CEFAS3ad64697-1c4f-471d-8266-b3b891f87c22 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 2023-10-31T12:47:25 EPSG Geodetic Parameter Registry 2022-01-07 revision WGS 84 North Sea Plankton Survey - RV Clione 09/1987 2016-03-09 publication 2023-10-31 revision 2016-03-07 creation CEFAS3786 https://data.cefas.co.uk A series of five surveys were carried out between May and September of 1987 in the North Sea off the north-east coast of England to undertake stock assessment by the egg production method. The species targeted were *Nephrops norvegicus* (Norway lobster) and *Homarus gammarus *(European lobster) with plankton samples being collected at each site on a planned survey grid. The data described here consists of the numbers of eggs and larvae, along with associated positional and ancillary data and volumes filtered. 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 notPlanned Microzooplankton Phytoplankton Zooplankton SeaDataNet P03 parameter discovery vocabulary 2011-03-25 revision Plankton Advice Analysis Management Monitoring 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 Public data - no limitations to reuse 1000 English biota -2.00 1.00 54.25 56.50 1987-06-25 1987-07-03 Delimited Geographic Information System Unknown https://data.cefas.co.uk/view/3786 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: CSV, ESRI Shapefile. The data can also be accessed via the WFS and WMS protocols. 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 Gear used for these cruises were: 76cm high speed tow net (HSTN) with a 40cm diameter nose cone, MIK net and neuston net, Sampler deployment:The HSTN sampler was deployed in a double oblique tow from the surface to within 2 m of the seabed. Veering and hauling speeds were manually adjusted to ensure that each depth band was sampled equally. At shallow stations, multiple double oblique dives were necessary to enable a sufficient volume of water to be filtered. A minimum sampler deployment time of 15 minutes was aimed for. On recovery, the net was carefully washed down and the sample collected from the end bag. Each sample was then fixed using buffered formaldehyde solution and transported to the participating laboratories for sorting and identification.Sample analysis:Fish eggs and larvae were picked out from all samples by eye and, whenever practicable, the whole sample was sorted. However sub-sampling was at times necessary. Sub-sampling was carried out using a Folsom splitter. Fish larvae were readily identified unless they had been badly damaged during collection or were prematurely hatched. For some groups such as the sandeels (Ammodytidae) and the group of Gadidae commonly called rocklings, individuals were not identified to the species level. Fish eggs were initially split into three groups on the basis of the presence or absence of oil globules. Those containing either a single or many oil globules could usually be identified to the species level. Eggs with no oil globules were more difficult to identify. Some of these species such as cod (*Gadus morhua*), sprat (*Sprattus sprattus*), long rough dab (*Hippoglossoides platessoides*), dragonet ( *Callionymus* spp.) and plaice (*Pleuronectes platessa*) were identified because of their size or unique features. Unidentified eggs in this group were recorded as egg diameters.Data storage:The raw data were stored on an Access database. The various data files were stored on the database in a series of tables linked by having the content of certain fields in common. All routine calculations, calibration changes and conversions were carried out on the database. The data tables (but not queries etc.) have now been extracted into text files. Plankton data are normally expressed as either number of organisms per m3 or per m2. The number per m3 is obtained by dividing the numbers per sample by the volume filtered, calculated from the sampler flowmeters. Number per m2 is obtained by multiplying the number per m3 by the mean sampled depth during a deployment. MEDIN 3.1.1