4f4c4942-4343-5764-6473-313130303639 English NRW_DS114501 Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en 2026-03-03T16:13:17.876Z NRW 1.0 wel Latitude and Longitude (EPSG::4326) Assessment of the Impact of Hydraulic Cockle Dredging on the Macroinvertebrate Faunas of Traeth Lafan (1993-1994) Assessment of the Impact of Hydraulic Cockle Dredging on the Macroinvertebrate Faunas of Traeth Lafan (1993-1994) Asesiad o effaith cribinio hydrolig am gocos ar ffawna macroinfertebratau Traeth Lafan (1993-1994) 1993-94 CCW Traeth Lafan hydraulic dredging impact survey JNCCMNCR40000693 1995-03-31 NRW_DS110069 This dataset contains the results of a macroinvertebrate and sediment survey conducted post hydraulic cockle dredging around Traeth Lafan, North Wales. The purpose of this data collection was to study the effects of hydraulic suction dredging on benthic invertebrate macrofaunas, substrate conformation and sediment composition on Traeth Lafan. The survey was located at Traeth Lafan, the northern entrance to the Menai Strait (Menai Strait and Colwyn Bay Special Area of Conservation (SAC)). A survey of the macroinvertebrates and sediments of Traeth Lafan, North Wales, was undertaken following extensive hydraulic cockle dredging in autumn 1993. The survey covered the site allocated for dredging and part of the hand gathering area, which was used as 'control', against which changes on the dredged ground could be compared. A follow up survey, using the same sampling grid and rationale, was carried out twelve months later, in November 1994, to ascertain the recovery state of the area after a full season's recruitment. This dataset contains the results of a macroinvertebrate and sediment survey conducted post hydraulic cockle dredging around Traeth Lafan, North Wales. The purpose of this data collection was to study the effects of hydraulic suction dredging on benthic invertebrate macrofaunas, substrate conformation and sediment composition on Traeth Lafan. The survey was located at Traeth Lafan, the northern entrance to the Menai Strait (Menai Strait and Colwyn Bay Special Area of Conservation (SAC)). A survey of the macroinvertebrates and sediments of Traeth Lafan, North Wales, was undertaken following extensive hydraulic cockle dredging in autumn 1993. The survey covered the site allocated for dredging and part of the hand gathering area, which was used as 'control', against which changes on the dredged ground could be compared. A follow up survey, using the same sampling grid and rationale, was carried out twelve months later, in November 1994, to ascertain the recovery state of the area after a full season's recruitment. Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Countryside Council for Wales (CCW) Countryside Council for Wales, Maes y Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW enquiries@naturalresourceswales.gov.uk http://naturalresourceswales.gov.uk/splash?orig=/ North Western And North Wales Sea Fisheries Committee = Pwllgor Pysgodfeydd Mor Gogledd Orllewin Lloegr a Gogledd Cymru 1 Preston Street, Carnforth, Lancashire, LA5 9BY, England office@nwnwsfc.org http://www.nwnwsfc.org/ Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en Species distribution GEMET - INSPIRE themes, version 1.0 2008-06-01 geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme cockle dredging (hydraulic dredging) macroinvertebrates benthic species Lafan sands (Lavan sands)(Traeth Lafan) marine and freshwater inventory marine sediments (coastal sediments) (intertidal sediments) (subtidal sediments) Menai Strait NRW Thesaurus 2025-01-08 geonetwork.thesaurus.local.theme.converted_nrw-keywords Shellfish abundance and biomass in water bodies Sedimentary structure Fishery characterisation Sediment grain size parameters SeaDataNet Parameter Discovery Vocabulary 2024-06-19 geonetwork.thesaurus.external.theme.rdf+xml There are no access restrictions to this data. CCW may release, publish or disseminate it freely. no limitations © CCGC/CCW 1995. There are no use restrictions on this data. Recipients may re-use, reproduce, disseminate this data free of charge in any format or medium, provided they do so accurately, acknowledging both the source and CCW's copyright, and do not use it in a misleading context. It is the recipient's responsibility to ensure the data is fit for the intended purpose, that dissemination or publishing does not result in duplication, and that it is fairly interpreted. Advice on interpretation should be sought where required. To avoid re-using old data, users should periodically obtain the latest version from the original source. 4000 English biota SeaVoX Vertical Co-ordinate Coverages 2021-01-06 benthic boundary layer SIR YNYS MON - ISLE OF ANGLESEY Wales (WLS) -4.07804031 -4.00676046 53.24506231 53.25916295 1993-12-12 1994-12-29 There is an associated report to accompany this dataset: P.Allen., CCW. 1995 An assessment of the impact of hydraulic cockle dredging on the macroinvertebrate faunas of Traeth Lafan, North Wales CCW Science Report No. 64. Bangor. An assessment of the impact of hydraulic cockle dredging on the macroinvertebrate faunas of Traeth Lafan, North Wales Documents [A] Report is held as a .pdf file, data is held as .SAM and .WPS files. [B] Floppy disk 1 398KB (WPS files) [C] Floppy disk 2 575KB (SAM files) [D] Report- scanned copy in PDF format [E] Survey data in Marine Recorder (JNCCMNCR40000693) 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 This dataset has not been assessed for conformance to the referenced INSPIRE regulation. false The survey consisted of a widespread survey using a grid of single sample stations and an intensive survey of four stations with replicate sampling, deployed across the dredged area. Both the single survey grid and one replicate station covered an area of 'control' ground allocated to hand gathering. 0.01m-2 x 0.2 sediment cores were collected at each sampling station and surface evidence of deeper burrowing animals was recorded. A sample was taken of the surface sediment for granulometric analysis, substrate shear strength was measured and the presence of other physical features recorded. Samples were sent to the laboratory for analysis. There is a high confidence in this data, however no spatial reference were provided with data for statistical analysis. It is assumed for the purpose of the metadata that samples were collected using Latitude and Logitude (WGS84). The post disturbance ecological survey was carried out on 12th December 2003 and 8th January 2004 with the follow up survey undertaken on the 28th and 29th of December 1994. Confidence in this dataset is high, however no spatial reference were provided with data for statistical analysis. It is assumed for the purpose of the metadata that samples were collected using Latitude and Logitude (WGS84). The survey consisted of a widespread survey using a grid of single sample stations and an intensive survey of four stations with replicate sampling, deployed across the dredged area. Both the single survey grid and one replicate station covered an area of 'control' ground allocated to hand gathering. 0.01m-2 x 0.2 sediment cores were collected at each sampling station and surface evidence of deeper burrowing animals was recorded. A sample was taken of the surface sediment for granulometric analysis, substrate shear strength was measured and the presence of other physical features recorded. Samples were sent to the laboratory for analysis. There is a high confidence in this data, however no spatial reference were provided with data for statistical analysis. It is assumed for the purpose of the metadata that samples were collected using Latitude and Logitude (WGS84). The post disturbance ecological survey was carried out on 12th December 2003 and 8th January 2004 with the follow up survey undertaken on the 28th and 29th of December 1994. Confidence in this dataset is high, however no spatial reference were provided with data for statistical analysis. It is assumed for the purpose of the metadata that samples were collected using Latitude and Logitude (WGS84).