Identification

Title

2007 Scottish Natural Heritage (SNH) Treshnish Isles rocky reefs site condition monitoring survey

Abstract

The purpose of benthic survey around the Treshnish Isles was to initiate site condition monitoring (SCM) of the littoral and sublittoral reef feature of the Isle of May SAC. The SCM survey was undertaken with the objectives to: establish a baseline biological data set that will facilitate the assessment of the favourable conditional status of the reefs in future; and to allow SNH to form judgement on the current condition of the reefs in light of existing SAC management measures. To fulfil these objectives an extensive drop-down video survey of the sublittoral reef habitats of the SAC at 86 sites to characterise the major reef biotopes and MNCR phase 2 surveys of reef biotopes along relocatable transects at 6 sites spanning both littoral and inshore sublittoral environments.

Resource type

dataset

Resource locator

Unique resource identifier

code

GB-SCT-SNH-ME-000113-MRSNH00800000003-TRESH

codeSpace

http://www.nature.scot

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

urn:ogc:def:crs:EPSG::27700

Additional information source

Moore, Edwards, Harries, Mair (2009) The establishment of site condition monitoring of the rocky reefs of the Treshnish Isles Special Area of Conservation.

Classification of spatial data and services

Topic category

biota

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

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

creation

effective date

2011-02-16

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

creation

effective date

2011-07-06

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

creation

effective date

2012-03-16

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

revision

effective date

2005-04-27

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

creation

effective date

2006-08-31

Keyword set

keyword value

originating controlled vocabulary

title

reference date

date type

creation

effective date

2017-05-12

Geographic location

West bounding longitude

-6.4660

East bounding longitude

-6.3448

North bounding latitude

56.5389

South bounding latitude

56.4626

Extent

Extent group

authority code

title

reference date

date type

creation

effective date

2009-06-18

code identifying the extent

Minches & Western Scotland

Extent group

authority code

title

reference date

date type

creation

effective date

2009-05-01

code identifying the extent

41E3

Extent group

authority code

title

reference date

date type

creation

effective date

2009-05-01

code identifying the extent

42E3

Extent group

authority code

title

reference date

date type

creation

effective date

1954-01-01

code identifying the extent

Inner Seas off the West Coast of Scotland

Extent group

authority code

title

reference date

date type

revision

effective date

2010-01-01

code identifying the extent

circalittoral

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

2007-08-05

End position

2007-08-17

Dataset reference date

date type

publication

effective date

2009-12-31

Frequency of update

notPlanned

Quality and validity

Lineage

IMPORTANT NOTE: The data is stored in OS Grid ref in Marine Recorder - here it has been transformed into lat long for entry into the bounding box tab for record validation purposes. This seabed data from the Treshnish Isles was collected by Heriot-Watt University for SNH between the the 5th August and 17th August 2007. Video images were obtained from 86 drop-down video drift tows (of the intended 107 video sites due to persistent windy conditions. Note: this resulted in a slight sampling bias in favour of the north half of the SAC), each approximately 3 min duration, onboard the vessel RV Serpula. The dropdown video system was replaced by diver-held video (Panasonic DX110B 3 chip digital video camera within a Seapro housing) at 12 of the 86 stations due to complex shallow channels. The video system used consisted of a Panasonic NV-GS150 3 chip digital video camera within a Seapro housing held within a frame and illuminated by twin 100 watt lamps. A 100 m umbilical cable carried the video signal to a Sony Video Walkman for real-time observation and for recording. At each station the camera was deployed briefly from a drifting vessel, noting the times, depths and precise positions at the start and end of the drift using differential GPS (dGPS). SNH contracted Heriot-Watt University to analyse the video footage to describe the physical structure and species assemblages present. Species present were identified and quantified using the semi-quantitative MNCR SACFOR scale, as far as possible. Where video runs traversed a sequence of biotopes, the runs are split into corresponding segments with the transition points recorded using time. Segmentation of runs was not practicable in the case of mosaics of recurring biotopes, in which case all biotopes observed were simply listed. Stations were also categorised as reef, non-reef or mixed habitats based on the presence of reef biotopes or a mixture of reef and non-reef biotopes. Reef biotopes were regarded as those falling under the higher biotope categories of Infralittoral Rock and Circalittoral Rock. Relocatable survey transects were established at 6 sites, chosen to represent the range of environmental conditions and biotopes found on intertidal and shallow subtidal reefs of the SAC. The position of the marker was fixed by dGPS and several photographs taken of it from different viewpoints, with the position of the camera recorded by dGPS and the bearing to the marker taken with a sight-bearing compass. The transect was split up into a series of zones which were defined in terms of differences in the composition of the biological community and or by changes in substrate type. All subtidal work was carried out with the use of SCUBA. A band 2 m either side of the tape was surveyed by two workers intertidally and two workers subtidally. Within each zone records were taken of substrate type and biota using the MNCR SACFOR scale of abundance, with collection of material for laboratory examination where in situ identification was not possible. Subtidally, a digital video camera (Panasonic DX100B in a Seapro housing) and a digital still camera (Canon 400D digital SLR with 17 mm wide-angle lens and Sea and Sea housing) were used to make representative visual recordings of the transect zones. Intertidally, the same video camera was used to record the zones, but the digital still camera was a KODAK DX6490. Where practicable, on the intertidal and subtidal components of each transect a zone of specific interest was selected for quantitative analysis. Within such zones a 10 m tape was laid perpendicular to the transect line, with the distance along the line (and the depth for subtidal zones) being recorded. 10 square, non-overlapping quadrats were placed randomly along the tape, using a set of random numbers and both sides of the tape. On the shore a quadrat of area 0.25 m2 was employed, whereas subtidally quadrats were 0.1 m2. Before examination each quadrat was photographed using a Canon 400D digital SLR and 17 mm wide-angle lens subtidally and a Kodak DX6490 intertidally. The biota within each quadrat was then enumerated using either counts or percentage cover estimates as appropriate.

Conformity

Conformity report

specification

title

reference date

date type

publication

effective date

2018-01-23

degree

true

explanation

See the referenced specification

Data format

name of format

version of format

Constraints related to access and use

Constraint set

Use constraints

Not for navigational use; This survey recorded no species or biotope occurrences that SNH consider as sensitive; all records may therefore be released in response to requests covered by Environmental Information Regulations or Freedom of Information Regulations; additionally its re-use and dissemination is permissible under Open Government Licence terms. Any re-use of this data will acknowledge the copyright owner.

Constraint set

Limitations on public access

No restrictions on public access

Responsible organisations

Responsible party

contact position

Teaching Fellow

organisation name

Heriot-Watt University School of Life Sciences

email address

dassh.enquiries@mba.ac.uk

responsible party role

originator

Responsible party

contact position

Data Manager

organisation name

Scottish Natural Heritage, Inverness

email address

data_supply@nature.scot

responsible party role

custodian

Metadata on metadata

Metadata point of contact

contact position

Data Manager

organisation name

Scottish Natural Heritage, Inverness

email address

data_supply@nature.scot

responsible party role

pointOfContact

Metadata date

2020-03-09

Metadata language