Since several years, ECOMERS collaborates with IUCN within several specialist groups. Several contributions to the Red List have been produced (see the complete list in the "Read more" section). In November 2018, the IUCN Red List of Threatened Species published the new global assessments on Groupers. ECOMERS contributed to the status evaluation 6 of these species: the White Grouper (Epinephelus aeneus), the Dogtooth Grouper (E. caninus), the Goldblotch Grouper (E. costae), the Dusky Grouper (E. marginatus), the Haifa Grouper (Hyporthodus haifensis) and the Mottled Grouper (Mycteroperca rubra).

Two species are considered as Data Deficient, E. caninus, E. costae, two as Least Concern, H. haifensis, M. rubra, one as Near Threatened, E. aeneus, and one as Vulnerable, E. marginatus. The previous status of E. marginatus, the most important species within the Mediterranean basin, was Endangered. This change from EN to VU status does not prove that there are some improvements of the status of the dusky grouper. The population trend is clearly decreasing on its whole geographic distribution. However, the change in status from the previous assessment reflects an improved application of the IUCN Red List Categories and Criteria, as well as a better understanding of available data. It means that further research is needed on its population status, especially in the southwestern Indian Ocean, the southwestern Atlantic and West Africa, and actions that reduce fishing effort are greatly needed. Similarly in the Mediterranean, more research efforts have to be deployed to assess the current fishing effort on this species.

It is also important to highlight that these 2018 status evaluations for the Grouper species are global, i.e. considering their whole geographical distribution. At a regional scale, the Mediterranean, the present status of the Dusky Grouper is still Endangered.

CREOCEAN and GEOLAB companies are developing a methodology and know-how in underwater photogrammetry. The objective is to reconstruct in 3D as accurately as possible objects immersed from series of underwater photos. A modelling of the 3D printed artificial reefs immersed in Larvotto Marine Protected Area has been recently conducted in collaboration with AMPN and ECOMERS. The main objective is to compare the theoretical model used for 3D printing with the model reconstructed by photogrammetry. This modelling could be integrated into the work conducted by Elisabeth Riera as part of her doctoral thesis on the evaluation of the tridimensional complexity of all types of artificial reefs. Ultimately, this technique can also be applied in other areas of research.

Photo P. Francour: underwater photography of a 3D printed artificial reef. Several hundred of photos are necessary to reconstruct by photogrammetry a tridimensional object.

Photo CREOCEAN: the first reconstruction by photogrammetry of a Larvotto 3D artificial reef.

Monitoring of marine benthos with an hyperspectral camera: a first in the Mediterranean

Habitat destruction is one of the main causes of the decline of marine biodiversity and fisheries resources. An artificial reef can be considered as a tool to protect or restore these habitats and their declining biodiversity. The Barcelona Convention defines artificial reefs as "structures specifically built to protect, regenerate, concentrate and / or increase the production of biological marine resources, whether for fishing or nature conservation, which includes the protection and protection of the environment. regeneration of habitats ". In response to these problems, nearly 88,000 m3 of artificial reefs, mostly made of concrete, have been deployed on the Mediterranean coast of France for some thirty years. To date, the assessment of reef performance has focussed primarily on fish communities and has almost completely ignored the development of epibiosis (biofilm and macrofouling). Historically in the Mediterranean, the first published works in the 70s deal with the species of macrofouling. Thereafter, during the last decades, most of the works focussed on the fish assemblages. However, the biofilm (mainly bacteria and unicellular micro-algae) and macrofouling (mostly algae and fixed invertebrates) are the first elements of the food web that will allow the installation and development of the fauna of large invertebrates (crustaceans) and fish on or around artificial reefs.

In November 2017, 6 large 3D printed artificial reefs were immersed in the Larvotto marine protected area (Monaco). ECOMERS and BOREA (Museum of Natural History of Paris), in collaboration with AMPN, launched a long-term monitoring of these reefs, including an analysis of biofilm and macrofouling.

To answer this, an innovative technique is being tested with the use of an immersible hyperspectral camera. This camera is developed by PlanBlue, a start-up from the Max Planck Institute (Germany). Briefly, hyperspectral imaging is a technique combining imaging and spectroscopy where each image is taken for a narrow band of the electromagnetic spectrum. For example, the human eye sees light in three bands (red, green, and blue) while hyperspectral imaging can 'see' in a very large number of bands typically ranging from visible to near infrared. Each species has a particular signature (hyperspectral image) that can be used to identify it. The development of a submergible camera allows to acquire underwater scuba images of different substrates colonized and thus to quickly have a precise identification (species or genus) of the species present. This speed and ease of identification are the main highlights of this camera. Once the validation is done (association between a light spectrum and a species or group of species), it will then be easy to determine the composition of the macrofouling species. Moreover, this promising technology go further than the simple identification of species. This camera can also give information about the physiological activities of photosynthetic species growing over the time.

This innovative technique has never been used in the Mediterranean. Its development in Monaco by ECOMERS and AMPN in partnership with CREOCEAN and its validation as a method of monitoring the macrofouling will be a first. This technique could subsequently be used in the monitoring of the benthos, whether on artificial or natural substrate. The prospects of application far exceed the only artificial reefs.

Photos P. Francour: Test and calibration of the hyperspectral camera in shallow habitats