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Certain presence

Corresponds to a report on the basis of at least one observation proved within a period of 10 years (20 years for little-known invertebrates) preceding the year and no presumption of extinction since obtaining the last data nor doubt on reproductive and implemented nature of this population. For migratory species, the presence indicated concerns areas of reproduction.

Probable presence

This status is based on one or more of the following criteria:

• search of species incomplete but presence of supportive environments;
• ecology of the species consistent with the hypothesis of his presence;
• the last reliable sighting is older than 10 years compared to the reference date, no recent specific research and no presumption of extinction from that date [vertebrates, invertebrates and plants well studied (rhopalocera, grasshoppers, dragonflies ...)] ;
• the last reliable observation being older than 20 years, no recent specific research and no presumption of extinction from that date [poorly known taxa: fungus, many invertebrates...].

Probable or certain absence

This point covers the absence, more difficult by nature to demonstrate than presence. This status is based on one or more of the following criteria:

• intensive but unsuccessful targeted research;
• lack of adequate environments;
• unobserved species while its presence is easily detected;
• unlikely presence for historical or biogeographical reasons.

This status must be assigned to a department in which the presence of the species is casual.

Absence due to a proven extinction

Particular case of absence due to a proven extinction less than a half century ago (older disappearances are treated as "no probable or definite").

No information

In the state of knowledge, we can not comment on the presence or absence in the current department. This is the default status when not comprised in one of the previous categories or whenever there is doubt.

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