Identification

Title

2009-2012 Eastern Inshore Fisheries and Conservation Authority (Eastern IFCA) River Stour and Orwell clam surveys

Abstract

Between 2009 and 2012, Eastern IFCA (and its predeccesor, ESFJC) conducted stock assessment surveys of Manila clams (Vererupis philippinarum) along both the River Stour and River Orwell, Suffolk. The aim of the surveys was to monitor the presence of Manila Clams with the potential of identifying any potential commerical stocks that could be fished.

Resource type

dataset

Resource locator

http://www.eastern-ifca.gov.uk/

description: A link to the general host site

Unique resource identifier

code

EIFCASuffolkClams

codeSpace

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

urn:ogc:def:crs:EPSG::4326

Classification of spatial data and services

Topic category

biota

Keywords

Keyword set

keyword value

Keyword set

keyword value

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2008-01-06

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2009-11-16

Geographic location

West bounding longitude

1.1896

East bounding longitude

1.2196

North bounding latitude

51.9548

South bounding latitude

51.9425

Extent

Extent group

authority code

title

reference date

date type

creation

effective date

2009-06-18

code identifying the extent

Southern North Sea

Extent group

authority code

title

reference date

date type

revision

effective date

2010-01-01

code identifying the extent

infralittoral

Temporal reference

Temporal extent

Begin position

2015-04-07

End position

2015-04-07

Dataset reference date

date type

creation

effective date

2015-04-07

date type

revision

effective date

2015-04-07

Frequency of update

notPlanned

Quality and validity

Lineage

Between 2009 and 2012, samples of Manila clams (Vererupis philippinarum) were collected at regular intervals in the summer, on a predetermined grid deployed from Kent and Essex IFCA vessel, RV Tamesis over high water. Forty-four stations were surveyed along the northern bank of the River Orwell between the Orwell Bridge and Levington Creek. Seventy-four stations were surveyed in the Holbrook bay area of the River Stour. Sample stations were spaced approx. 250 meters apart on the grid. Two to three samples were collected from each station using a 0.1m square day grab then the samples were washed over 3 millimetres (mm) washing table and any clams found were retained. Samples of clams were measured to the nearest mm by length and width and individually weighted to the nearest 0.01 gram. A qualitative description of the sediment type at each station was noted. Manila Clam (V. philippinarum) distribution and density maps were created in MapInfo GIS. The biomass of the Manila clams in each river was calculated by multiplying the mean weight of the samples by the area covered. Length measurements and size distributions were recorded for comparison of data between survey years.

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Data is freely available for research or commercial use providing that the originators are acknowledged in any publications produced. Charts are not to be used for navigation.

Constraint set

Limitations on public access

There are no access restrictions.

Responsible organisations

Responsible party

contact position

MEO Data Lead

organisation name

Eastern Inshore Fisheries and Conservation Authority

email address

mail@eastern-ifca.gov.uk

responsible party role

originator

Responsible party

contact position

MEO Data Lead

organisation name

Eastern Inshore Fisheries and Conservation Authority

email address

mail@eastern-ifca.gov.uk

responsible party role

custodian

Metadata on metadata

Metadata point of contact

contact position

MEO Data Lead

organisation name

Eastern Inshore Fisheries and Conservation Authority

email address

mail@eastern-ifca.gov.uk

responsible party role

pointOfContact

Metadata date

2016-11-15

Metadata language