ea5cce71bf0b7c878642623503ddd102 English dataset Data Officer Northwestern Inshore Fisheries and Conservation Authority science@nw-ifca.gov.uk pointOfContact 2017-09-21 MEDIN Discovery metadata standard 2.3.8 urn:ogc:def:crs:EPSG::4978 1998 - Ongoing, North Western Inshore Fisheries and Conservation Authority (NWIFCA) Cockle Surveys 2013-09-27 publication NWIFCA_COC_ALL http://www.nw-ifca.gov.uk The NWIFCA conducts cockle surveys across its district in order to inform the management of this fishery. Data is collected on the density of cockles in an area, their status in relation to minimum landing size (20 mm) and age. Samples are also often taken for weighing and production of length frequency tables. This data can be used to estimate other parameters such as the mass of stock on the bed. In the past beds have been surveyed regularly (every year). However, the NWIFCA has moved toward a more adaptive survey strategy where beds are more often surveyed after reports of a possible commercial stock by local area officers. Northwestern Inshore Fisheries and Conservation Authority North Western IFCA dassh.enquiries@mba.ac.uk originator Northwestern Inshore Fisheries and Conservation Authority North Western IFCA dassh.enquiries@mba.ac.uk custodian irregular Delimited Documents Geographic Information System Marine Environmental Data and Information Network NDGO0005 Species distribution GEMET - INSPIRE themes, version 1.0 2008-01-06 revision Fauna abundance per unit area of the bed SeaDataNet P021 parameter discovery vocabulary 2009-11-16 revision Data is freely available for research or commercial use providing that the originators are acknowledged in any publications produced. A charge may be applied to cover costs of compiling and sending data. otherRestrictions No restrictions to public access 250 English biota Charting Progress 2 Sea Areas 2009-06-18 creation Irish Sea ICES Rectangles 2009-05-01 creation 35E6 ICES Rectangles 2009-05-01 creation 36E6 ICES Rectangles 2009-05-01 creation 37E6 ICES Rectangles 2009-05-01 creation 38E6 ICES Rectangles 2009-05-01 creation 39E6 ICES Rectangles 2009-05-01 creation 37E7 International Hydrographic Bureau, Limits of Oceans and Seas 1954-01-01 creation Irish Sea and St. George's Channel SeaDataNet vertical extent keywords 2010-01-01 revision benthic boundary layer SeaDataNet vertical extent keywords 2010-01-01 revision soil and sediment SeaDataNet vertical extent keywords 2010-01-01 revision troposphere ICES Statistical Areas 2014-05-16 creation VIIa -3.7354 -2.7356 53.3046 55.0091 1998-01-01 2017-09-21 Northwestern Inshore Fisheries and Conservation Authority North Western IFCA dassh.enquiries@mba.ac.uk distributor dataset Beds are surveyed using a series of survey points in a grid pattern, loaded onto GPS. This grid has a size of 50 to 500 m dependent on the size of bed and requirement for resolution. However, 250 m is the most common size. At each survey point a quadrat is placed onto the bed and cockles within this quadrat recorded. Two sizes of quadrat are used depending on the number and size of cockles present. A 0.5 m quadrat is used for less dense areas of large cockles. A jumbo is first used to bring cockles to the surface. A 0.1 m box quadrat is used for areas with dense spat settlements. Here the sediment within the quadrat is passed through a sieve. The number of cockles within a quadrat is recorded along with their age (determined from growth rings) and size (oversize, undersize, spat). Oversize (or size) cockles are those that do not pass through an opening 20 mm square. When there is a large number of spat an estimate is made as to their total number. Samples of cockles found in quadrats are taken for analysis in the lab. These are measured using a digital calliper to the nearest .5 mm and a wet weight taken. Available outputs from these surveys vary. These include raw data, amalgamated data, GIS data, thematic maps and reports.