CEFAS6572f29a-8054-4226-8e27-29b966eb9108 English dataset Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS) Cefas Lowestoft Laboratory Pakefield Road Lowestoft Suffolk NR33 0HT UK data.manager@cefas.co.uk pointOfContact 2020-01-03T12:21:53 EPSG Geodetic Parameter Registry 2022-01-07 revision WGS 84 CCTV development on Western Irish Sea nephrops vessels 2009/10 - Fisheries Science Partnership FSP CCTV development on Western Irish Sea nephrops vessels 2016-11-14 publication 2020-01-03 revision 2013-10-23 creation CEFAS2944 https://data.cefas.co.uk To develop a cost effective method in monitoring the amount of cod by-catch within the Irish Sea *Nephrops* fishery by using CCTV. Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS) Cefas Lowestoft Laboratory Pakefield Road Lowestoft Suffolk NR33 0HT UK data.manager@cefas.co.uk originator Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS) Cefas Lowestoft Laboratory Pakefield Road Lowestoft Suffolk NR33 0HT UK data.manager@cefas.co.uk custodian Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS) Cefas Lowestoft Laboratory Pakefield Road Lowestoft Suffolk NR33 0HT UK data.manager@cefas.co.uk distributor Centre for Environment, Fisheries and Aquaculture Science, Lowestoft Laboratory (CEFAS) data.manager@cefas.co.uk owner Department for Environment, Food and Rural Affairs (DEFRA) defra.helpline@defra.gov.uk owner notPlanned Biota abundance, biomass and diversity SeaDataNet P03 parameter discovery vocabulary 2011-03-25 revision Crustacean GEMET, version 1.0 2008-06-01 publication Species distribution GEMET - INSPIRE themes, version 1.0 2008-06-01 publication Water column SeaVoX Vertical Co-ordinate Coverages 2010-05-18 revision Marine Environmental Data and Information Network MEDIN metadata record availability 2012-01-11 publication data.gov.uk MEDIN metadata record availability 2012-01-11 publication otherRestrictions noLimitations otherRestrictions Adherance to the Cefas Data access policy required. Terms and conditions of OGL – Open Government Licence apply. `http://www.nationalarchives.gov.uk/doc/open-government-licence/`_ .. _`http://www.nationalarchives.gov.uk/doc/open-government-licence/`: http://www.nationalarchives.gov.uk/doc/open-government-licence/ English biota -7.00 -2.00 52.50 54.75 2009-09-09 2009-09-22 Binary Unknown https://data.cefas.co.uk/view/2944 Cefas Data Portal download The Cefas Data Portal contains metadata records and data sets available to download and connect to in support of our commitment to open science. Data is available in the following formats: Binary download. dataset INSPIRE Data Specification on Species Distribution – Technical Guidelines 2013-12-10 publication false See the referenced specification Commission Regulation (EU) No 1089/2010 of 23 November 2010 implementing Directive 2007/2/EC of the European Parliament and of the Council as regards interoperability of spatial data sets and services 2010-12-08 publication true See the referenced specification Methods The fishing vessel “Supreme” (CN180) was selected to participate in the trials through an open tender process. It is a 16.16 m (LOA) wooden-hulled prawn trawler powered by a 229 bhp Gardner engine. The fishing gear used during the trial consisted of a 22 fathom dual-purpose single-rig net with 70 mm codend, fished off 30 fathom bridles with 8 fathom rubber legs. The trawl doors were 6 foot Dunbar design. Survey design The first part of the trial consisted of a period of three sea-days, during which cameras were sited in the most appropriate positions available to monitor catches. It also allowed the observer the opportunity to become familiar with the recording equipment and the vessels catch-handling procedure. During this part of the trial, there was a requirement of the vessel’s crew to record details of total catch weight, along with numbers and estimated weights for any cod caught, whether retained or discarded. This information will be compared with data extracted from the video footage to evaluate the potential for video footage to be used to validate additional records completed by fishers. Based on the findings from Part 1 of the survey, the second leg (Part 2) trial was modified so that the only requirement for the crew of the vessel was that all cod be placed in baskets and/or processed (i.e. no cod was to be discarded directly from the pound). This was done to test how effective the CCTV equipment and footage would be at assessing the cod catch independent of any modified crew behaviour. Sorting and processing the catch The aim of the project was to