Review of European studies:
impacts of offshore wind
development on fish(es)
Andrew B Gill PhD FRSB
Dan Wilhelmsson PhD
PANGALIA
Environmental
The OWF context
Offshore Wind Development Phases
1. Construction (& survey)
2. Operation
©GE wind energy
3. Decommission
Temporal variability
in
stressors/effectors
Types of interaction and impact framework (modified from Boehlert & Gill 2010)
IMPACT PREDICTION
SOURCE PATHWAY RECEPTOR
Table 1. An example of identifying and representing the S-P-R linkages regarding the generation of underwater noise during construction of renewable energy devices.
Hazard Source Pathway Receptor
Pile Driving Noise
Construction of renewable energy device
Underwater acoustic transmission (pressure and particle motion)
Sedentary marine species Mobile marine species
0.00 0.05 0.10 0.15 0.20
Zeit in Sekunden
-4
-3
-2
-1
0
1
2
3
4
Schla
lldru
ck in k
Pa
Spitzenschalldruck ca. 3400 Pa
Zones of noise influence
Herring and
cod: ~ 80 km
Dab and
salmon: many
kilometres
Close to
source (up ~
200 m)
Possible consequences of disturbance
• Predicted effect -
• Displacement from spawning
and / or fishing grounds
• Reduced reproduction and survival
• Reduced catches
• Changes to fish distribution (sandeels)
causing associated changes in predator
• Fish eating seabird (little Tern)
• Egg abandonment and low chick
hatching locally
(Herring map from Coull et al. 1998 currently updated by Cefas)
Eddies
Eddies
Current
Tides
Surface zone
Bentho-Demersal zone
Pelagic Zone
Refuge
Up to 50m
Colonised hard substrate
Scour protection zone – hard substrate with crevices/holes
Current
Operation- Potential habitats and physical factors linked to fish distribution
Pre-OWF Post-OWF
Tides
Tide
Seabed – hard or soft substrate
Colonised hard lattice substrate
Photo by: Clover
© ABGill http://www.mywindpowersystem.com/
http://www.mywindpowersystem.com/
Eddies
Eddies
Current
Tides
Surface zone
Bentho-Demersal zone
Pelagic Zone
Refuge
Up to 50m
Colonised hard substrate
Scour protection zone – hard substrate with crevices/holes
Current
Operation- Potential habitats and physical factors linked to fish distribution
Pre-OWF Post-OWF
Tides
Tide
Seabed – hard or soft substrate
Colonised hard lattice substrate
© ABGill
Operation – Hard substratum / artificial reef?
• Epifauna
Mytilus edulis
Balanus crenatus
Balanus balanus
Jassa marmorata
Cancer pagurus
Pagurus bernhardus
Strongylocetrotus droebachiensis
Asterias rubens
Caprella linearis
Metridium senile
Sargartia troglodytes
Sargartiogeton undatus
Crepidula fornicata
Jassa marmorata
Tubularia indivisa
Telmatogeton japonicus
Copied from Offshore Windfarm & Environment Conference 2004, Denmark
Individual cod acoustic detection
Fish Biomass – local increase
Claisse et al. (2014)
OWF changes to Fish community • Variability in recruitment • Cumulative effects – multiple
turbines and OWF sites
plankton
Aerial predators
Decomposers
Pelagic fish
Demersal fish
Surface zone
Bentho-Demersal zone
Up to 50m
plankton
Ecosystem change - Interactions and energy flow within the fish assemblage pre and post OWF
Pre-OWF Post-OWF
Predators
Benthos
Organic input
Aerial predators
Decomposers
Pelagic fish
Demersal fish
Predators
Benthos Organic input
littoral*
Organic export
Organic import
Photography by Michael AW
http://www.mareano.no/
Photo: DTU Aqua/FIS
© ABGill
from Offshore Windfarm & Environment Conference 2004, Denmark
plankton
Aerial predators
Decomposers
Pelagic fish
Demersal fish
Surface zone
Bentho-Demersal zone
Up to 50m
plankton
Ecosystem change - Interactions and energy flow within the fish assemblage pre and post OWF
Pre-OWF Post-OWF
Predators
Benthos
Organic input
Aerial predators
Decomposers
Pelagic fish
Demersal fish
Predators
Benthos Organic input
littoral*
Organic export
Organic import
Photo: DTU Aqua/FIS
© ABGill
Decommissioning - Renewables to reefs?
Qs relating to Fish community - • Should turbine foundations
be removed at the end of the assets life?
• What percentage of decommissioned turbines would expect to turn in to reefs?
• Trade offs – biodiversity, de facto MPA, fisheries ?
Source: Fowler et al 2018
Summary
• Offshore wind turbine developments WILL affect fish – consider possible outcomes (+, -, 0) to determine impact
• Fish associate with OWF - community structure may alter leading to changes in trophic interactions within local ecosystem
• Temporal and spatial use may differ with life history stage
• Targeted collaborative research/monitoring essential - to address unknowns and reduce uncertainty particularly
understanding the significance of consequences
Thanks & Very happy to talk further :
Andrew B Gill PhD FRSB PANGALIA Environmental email: [email protected] www.pangalia.com