Identification

Title

2015 Scottish Natural Heritage (SNH) North Rona sea caves site condition monitoring survey

Abstract

The purpose of this survey of North Rona SAC sea caves, undertaken on the 18th August 2015, was to initiate site condition monitoring (SCM). The objectives of SCM were to establish a baseline biological data set that would facilitate the assessment of the condition of habitats in the future and to allow a judgement to be formed on the current condition of these habitats in the light of existing SAC management measures. At 4 selected sea caves, detailed biological and physical surveys were conducted; the topography was mapped and the biotopes surveyed by MNCR phase 2 methodology at relocatable points along the cave system. Two other sea cave surveys were conducted as part of the same research cruise at St. Kilda SAC and Loch Eriboll.

Resource type

dataset

Resource locator

Unique resource identifier

code

GB-SCT-SNH-ME-000293-MRSNH0300000002D-NRONA

codeSpace

http://www.nature.scot

Dataset language

eng

Spatial reference system

code identifying the spatial reference system

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

Additional information source

Harries, D.B., Moore, C.G., Porter, J.S., Sanderson, W.G., Ware, F.J. & Kamphausen, L. 2018. The establishment of site condition monitoring of the sea caves of the St Kilda and North Rona Special Areas of Conservation with supplementary data from Loch Eriboll. Scottish Natural Heritage Research Report No. 1044.

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

2012-02-14

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

-5.9916

East bounding longitude

-5.6730

North bounding latitude

59.2272

South bounding latitude

59.0073

Extent

Extent group

authority code

title

reference date

date type

creation

effective date

2009-06-18

code identifying the extent

Scottish Continental Shelf

Extent group

authority code

title

reference date

date type

creation

effective date

2009-05-01

code identifying the extent

47E4

Extent group

authority code

title

reference date

date type

creation

effective date

1954-01-01

code identifying the extent

North Atlantic Ocean

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

2015-08-18

End position

2015-08-18

Dataset reference date

date type

publication

effective date

2018-12-31

Frequency of update

notPlanned

Quality and validity

Lineage

This sea cave data from North Rona was collected by SNH and Heriot-Watt University on the 18th August 2015. Detailed biological data and physical surveys were conducted at 3 cave sites. The intended criteria for selecting specific caves for detailed survey included the requirement that individual caves should represent the broadest available range of cave habitats (i.e. longer, extensive caves with a large depth range). Ideally, sites would also represent a wide range of environmental conditions (i.e. caves from different parts of the coasts, caves of differing exposure levels etc.). However, choice of sites was severely constrained by weather conditions. Where sea conditions were suitable, the coast was systematically examined at close quarters from an inflatable boat. All inlets, alcoves or other potential cave sites were investigated. Cave entrances were photographed and coordinates recorded. Where time and sea conditions allowed, the caves were entered by a snorkeler to gather information on passage length and main biota. The purpose of this exercise was to work towards developing a comprehensive inventory of the caves around North Rona. Monitoring surveys of caves were initiated by conducting a physical survey and deploying a relocatable fixed datum line for precise spatial mapping of biotopes. The physical survey addresses the attribute extent of cave(s). It also provides a means of defining the location of points within the cave from which biological data was recorded and enables those points to be relocated by subsequent monitoring surveys. 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. An approximate plan view sketch was produced of the cave floor with notes on the composition of the substrate. At selected points along the line the cross-sectional shape of the passage was sketched and the cross sectional dimensions (e.g. distance to floor, ceiling and both walls) was estimated in relation to the fixed datum line. An assessment was also made of changes in biological communities along the length of the cave and a series of locations were identified for subsequent collection of biological data from cross sections of the cave passage. Typically, two biological cross section surveys were conducted in each cave at the specified distances along the datum line. The biological surveys were conducted within a 2 m wide band up one wall of the passage. Where appropriate, the wall was subdivided into biological zones and the depth of the zone boundaries recorded. Within each biological zone, the abundance of each component species was estimated using the MNCR SACFOR scale and notes made on the nature and inclination of the substrate. Video footage was obtained along the length of the cave using the datum line for orientation and detailed footage was obtained of the biota at each of the biological cross sectional survey locations. Additional underwater wide angle and macro digital still images were taken to illustrate the biota at the biological cross sectional survey locations. Note: Excessive wave surge necessitated modifications to the methodology at a number of sites. Wherever possible, in-situ species identifications were validated by detailed cross-referencing with the identifications of the voucher specimens and with macro photographs. In-situ abundance records were also validated by detailed cross-referencing with video footage and stills images. Abundance scales were assigned using the MNCR SACFOR scale and biotopes were assigned. Similarly, site descriptions were cross-referenced with video and stills imagery for consistency and validation.

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 occurences that SNH consider as sensititive; 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 permissable 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

organisation name

Heriot-Watt University School of Life Sciences

email address

natmanta@hotmail.com

responsible party role

originator

Responsible party

contact position

Data Manager

organisation name

Scottish Natural Heritage (SNH), Headquaters

full postal address

Great Glen House, Leachkin Road

Inverness

IV3 8NW

telephone number

01463 725000

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 (SNH), Headquaters

full postal address

Great Glen House, Leachkin Road

Inverness

IV3 8NW

telephone number

01463 725000

email address

data_supply@nature.scot

responsible party role

pointOfContact

Metadata date

2020-03-12

Metadata language