Cash and indicators

The Cybelle Mediterranean program is to follow the evolution over time of different indicators: species richness and / or abundance of species. More 35 4 Pelagic Species groups are studied: whale, fish, sea turtles, jellyfish.

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In the Mediterranean Sea, it is currently estimated that:

67% marine mammal species are threatened with extinction,

100% marine turtle species are threatened with extinction

8% fish species are threatened with extinction

41% species of rays and sharks and sharks are threatened with extinction

*Red List of Threatened Species, IUCN


Measure biodiversity

It is humanly and technically impossible to apprehend and monitor biodiversity as a whole, with at least 12 000 species identified in the Mediterranean! We therefore sought to have a realistic idea of ​​the situation by using biodiversity indicators and relevant indicator species. These indicators should give an idea of ​​the state of biodiversity and the pressures it is undergoing. 

The biodiversity indicators

The Cybelle Mediterranean program uses several kinds of indicators:

Species richness (richness). This indicator remains ambiguous enough to assess the biodiversity health since uninformative on environmental change. However, species richness is a good tool for measuring the health of a community.

The abundance. The abundance indicators are considered most suitable for monitoring biodiversity health. Indeed, they are sensitive to environmental changes in small and large scale. In addition to their scientific value, abundance offers an undeniable educational value. It allows contributors to have a concrete and understandable representation of the data collected. The collection of marine information does not offer the same observation conditions as on land. Observations are fleeting, diminished the visibility, decision more difficult rating, and the biggest hardware constraints. Thus the consideration of the actual abundance of species is very difficult, and remains a matter for specialists.

The indicator species

Indicator species are indicative of the search for a balance; their abrupt evolution, in one way or the other, reflects an imbalance and a problem of regulation in the functioning of the ecosystem.

Criteria for selection of species:

common species : Beyond rare species (which are the subject of many other studies), we wish to identify common species likely to be good indicators of biodiversity.

Species easy to identify by a neophyte : In order to limit the biases due to identification errors we have selected the species that are easier to identify,

Key cash vault : these are species that are at the heart of many specific interactions whose variation in abundance has an impact on the entire ecosystem,

The umbrella species Who need a large territory. By being protected, they protect species that occupy the same territory.

Species Ecological Interest Fauna recognized (ZNIEFF)

species susceptible to environmental variations (Eg, temperature-sensitive)

protected or "endangered" species

Species of interest for leisure or business.