evaluate whether or not the CCTV equipment was capable of accurately assessing the percentage of cod in relation to the total catch, independently of any modified catch handling. As such, the only condition placed on the crew was that no cod was to be discarded directly from the pound (as is common practice in many fisheries where fishers believe that returning the fish to the sea in a timely manner will increase the chances of the fish surviving). The observer was also given the opportunity to sort through baskets to identify and measure cod where present before rebasketing and processing by the crew as normal. CCTV monitoring equipment Several camera positions were trialled during the trips, as were a variety of lenses (ranging from 2.1 to 12 mm) on the cameras. The most suitable locations for cameras were determined through trial and error through Part 1 and the early stages of Part 2. Catch Assessment In order to fulfil the requirements of the project, an estimate of total catch per fishing event, along with estimates (by length) for all cod (Gadus morhua) were required. During the first few days of Part 1 of the trial, all baskets were weighed, and the values averaged to provide a nominal average basket weight of 19.68 kg. This value was used for the remainder of the Part 1 trials, along with all hauls conducted during part 2 trials. As mentioned above, Part 1 trials involved a modified catch-handling regime, whereby all cod caught were to be passed over a fixed measuring board mounted on the sorting table prior to further processing and/or discarding. Actual basket counts, along with length measurements and the fate of all cod caught were recorded for all tows conducted during the trip. Video-footage was subsequently analysed on land (Part 1 trials by 1 person, Part 2 by 2 persons). The data collected included an estimate of total bulk (basket count + any observed discarding direct from the pound), presence or absence of cod, the fate of the cod observed, and an estimate of individual fish lengths. The length data were subsequently converted to a weight estimate by means of the conversion factor W = aLb, where W is the fish weight (g), a = 0.010752, L is fish length (cm), and b = 3 (derived from data collected on AFBI trawl surveys of the Irish Sea up to2000). Where discrepancies in video analysis were identified (for Part 2 trials only), footage was reviewed again by both analysts in an attempt to resolve them. Summary Irish Sea CCTV camera trials were conducted during September 2009, in the Northern Irish Nephrops fishery out of Ardglass. An array of 3 standard definition cameras and associated hardware were installed on the Nephrops trawler MFV Supreme, fishing a dual-purpose 22 fathom single-rig net with 70mm cod end, co-owned by Leo McGirr and Simon Wills (skippered by Leo McGirr). The aim of the project was to evaluate how effective CCTV technology was in assessing the cod bycatch as a percentage of the total catch in this fishery. In particular, the intention was to find a way of enhancing the monitoring of a sector of the fleet potentially excluded from cod recovery measures by virtue of that sector accounting for <1.5% of cod in the total catch. Results from the first series of trials (9–11 September) showed that, where crew catch-handling was modified, accurate assessments of cod live weights and hence percentage cod in the total catch could be made by video analysis in a cost-effective manner. Conversely, the initial trials also highlighted problems with species recognition of fish <30 cm total length. A second series of trials conducted from 23 to 27 September focused on whether or not the CCTV equipment could accurately assess the cod bycatch independent of any modified catch handling. Results indicated that video analysis failed to identify 81% of cod catches (by number). This was due to the small size of the cod being caught (mainly 12–20 cm), the presence of morphologically similar species (whiting, blue whiting, poor cod, haddock and Norway pout) in the catches, and the manual sorting and discarding procedures used on board. The findings show that CCTV technology is perhaps not the most effective tool for monitoring small-mesh fisheries, such as the trawl fishery for Nephrops. The results do, however, support further investigation of the utility of CCTV technology in fisheries where larger fish are encountered (e.g. otter trawls using 120mm+ cod ends) or more selective fisheries (such as gillnetting or longlining), where gear (and by default, fish) retrieval is at a steady rate. MEDIN 3.1.1