How were inventories carried out?
We have identified priority sites for study with local actors, the local authorities of Corsica, the Corsica Environment Authority, the Regional Natural Park of Corsica, the Greenhouse of the Coast, the National Office of Forests and the French Biodiversity Authority. At each site, large groups of 20 to 40 people have been created, consisting of researchers and amateurs. For the terrestrial environment, collection was done primarily with interceptor traps (such as Malay tents) and decoy traps (such as light traps), as well as colored water-filled plates simulating flowers and traditional nets and braids. The teams also used automatic traps, which they left for a whole year to be able to observe the seasonal changes in the fauna.
In the marine environment, they walked with trawls and small dredgers so as not to damage the bottom. There were also many diving collections with underwater vacuum cleaners and brush baskets that collect any organisms that have settled in rock crevices and are invisible to the naked eye even to an experienced naturalist.
Exploration is only a small part of the job. First of all, it is a matter of sifting and sorting, since most of the biodiversity is small. The field time is not the identification time. Efforts are dedicated to sampling and preparing collected specimens for later study and conservation.
What is Planet Revisited in Corsica’s score to date?
We are in a territory that is quite exceptional in terms of the Mediterranean. The expedition confirmed the great richness of Corsica in terms of habitats and species present. For the offshore section, 1100 species were identified in situ and 4300 specimens were retained for sequencing. For the terrestrial component, 1750 species have been identified and 2200 specimens have been preserved. Among the collected animals, 7 species new to science were identified, including a species of wasp. It was a surprise to discover new species in Corsica. Thanks to DNA sequencing, we will also be able to detect cryptic species, that is, species that have a similar morphology but are very different from a genetic point of view. This is common in certain groups such as marine clams. The collection also led to what is called new records: we found species that exist elsewhere but have not been recorded in Corsica, such as Vitrea diaphanland snail, as well as species that were inventoried long ago on the island and which have not been seen since their description, such as Phyllodromic subapteraa cockroach that hasn’t been seen in 50 years.
What benefits can be expected from these large reserves?
From a research point of view, you are accelerating the inventory of biodiversity by involving many people. It’s a bit of Taylorism. We have a whole chain of operations that allows us to quickly sort and organize.
Inventorying will help us better understand the evolution of organisms. The Mediterranean Sea is a real crossroads between Africa, Europe and the Middle East. Its fauna and flora are of diverse and complex origins. By comparing the DNA sequences of species collected with data from international databases, we can better understand their origins.
These expeditions also represent a human adventure. The interaction between managers, researchers and hobbyists generates many discussions that will eventually lead to collaboration.