Identification

Title

2015 - 2015 Centre for Environment, Fisheries & Aquaculture Science (Cefas) Developing the selective Net Grid trawl in the NE Nephrops trawl fishery 2015/16 - Fisheries Science Partnership

Alternative title(s)

FSP Developing the selective Net Grid trawl in the NE Nephrops trawl fishery

Abstract

This work was carried out as part of the Fisheries Science Partnership (FSP) programme. The trawler Luc SN 36 was chartered for 14 days between October and December 2015 to undertake trials in the *Nephrops* fishery off the North east coast of England. The specific objective was to modify the incline panel and the escape hole of the selective Net Grid trawl design to enable retention of marketable fish while still minimising catches of unwanted fish. The Net Grid is made of a 4-panel box section inserted into a standard two-panel trawl into which an inclined sheet of netting is laced. On top of the box section in front of netting grid is a fish escape hole. The netting grid acts as a physical barrier and guides fish out of the escape-hole while *Nephrops* pass through the netting to the cod end.

Resource type

dataset

Resource locator

http://data.cefas.co.uk/#/View/18684/

function: order

Unique resource identifier

code

CEFASd91b43a8-f8cc-415a-92eb-effdd16456e4

codeSpace

http://www.cefas.co.uk/

Dataset language

eng

Spatial reference system

authority code

OGP

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

originating controlled vocabulary

title

reference date

date type

revision

effective date

2011-03-25

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2008-06-01

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

publication

effective date

2008-06-01

Geographic location

West bounding longitude

-2

East bounding longitude

-0.5

North bounding latitude

55.25

South bounding latitude

54.5

Extent

Extent group

authority code

title

reference date

date type

revision

effective date

2010-05-18

code identifying the extent

Temporal reference

Temporal extent

Begin position

2015-10-01T00:00:00.000Z

End position

2015-12-31T00:00:00.000Z

Dataset reference date

date type

publication

effective date

2017-08-23

Frequency of update

notPlanned

Quality and validity

Lineage

Prior to this project, Cefas in collaboration with several skippers from the NE English *Nephrops* fishery, had shown it was possible to catch *Nephrops* with very low cod catches using the Net Grid trawl (the initial motivation for the design), however, this also meant large reductions in the catches of other marketable fish. Therefore, while the Net Grid was efficient at minimising fish catches while retaining *Nephrops* , it was considered a rather blunt tool, whereby skippers could either catch fish (including unwanted fish) and *Nephrops* with a conventional trawl or only *Nephrops* with the Net Grid trawl. The idea came from the industry to further develop the Net Grid design so that it could retain marketable fish while still avoiding unwanted catches. The modifications to the Net Grid were to the escape hole at the top of the inclined netting grid in order to retain large marketable fish, and to the length of the inclined netting grid so that there was space at the bottom of the grid under which marketable fish could pass. Two modifications were tested, a simple cover of the escape hole with T90 120mm netting and the insertion of a larger section of T90 120mm in the top of the trawl above the netting grid including the area of the escape hole. Both designs included removing 8 meshes from the bottom edge of the inclined netting grid. To test the two designs, it was necessary to observe the fish that escaped through the T90 sections and compare with the fish that were retained in the cod end of the trawl. This was done by designing a cover over the T90 escape sections which terminated in a secondary top (cover) cod end. The catches retained in the two cod ends demonstrated which fish had entered the trawl and escaped through the T90 sections compared with those which were retained in the trawl and would have been caught if the trawl was applied commercially.

Conformity

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Public data (Crown Copyright) - Open Government Licence Terms and Conditions apply

Constraint set

Limitations on public access

Public data (Crown Copyright) - Open Government Licence Terms and Conditions apply

Responsible organisations

Responsible party

contact position

Data Manager

organisation name

Centre for Environment, Fisheries & Aquaculture Science

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

telephone number

+44 (0)1502 562244

email address

data.manager@cefas.co.uk

responsible party role

originator

Responsible party

contact position

Data Manager

organisation name

Centre for Environment, Fisheries & Aquaculture Science

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

telephone number

+44 (0)1502 562244

email address

data.manager@cefas.co.uk

responsible party role

custodian

Metadata on metadata

Metadata point of contact

contact position

Data Manager

organisation name

Centre for Environment, Fisheries & Aquaculture Science

full postal address

Cefas Lowestoft Laboratory

Pakefield Road

Lowestoft

NR33 0HT

UK

telephone number

+44 (0)1502 562244

email address

data.manager@cefas.co.uk

responsible party role

pointOfContact

Metadata date

2017-08-23T12:06:27

Metadata language