4f4c4942-4343-5764-6473-313031373235 English Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en 2024-12-09T12:37:18.762Z NRW 1.0 wel British National Grid (EPSG::27700) Age and Growth Analysis of Native Oyster Beds (Ostrea edulis) in Wales Age and Growth Analysis of Native Oyster Beds (Ostrea edulis) in Wales Dadansoddiad o oed a thwf gwelyau wystrys (Ostrea edulis) yng Nghymru 2003-04-30 NRW_DS101725 The native flat oyster Ostrea edulis is a UK and Welsh Biodiversity Action Plan (BAP) species, for which a UK action plan exists. Native oysters have a long history of over-exploitation in Wales and elsewhere in the UK. Harvested beds in Wales used to be present off Porthcawl, Swansea Bay and Mumbles, Milford Haven, Cardigan, Pwllheli and the Menai Strait. All of these fisheries declined during the early 1900's due to intense exploitation, possibly combined with disease and poor recruitment. Significant oyster beds are now restricted to Milford Haven, Swansea Bay and Porthcawl, although at a much reduced scale. The remaining oyster populations in Wales are under threat through increased fishery effort in the existing oyster fishery and from diversification of fishing activities in the fisheries. Dredging activity used in harvesting sublittoral oysters causes physical damage to the seabed and associated marine biodiversity. Oyster beds in Milford Haven occur in the Pembrokeshire Marine Special Area of Conservation (SAC) and form part of the features for which the SAC is designated. The present work reports on the morphometric characteristics, the age structure, growth and settlement of Ostrea edulis populations from seven sites in Milford Haven in Pembrokeshire (Wales, UK). Information gained from the project will contribute to an ecological understanding of native oyster beds and provide management advice for the remaining native oyster beds in Wales. The native flat oyster Ostrea edulis is a UK and Welsh Biodiversity Action Plan (BAP) species, for which a UK action plan exists. Native oysters have a long history of over-exploitation in Wales and elsewhere in the UK. Harvested beds in Wales used to be present off Porthcawl, Swansea Bay and Mumbles, Milford Haven, Cardigan, Pwllheli and the Menai Strait. All of these fisheries declined during the early 1900's due to intense exploitation, possibly combined with disease and poor recruitment. Significant oyster beds are now restricted to Milford Haven, Swansea Bay and Porthcawl, although at a much reduced scale. The remaining oyster populations in Wales are under threat through increased fishery effort in the existing oyster fishery and from diversification of fishing activities in the fisheries. Dredging activity used in harvesting sublittoral oysters causes physical damage to the seabed and associated marine biodiversity. Oyster beds in Milford Haven occur in the Pembrokeshire Marine Special Area of Conservation (SAC) and form part of the features for which the SAC is designated. The present work reports on the morphometric characteristics, the age structure, growth and settlement of Ostrea edulis populations from seven sites in Milford Haven in Pembrokeshire (Wales, UK). Information gained from the project will contribute to an ecological understanding of native oyster beds and provide management advice for the remaining native oyster beds in Wales. 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 University of Wales, Bangor. School of Ocean Sciences Bangor, Gwynedd, LL57 2DG oss011@bangor.ac.uk http://www.bangor.ac.uk Natural Resources Wales (NRW) Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd, LL57 2DW, Wales enquiries@naturalresourceswales.gov.uk http://naturalresources.wales/?lang=en sd">Species distribution Species distribution GEMET - INSPIRE themes, version 1.0 GEMET - INSPIRE themes, version 1.0 2008-06-01 geonetwork.thesaurus.external.theme.httpinspireeceuropaeutheme-theme native oyster ostrea edulis NRW Thesaurus NRW Thesaurus 2023-12-31 geonetwork.thesaurus.local.theme.converted_nrw-keywords Shellfish morphology, age and physiology Shellfish abundance and biomass in water bodies SeaDataNet Parameter Discovery Vocabulary SeaDataNet Parameter Discovery Vocabulary 2021-01-06 geonetwork.thesaurus.external.theme.rdf+xml Part of this dataset is sensitive and restricted. The sensitive data is as follows; Ostrea Edulis locations and habitat locations. Sensitive data must be kept confidential; general release is not permitted due to risk of harm to the environment or third parties. Sensitive data may only be released under an appropriate NRW Licence. Requests should be referred to NRW's Access to Information Officer. Data may be released freely if the sensitive records are removed in advance, or shown only at a coarser scale. no limitations © CNC/NRW 2003. Recipients may only re-use sensitive data in strict confidence under the terms of an appropriate NRW Licence. No publication or dissemination is permitted, except if sensitive records are removed in advance, or shown only at a coarser scale. English biota SeaVoX Vertical Co-ordinate Coverages SeaVoX Vertical Co-ordinate Coverages 2021-01-06 benthic boundary layer Wales (WLS) -5.00416402 -4.85378338 51.66541605 51.75529622 2002-09-01 2002-09-30 Age and growth analysis of native oyster beds (ostrea edulis) in Wales. CONFIDENTIAL Documents [A] Images in JPEG, [B] PDF and Word Documents. 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 false Samples of Ostrea edulis were collected from eight sites in Milford Haven in Pembrokeshire, South Wales (UK) during September 2002. No oysters were found during the survey in Swansea and Porthcawl, South Wales (U.K) (Thomas, 2003). The sites 1a, 1b, 2, 4 and 6 were located in the middle section of the Milford Haven waterway from a non-commercially exploited oyster area, whereas sites 7, 9 and 10 were further upstream and are from a commercially exploited oyster area. Laboratory examination of Oysters recorded shell length (L), width (W) and height (H) and dry weight of flesh calculated in order to perform morphometric analysis. Samples of Ostrea edulis were collected from eight sites in Milford Haven in Pembrokeshire, South Wales (UK) during September 2002. No oysters were found during the survey in Swansea and Porthcawl, South Wales (U.K) (Thomas, 2003). The sites 1a, 1b, 2, 4 and 6 were located in the middle section of the Milford Haven waterway from a non-commercially exploited oyster area, whereas sites 7, 9 and 10 were further upstream and are from a commercially exploited oyster area. Laboratory examination of Oysters recorded shell length (L), width (W) and height (H) and dry weight of flesh calculated in order to perform morphometric analysis.