Marine_Scotland_FishDAC_12537 eng dataset Scottish Government (Marine Scotland) +44 (0)300 244 4000 marinescotland@gov.scot pointOfContact 2025-02-25 MEDIN Discovery Metadata Version 2.3.7 urn:ogc:def:crs:EPSG::4326 OGP FishDAC - Scallop Survey (Scotland) 2025 - Shetland 2025-02-25 publication Marine_Scotland_FishDAC_12537 Objectives 1. To carry out a survey of King scallop stocks around the Shetland Islands. 2. To age, measure and assess shell damage on all King scallops caught. 3. To collect information on by-catch of other commercial fish and shellfish species. 4. To identify, quantify and damage assess starfish species in all dredge tows. 5. To collect whole scallops for heavy metal testing as part of the OSPAR assessment of hazardous substances in the marine environment. 6. To record and retain marine litter obtained during the dredging process (monitoring for Marine Strategy Framework Directive). 7. To collect scallop shells to form part of a reference and training set for Scotland. 8. To collect King scallops showing any shell deformities. 9. Accommodate a scientist from the University of the Highlands and Islands. Scottish Government (Marine Scotland) +44 (0)300 244 4000 Mailpoint 11, Area 1B South, Victoria Quay Edinburgh EH6 6QQ United Kingdom marinescotland@gov.scot pointOfContact Scottish Government (Marine Scotland) +44 (0)300 244 4000 Mailpoint 11, Area 1B South, Victoria Quay Edinburgh EH6 6QQ United Kingdom marinescotland@gov.scot custodian Scottish Government (Marine Scotland) +44 (0)300 244 4000 Mailpoint 11, Area 1B South, Victoria Quay Edinburgh EH6 6QQ United Kingdom marinescotland@gov.scot distributor Marine Scotland Science 375 Victoria Road Aberdeen AB11 9DB United Kingdom marinescotland@gov.scot originator unknown Marine Environmental Data and Information Network Fish and shellfish catch statistics Shellfish abundance and biomass in water bodies SeaDataNet Parameter Discovery Vocabulary 2018-12-12 revision Habitats and biotopes Species distribution GEMET - INSPIRE themes, version 1.0 2009-07-31 revision Introduction of energy does not adversely affect the marine environment Marine Strategy Framework Directive descriptors 2017-02-25 revision Contains information from the Scottish Government (Marine Scotland) licensed under the Open Government Licence otherRestrictions no limitations to public access 200.00 eng biota oceans -2 0 59.5 61 ICES Rectangles 1910-01-01 creation 48E8 ICES Rectangles 1910-01-01 creation 49E8 ICES Rectangles 1910-01-01 creation 50E8 ICES Rectangles 1910-01-01 creation 49E9 ICES Rectangles 1910-01-01 creation 50E9 SeaDataNet vertical extent keywords 2010-01-01 revision The water column that is significantly influenced by the seabed, which is broader in deep ocean than in shelf seas. Guideline approximation is bottom 10m of oceans and bottom 5% of shelf (<200m) seas. 2025-01-26 2025-02-10 http://www.scotland.gov.uk/Topics/marine/marine-environment/species/fish/shellfish/scallop http://www.scotland.gov.uk/Publications/2013/09/6505/24 http://www.scotland.gov.uk/Publications/2013/01/9421 NA offlineAccess NA offlineAccess dataset Dredge surveys of the scallop grounds around Scotland have been carried out by Marine Directorate (MD) since the mid-1990’s (partial surveys of the west coast began in the late 1980’s). There are currently four surveys each year which collectively cover the major scallop fishing grounds to the west of Scotland (including Clyde), the North Sea (Scottish coast) and around Shetland. MD has carried out 28 surveys around Shetland with the first one being carried out in 1995. Thereafter, surveys were done on an annual basis with 1997, 2014 and 2015 the only years where they did not take place due to bad weather. Three vessels have been used to conduct the surveys, Cornucopia in 1995 and 1996, Clupea from 1998 to 2008 and Marine Research Vessel (MRV) Alba na Mara from 2009 to the present day. The main aim of the survey is to collect standardised catch rate data for King scallops for use in stock assessment. Method The surveys have a fixed station design. The station locations were originally determined with reference to British Geological Survey charts to locate sediments suitable for scallops and also using knowledge of the fishing grounds contributed by skippers fishing at the time when the surveys first took place. There are around 90 fixed stations which have been historically fished around Shetland, however, these are not all carried out every year as the survey can be affected by time constraints, bad weather, aquaculture activity and closed areas. The west of Shetland is not covered on a regular basis due to the prevailing westerly winds limiting access by a small research vessel. An average Shetland survey of this duration with favourable weather conditions would aim to fish 40 to 50 of the stations. Two dredge arrays were fished (one either side of the research vessel, Alba na mara). One array consisted of standard commercial spring-loaded Newhaven type dredges (75 cm wide, nine tooth bar, with 80 mm internal diameter belly rings, Type A, referred to as S9 fished from the starboard side). The second array consisted of smaller configuration sampling dredges with 11 teeth and smaller diameter belly rings (Type B), more similar to commercial gear for queen scallops (Aequipecten opercularis) (75 cm wide, 11 tooth bar, with 60 mm internal diameter belly rings, referred as P11 fished from the port side). This side of gear is configured to catch smaller scallops compared to the commercial dredges. At each station the dredges were towed at a speed of about 2.5 knots for approximately 30 minutes with both sides of dredges on the seabed. All king scallops caught were aged and measured (length to the 0.5 cm below) in accordance with the MD Scallop ageing standard operating procedure and damage assessed in accordance with the damage index¬¬1. The total width of dredges used in the survey has changed over the survey time series. Catch rate data are, therefore, further standardised and expressed as numbers caught per hour per metre dredge width (N hr-1 m-1). Bycatch, including starfish, were collected, identified, measured, sexed and damage assessed, with the same damage index referenced for the scallops, where appropriate.