Adriatic Grayling

Appearance

The Adriatic Grayling Valenciennes, 1848, known in Italian by the common name of Adriatic grayling, blue fin grayling or even Po river grayling, is a freshwater bony fish endemic to the Po basin and very few other rivers that flow into the northern Adriatic, seriously threatened with extinction.

Range and habitat

Habitats The Adriatic grayling is the only native species of grayling in Italy, as well as in the entire Adriatic basin, of that it is strictly endemic: its original distribution included all the main left tributaries of the Po, and those on the right between the source and the Parma. Therefore, in addition to Italy, the range also marginally included Switzerland (Canton Ticino) and Slovenia (Isonzo basin). Currently the species has been eradicated by man throughout its range, with a single population still viable, albeit threatened, located in Piedmont and the Adige valley.

GBIF currently lists 25 occurrence points. Those points follow where people logged the taxon — museum drawers and surveys included — not a closed range boundary.

Pins are Wikidata “endemic to” fields. Orange dots, when present, are GBIF occurrence tiles — survey bias included.

Diet

Salmonids need cold, oxygenated water and a clean gravel or open-lake feeding ground. Endemic whitefishes collapse when the lake is eutrophied or fished out.

In crisis

Adriatic Grayling, given the sudden decline it has undergone in recent decades that has brought it to the brink of extinction, was recently assessed as Critically Endangered (CR) by the IUCN. Among the main threats, we find hybridization with the European grayling (Thymallus thymallus), an alien fish repeatedly introduced into Italian waters, and still the subject of repopulation by sports fishermen. Even so, this is not the only threat to the bluefin grayling, that is above all threatened by the environmental alteration of watercourses, mainly caused by water abstraction, the artificialisation of rivers (dams, barriers, embankments), gravel extraction, but also by overfishing and pollution.

Adriatic Grayling is Endangered on this catalog because that is the IUCN category stored on Wikidata. Confirm the official criteria and any later count on iucnredlist.org.

Sources

Written for this catalog from the Italian Wikipedia article on Thymallus aeliani, translated and retold in English, plus Wikidata item Q50407493 and GBIF occurrence geography. Family and order context is original field-guide writing about the group. Wikipedia text is CC BY-SA. Not an IUCN assessment. Confirm status and range on iucnredlist.org.