2010 to Present EIFCA (Eastern Inshore Fisheries and Conservation Authority) The Wash Intertidal Cockle Surveys
Intertidal cockle surveys are conducted annually in spring between the end of March and throughout April. Data is collected for stock assessments to inform fisheries management of the Wash Fishery Order 1992 regulated cockle fishery (Total Allowable Catch, which beds to open, spatial closures to protect juvenile stocks and to identify potential issues that might cause natural mortality to occur as a result of over-crowding). Data also forms part of the Habitats Regulation Assessment (HRA) process required to open a fishery under Regulation 61 of The Conservation of Habitats and Species Regulations 2010 (SI No. 2010/490), regarding The Wash and North Norfolk Coast Special Area of Conservation (Habitats Directive), The Wash Special Protected Area (Birds directive), the Wash Ramsar and SSSIs. Surveys are conducted on the intertidal sandbanks and mudflats of The Wash, which are broken down into 22 beds/survey areas. The survey incorporates approximately 1,250 sample stations that are arranged in a regular grid pattern with the same stations being used each year. Sampling is conducted either using a 0.1m2 Day grab over high water periods or by sampling on foot at low water using a 0.1m2 quadrat.
dataset
http://www.eastern-ifca.gov.uk/research-environment-plans-strategies-reports/
name: EIFCA publications
description: EIFCA reports and publications
http://www.eastern-ifca.gov.uk/
name: EIFCA Home
description: EIFCA website
EIFCA_WFO1992_cockle_surveys
eng
urn:ogc:def:crs:EPSG::4326
biota
revision
2008-01-06
revision
2009-11-16
creation
2015-04-07
0.0138
0.4547
53.0882
52.8093
creation
2009-06-18
Southern North Sea
creation
1954-01-01
North Sea
creation
2014-05-16
IVc
revision
2010-01-01
benthic boundary layer
2003-03-01
2018-10-26
publication
2010-10-01
revision
2017-05-31
annually
Each annual survey survey incorporates approximately 1,250 sample stations that are arranged in a regular grid pattern with the same stations being used each year. Sampling is conducted either using a 0.1m2 Day grab over high water periods or by sampling on foot at low water using a 0.1m2 quadrat. For each station the length and width of each cockle is measured to the nearest 1mm. The cockles are divided into two size groups (Gtr or equal 14mm width and less 14mm width), which are further sub-divided by age (Year-class). The number of cockles in each size-age group and the total weight of cockles in each group are recorded. Data is recorded directly into an Access database. These data are exported to MapInfo GIS for analysis, in which charts are hand-drawn to show the modelled distribution of the cockle stocks using Nearest Neighbour interpolation. These charts show cockle density distributions of 10-99/m2, 100-499/m2, 500-999/m2 and 1,000+/m2. Separate charts are drawn to show the distributions of Gtr and equal 14mm stocks, less 14mm stocks and Year-0 cohort stocks. For each bed/survey area the total biomass of these three groups is calculated, plus the mean density and mean biomass. Cockle size frequency charts are also produced for each survey area/bed.
No restriction to public access
No restriction to public access
Senior Research Officer
Eastern Inshore Fisheries and Conservation Authority
originator
Marine Science Officer
Eastern Inshore Fisheries and Conservation Authority
custodian
Marine Science Officer
Eastern Inshore Fisheries and Conservation Authority
pointOfContact
2018-10-26