Follow-up measures

The objective of “passive acoustic” monitoring of marine mammals is to provide information on the activity of cetaceans in the area of ​​the offshore wind farm before work (reference state), during the construction, operation and dismantling phases.

Seven acoustic stations are positioned at different locations in the study area, each recording high frequencies (porpoises, clicks) and low frequencies (low and medium frequency cetaceans, ambient noise). Two stations are positioned in the park, and the other five are arranged in a star pattern around the park at 10 and 20 km distance.

Registration is effective 33% of the time. Equipment maintenance is carried out approximately every 3 months and the data obtained is processed back on land.

The objective of the measurement is to improve knowledge of the phenomenon of dispersal of adults and their chicks at sea, and to verify whether this dispersal is carried out in the direction of the wind farm off the bay of Saint-Brieuc.

The scientific protocol establishing the technical modalities of field actions was established jointly between Ailes Marines and local stakeholders (Bretagne Vivante and the Syndicat Mixte Grand Site Cap d'Erquy Cap Fréhel). Follow-ups will be carried out:

The observation data are used under GIS and will make it possible to produce a map showing the location of male-chick duos along the transects covered.

Monitoring of avifauna by maritime radar will be carried out using an automated radar/camera system, installed in the park, allowing maximum coverage of the park surface as well as good data acquisition. Vertical data provides information on flight height while horizontal data provides information on lateral trajectories/directions. These two pieces of information are important to see if the birds change their flight height, avoid the wind turbines laterally, enter directly into the park, and leave again.

The two main objectives are:

It was initially planned to install a radar during the pre-construction phase, construction and the first years of operation on a foundation, i.e. for 6 years. This is not possible for technical reasons (no offshore platform or electricity before commissioning). Ultimately, Ailes Marines will install 1 land radar during the migration period for 4 years (pre-construction and construction) and two radars at sea for 2 years.

Currently Micro Shelter Solution is working for Ailes Marines on the definition of this system (location, type of radar, coverage, dual navigation/avifauna vocation, configuration, maintenance, etc.) and the latter will be presented for information to the members of the CS.

The measure concerns nesting Torda Penguins and Common Guillemots in the Cap Fréhel colony. The aim is to clarify the ecology of these two species and to learn more about the behavior of these birds in relation to the construction and operation of the park.

The objective is to equip 10 to 15 individuals of Penguins and Guillemots per year, for 3 years, with miniaturized electronic devices during the breeding period.
Field work will take place at Cap Fréhel, with the birds immediately released on site as soon as the GPS is installed, then recaptured a few days later to recover the equipment. The data collected will allow detailed monitoring of their movements and their fishing activities in the Norman Breton Gulf.

The following deliverables will be produced:

Monitoring will be carried out in collaboration between the Regional Avifaune Observatory (ORA), Bretagne Vivante, the Caps union and the University of Nantes.

The objective of this monitoring is to evaluate the impacts of the construction and operation of the offshore wind farm and its connection on the fishery resource (monitoring shared with RTE. To do this, the comparison between the reference state and The environmental monitoring carried out throughout the life of the project must make it possible to decide on the effects of the project on the fishery resource.

Several follow-ups are implemented:

The list of species monitored goes beyond regulatory requirements, it has been validated with the Fisheries Committee 22 and includes the following species:

• Bentho-demersal species using a frank trawl (soft substrate) and a Canadian trawl (hard substrate);
• Large shellfish in the shellfish trap or shellfish net;
• Bivalves other than scallops at the Hamon bin;
• Scallops using a flap dredge (soft substrate) and a roller dredge (hard substrate);
• The whelks in the locker;
• Adult cuttlefish in the trap (on-board observations), as well as monitoring of spawning (laying of lines).

In addition to experimental fishing, on-board observation campaigns are carried out for most professions with professionals working in the bay of Saint-Brieuc, and more specifically in sectors close to the site of the future wind farm and its connection. . These campaigns (around 70 per year since the end of 2019) aim to obtain additional indicators.

The selection of stations was carried out in two stages:

• Areas more or less close to the field were selected to evaluate the impacts of the work and the operating phase according to a gradient of incidence
• Specific stations have been defined within its areas in consultation with the CDPMEM22 (in particular on the basis of knowledge of the fishing zones)

The objective of this measure is to monitor the risk of proliferation of crepidula by relay effect following the potential colonization of foundations. Indeed, the larvae of invasive species, such as the crepidula, could find a support at the foundation level which would act as a relay in the expansion of invasive species by offering new substrates for their installation. A monitoring measure specific to crepidula is therefore proposed in order to characterize their presence and the extent of colonization. In the event of a significant presence, a negative effect would then be noted, provided that their presence on the foundations induces an expansion of the crepidula shoal in Saint's Bay.

The results of monitoring the colonization of foundations (Reef Effect) will make it possible to identify the presence or absence of invasive species such as crepidula. Also, based on the results, specific monitoring of crepidula will or will not be implemented.

The monitoring measures will consist of these 3 steps:

In the operational phase, 8 wind turbines will be equipped with acoustic recording stations (ultrasound) in order to evaluate and characterize the activity of migrating bats in the park area.

This monitoring aims, among other things, to provide information on the presence of the Nathusius Pipistrelle migrating in the offshore wind farm. The latter having been detected at the Grand Léjon lighthouse but never in the park area.

This monitoring will also provide information on whether the wind farm in operation constitutes a source of light attraction for bats.

To do this, 8 wind turbines will be equipped with acoustic recording stations (ultrasound). These stations are distributed around the outskirts of the wind farm (see figure below).

The objective is to measure airborne noise on land during the construction phase during piling operations. The same measurement points as during the initial state in 2015 will be considered, namely:

• Point 1: Erquy
• Item 2: Binic

The measurements will be carried out throughout the duration of a threshing phase and a few hours before and after using a sound level meter per measuring point including a preamplifier and a microphone.

The measurements will be carried out in accordance with:

The objective of this measure is to validate that the photomontages presented as part of the impact study were representative of the reality once the park was installed.

Photographs will be taken at the locations selected for the production of photomontages as part of the project. Just like when making photomontages, for several points of view, variations will be made:

• Variations depending on weather conditions;
• Variants illustrating the perception of the night project if possible.

The photographs will be compiled into a report and presented to local authorities as well as members of the CGS. They will be taken at the following locations: