Gwynt y Môr Study

Ecostructure is planning an investigation into the use of the Gwynt y Môr windfarm by commercially important species such as lobster, brown crab and Atlantic cod. Researchers from the Ecostructure project will be placing a buoy into the area in May 2021 and tagging these species to determine how they use wind farms and if wind farms have an influence on their abundance.

About the Study

As documented in the North Sea, offshore renewable energy structures can have ‘reef effects’ as a function of the scour protection that is often placed around these structures. This may lead to an increase in the abundance of crustaceans and demersal fish. An increased abundance of these species has the potential to benefit local fisheries — and therefore local economies — through this ‘spill-over effect’. To investigate the potential spill-over and reef effects of the Gwynt y Môr site, we will be using acoustic telemetry to track the movements of a number of commercially important  species. This will provide location-specific information that will help us to identify key habitat features within the site and begin to build a catalogue of how each species interacts with the site.

Photo: Team Sheehan, Plymouth University, 2020

Photo: Team Sheehan, Plymouth University, 2020

Acoustic Telemetry

Acoustic telemetry involves 2 pieces of equipment: an acoustic transmitter, which is attached to the study species, and an acoustic receiver, which is attached to a surface buoy. With lobsters and crabs, transmitters will be externally attached (see photos above), while Atlantic cod will have the transmitter implanted into the gut cavity.

Any organism included in the study will be easily identifiable by the external ID tag attached to crustaceans and T-bar tags attached to Atlantic cod. If you have caught an organism involved in this study please contact Harry Thatcher (

The acoustic receivers will be deployed using a simple mooring with a surface buoy. Whenever a tagged animal is within 300m of a receiver, the receiver will  log the signals transmitted from the tag from the transmitter (transmitters beyond 300m will not be detected). We plan to deploy 30 of these moorings in 3 groups of 10.   This will provide researchers with fine scale (1m) information of the movement patterns of the tagged animals over an area of 50,000m2.

Key Information

Moorings and receivers will be deployed for the first time in early May 2021 and removed in late October 2021. We then intend to repeat this throughout the same months during 2022 & 2023.

We are at the early stages of planning for this project but we are keen to keep stakeholders and area users aware of what we are doing, why we are doing it and how we are doing it. We will therefore be providing regular updates as the project develops.

If you use the Gywnt y Môr site for commercial or recreational fishing and think this project may effect your usual activities please contact Harry Thatcher or Dr. David Wilcockson