1993 - 1993 Centre for Environment, Fisheries & Aquaculture Science (Cefas) Irish Sea Plankton Survey - RV Cirolana 05/93
Plankton analysis results from a survey carried out in May-June 1993 in the Irish Sea to obtain estimates of zooplankton egg production in relation to both primary production and physical condition. A survey grid of 37 stations was sampled three times between 8-11 May, 16-18 May and 25-30 May. This data consists of the numbers of icthyoplankton and zooplankton, along with associated positional data and volumes filtered.
dataset
http://data.cefas.co.uk/#/View/2560/
function: order
CEFAS70949586-71f7-41aa-a4af-8f0c542e159c
http://www.cefas.co.uk/
eng
OGP
urn:ogc:def:crs:EPSG::4326
biota
revision
2011-03-25
publication
2008-06-01
publication
2008-06-01
-7
-2.5
55
51.75
revision
2010-05-18
1993-05-04
1993-06-02
publication
2020-01-28
notPlanned
Larvae were collected using a 2m diameter ring net and a 800 μm mesh. Dual Longhurst-Hardy Plankton Samplers deployments with coarse (270μm) and fine (20μm) mesh were also made at each station. For logistical reasons stations 30, 31 and 36 were not sampled on the second and third surveys. Sample collection: 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 laboratory for sorting and identification. Sample analysis: Analysis of all samples was carried out using Cefas standard methods and identification guides. Fish eggs and larvae were picked out from all samples by eye and, whenever practicable, the whole sample was sorted. When sub-sampling was necessary this was done 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 in 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) 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.
Public data (Crown Copyright) - Open Government Licence Terms and Conditions apply
Public data (Crown Copyright) - Open Government Licence Terms and Conditions apply
Data Manager
Centre for Environment, Fisheries & Aquaculture Science
Cefas Lowestoft Laboratory
Pakefield Road
Lowestoft
NR33 0HT
UK
+44 (0)1502 562244
originator
Data Manager
Centre for Environment, Fisheries & Aquaculture Science
Cefas Lowestoft Laboratory
Pakefield Road
Lowestoft
NR33 0HT
UK
+44 (0)1502 562244
custodian
Data Manager
Centre for Environment, Fisheries & Aquaculture Science
Cefas Lowestoft Laboratory
Pakefield Road
Lowestoft
NR33 0HT
UK
+44 (0)1502 562244
pointOfContact
2020-01-28T11:49:20