Belfast Lough: from heavy industry to
mariculture
•
The Belfast Lough
Special Protection
Area (SPA);
–
•
The Belfast Lough
Open Water SPA;
–
•
designated for
overwintering (non
breeding)
Redshank.
designated for
overwintering (non
breeding) Great
Crested Grebe.
25 licensed
aquaculture sites of
which 21 are active
Aquaculture
•
Subtidal aquaculture sites for blue mussel
(Mytilus edulis) culture within Belfast Lough
•
The total area of Belfast Lough occupied by
aquaculture is approximately 1,270 hectares –
a third of the inner lough
•
Cultivation began in 1989. Belfast Lough is the
largest production area for bottom grown
mussels in NI
•
The production of bottom grown mussels
varied between 5177 t (2010) to 3458 t (2012).
•
In NI, aquaculture is now worth over €7.5
million annually, and the regulating
department is aiming to increase this sector by
30% by 2020.
•
Co-location with Natura 2000 sites
•
Beds are licensed and regulated by Department of Agriculture and
Rural Development
•
Activity is monitored and cumulative impact assessment
undertaken for Natura 2000 sites
•
Import/export to beds and dredging activity monitored via vessel
“black box”
•
Ecosystem modelling used to assess impact of blue mussel
cultivation on wild species and optimal stocking levels
Sustainable management
Activity
Seeding
Equipment
Modified Dutch
Dredge
Maintenance Starfish mop and
Modified Dutch
Dredge
Harvesting
Modified Dutch
Dredge
Timing
Usually Spring and
Autumn but is
dependent on seed
availability.
Throughout the year.
Market dependant as
stock is harvested to
order.
Unprocessed filtered data
Black Box data
•
Black box data is filtered in ArcGIS for:
– Speed;
– Location;
– Month .
•
Provides estimate of intensity (number of logged
positions per km²)
Processed filtered data
•
Used to ensure activity is restricted to licensed
beds and assess impact of activity on
conservation designations (Natura 2000 sites)
•
Application in the MSFD indicator “physical
damage” (part of Descriptor 6 – seabed
integrity), to provide information on physical
abrasion. This requires ongoing validation.
Bathymetry data
Multibeam echosounder
survey
•
EM3002 dual head data processed by British Geological
Survey to yield 1m horizontal resolution and <10cm
vertical resolution bathymetry and backscatter imagery
•
Backscatter provides information on seabed texture,
with seabed features evident including dredge scars
•
Use to validate black box data and assess persistence of
dredge marks on seabed
Backscatter data
BGS – White Ribbon survey (EM3002)
Backscatter mosaic (1m resolution)
BGS – White Ribbon survey (EM3002)
Backscatter mosaic (1m resolution)