Shellfish and Co 🐚 ...... examined under the microscope by the SETEC IN VIVO design office

Setec In Vivo unveils the results of studies related to species living on and in the seabed, known as benthic biocenoses. Conducted from 2012 to date, the objective was to identify their presence and distribution in order to ultimately determine the environmental impact of the implementation of an offshore wind farm in the Bay of Saint-Brieuc.

These studies continued after the permits were obtained and were completed with, in particular, bibliographical studies on the effects of turbidity and laboratory studies on the effects of noise on these communities.

🔎 What are benthic biocenoses?

Benthic biocenoses are organisms living in connection with the seabed.

We speak ofendofauna* when the species are in the substrate, such as certain shells that live buried in the sand, andepifauna* when the organisms live on the seabed, such as brittle stars or sea urchins.

  • PEpifauna

    Epifauna is the name for the biology of bottom-dwelling aquatic animals, benthos, living in fresh or salt water, as well as terrestrial animals living on vegetation or even on another animal.

  • PEndofauna

    The termendofauna is used for animals living inside loose substrates. By extension, endofauna is also used for animals living inside a benthic animal.

Study and results

  • PAn accurate inventory

The surveys carried out identified the species present and their distribution in the project area.

In the centre of the siting area, for example, there is a carpet of brittle stars, as well as coarse gravelly sediments with venereal bivalves over a large part of the potential siting area.

On the other hand, algal biocenoses are very little present in this area.

  • PThe consequences of the construction of the park in the defined area

Once this inventory had been completed, the impact study made it possible to define a priori the potential impacts of the project on the environment during the construction phase and during the park's operation.
During the construction phase, several potential impacts were characterised.

However, it is important to specify that these impacts will be limited in space and time. The modelling and bibliographical studies carried out on turbidity by a group led by Actimar have demonstrated a low impact on the environment. As for the potential effects of noise on organisms, recent and unpublished studies carried out in partnership with the CNRS have shown that noise during the construction phase is not likely to kill scallops.

In the operational phase, a positive effect is expected with the reef effect.

SETEC IN VIVO continues its monitoring

The monitoring of the effects and consequences of the construction of the offshore wind farm is necessary in order to evaluate the strict effects of the project. Therefore, many means are used to measure the effects of the project on the environment.

SETEC IN VIVO will restart its data collection by monitoring benthic biocenoses. This marine exploration will allow the analysis of a possible ecological change.