is submitted to Seafish as part of the assignment titled ‘A review of the services provided by Seafish in relation to the UK aquaculture industry’. The preparation of this report represents Deliverable 3 of the assignment. The structure and content of the report is based on previous agreement between the contractor and the client as presented in the inception report. The contractors seek review, comments and approval from Seafish on this interim report.

Sea trials were carried out to compare a single trawl constructed of Dyneema Ultra Cross knotless netting to that of one constructed of Polyethylene (PE) knotted netting. During the instrumented trials out of Peterhead measurements, of all the basic parameters of both trawls were recorded as well as total gear drag and net drag. Drag reductions of approximately 10% were recorded, this should result in a possible 10% fuel saving. The dyneema net was found to be taking up a different shape in the water. The Harvest Hope is underatking long term fishing trials on the trawl.

The report analyses the trends in marine casualties and the lives of fishermen up to 1985. Two clear trends emerge. Vessels covered by the 1975 Fishing Vessels (Safety Provisions) rules are apparently experiencing as much as 38% reduction in total or serious casualties. Vessels generally under 12m not covered by the rules show an alarming increase in losses. The published data is not wholly satisfactory and measures are being taken to obtain more facts on accidents and causes.

The first aim of this project was to examine and gain a better understanding of the aggressive behaviour of the animals. Aggressive behaviour, causing injury or death, is thought to be a major obstacle in keeping animals in communal tanks. It was found that the Norway lobsters are able to build a dominance hierarchy, which reduces overall aggression in communal tanks. Moreover, it was found that pheromones are necessary for establishing dominance. Follow up studies will aim to gain a better understanding of the role of aggression in natural behaviour including territoriality,resource competition and mate choice. The second aim is to develop economic holding conditions for the animals. Holding animals in communal tanks is thought to be easier to manage - in terms of feeding and maintaining good water quality - than keeping them separately. Ongoing experiments comparing holding conditions indicate that there seems to be no difference in survival rate between individual and communal holding conditions. The third aim is to decide upon the best methods of collecting eggs and to hatch them. This will be researched in the next two years. Eggs will be collected by catching berried females. Holding conditions will be tested to maximize the hatching rate of the four larval stages in the lab. The results of the study will improve the understanding of the species which could help drive better stock management. In addition, it could support the fishing industry by providing sustainability and reducing the influence of natural barriers to fishing, such as weather conditions.

This report evaluates and recommends different economic analysis methods for comparing the value of industry sectors and informing policy questions about allocation of resources to achieve efficiency or fairness of distribution.

Clean supplies of water are essential for the industry to maintain high standards of hygiene and quality. Where seawater is used, regulations demand that the water is free from microbiological contamination and that disinfection is carried out where required. In an operation such as shrimp processing where the product is cooled in seawater, cross contamination as a result of using contaminated seawater may result in food poisoning. It is thought that seawater containing a disinfectant residual may also be used to slow the microbiological spoilage of the product itself. For example using treated water in an RSW system may improve fish quality and extend shelf life. A series of practical trials were carried out to determine the effectiveness of electrolytic ionization, UV irradiation and chlorination for killing bacteria in seawater, with a view to the development of a commercial system for use on shrimp boats. A trial was also carried out to determine the effect on white fish quality of using ionized water in an RSW system. All treatments except chlorination using sodium hypochlorite proved to be unsuitable due to poor bacteriocidal performance and/or prohibitive costs. Sodium hypochlorite gave effective coliform bacterial kills at dose levels as low as 5 mg/1 of chlorine. A marginal improvement in quality was determined over a 7 day period with treated RSW versus untreated RSW.

This report details a series of laboratory trials which follow on from initial work reported in SR498. Trials were carried out to determine the effect of sodium hypochlorite and ozone on the quality of cod and mackerel in refrigerated seawater (RSW). In addition, trials were carried out to determine the effect of ozone on boxed and iced fish, held in a gas flushed hold or chill store. The rate at which ozone naturally decayed to a safe level was also determined, along with the effectiveness of ozone as a surface disinfectant. A trial was also carried out to determine the level of ozone in the hold of a fishing vessel fitted with an ozone generator, during a fishing trip.

Polycylic aromatic hydrocarbons (PaH's) form a large group of chemicals, some of which are known to be toxic. They are produced largely by combustion processes and are present in smoked foods. The European Commission is proposing a maximum permitted limit of 5ppb for the PaH benzo(a) pyrene (BaP) in smoked foods. To determine the potential impact of this, Seafish has carried out a survey of the size and nature of the fish smoking industry in the UK and has gathered representative samples of its products for analysis. The survey found the value of smoked fish production in the UK to be over £120 million per annum. A wide variety of products are produced from a range of fish species using modern and traditional kilns, smoked over a variety of woods. PaH analyses of 33 products showed them all to be well within the proposed EU limit of 5ppb for BaP. Only 2 products exceeded 0.5ppb and the highest level found was 1.34ppb.

A transcript for the video recording of the Marketing Masterclass on Restaurants Responding to Covid-19. This event was recorded in March 2021.