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) Temporal variability in stressors/effectors 3. Decommission 2. Operation GE wind energy
Types of interaction and impact framework (modified from Boehlert & Gill 2010)
Schlalldruck in kpa 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 Sedentary species Mobile (pressure and species particle motion) marine marine 4 3 Spitzenschalldruck ca. 3400 Pa 2 1 0-1 -2-3 -4 0.00 0.05 0.10 0.15 0.20 Zeit in Sekunden
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)
Operation- Potential habitats and physical factors linked to fish distribution Surface zone Pre-OWF Eddies Post-OWF Up to 50m P e l a g i c Current Current T i d e Colonised Colonised hard http://www.mywindpowersystem.com/ hard lattice substrate substrate Z o n e Tides Photo by: Clover Tides Refuge Bentho- Demersal Eddies zone Seabed hard or soft substrate Scour protection zone hard http://www.mywindpowersystem.com/ substrate with crevices/holes ABGill
Operation- Potential habitats and physical factors linked to fish distribution Surface zone Pre-OWF Eddies Post-OWF Up to 50m P e l a g i c Current Current T i d e Colonised hard substrate Colonised hard lattice substrate Z o n e Tides Tides Refuge Bentho- Demersal Eddies zone Seabed hard or soft substrate Scour protection zone hard substrate with crevices/holes ABGill
Operation Hard substratum / artificial reef? Epifauna Telmatogeton japonicus Mytilus edulis Balanus crenatus Balanus balanus Jassa marmorata Asterias rubens Caprella linearis Metridium senile Sargartia troglodytes Sargartiogeton undatus Crepidula fornicata Jassa marmorata Tubularia indivisa Cancer pagurus Pagurus bernhardus Strongylocetrotus droebachiensis Copied from Offshore Windfarm & Environment Conference 2004, Denmark
Individual cod acoustic detection
Claisse et al. (2014) Fish Biomass local increase OWF changes to Fish community Variability in recruitment Cumulative effects multiple turbines and OWF sites
Ecosystem change - Interactions and energy flow within the fish assemblage pre and post OWF Surface zone plankton Aerial predators Pre-OWF Post-OWF plankton Aerial predators littoral* Pelagic fish Pelagic fish Predators Organic import Photography by Michael AW Predators Demersal fish Photo: DTU Aqua/FIS Organic export Up to 50m Demersal fish Organic input Bentho- Demersal zone http://www.mareano.no/ Benthos Decomposers from Offshore Windfarm & Environment Conference 2004, Denmark Organic input Benthos Decomposers ABGill
Ecosystem change - Interactions and energy flow within the fish assemblage pre and post OWF Surface zone plankton Aerial predators Pre-OWF Post-OWF plankton Aerial predators littoral* Pelagic fish Pelagic fish Predators Photo: DTU Aqua/FIS Organic import Predators Demersal fish Organic export Up to 50m Bentho- Demersal zone Demersal fish Organic input Benthos Organic input Benthos Decomposers Decomposers 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: pangalia@mail.com www.pangalia.com