In June 2020, the second article was published by REVIVO in Ribič (eng. Fisherman), the official magazine of the Slovenian Fisherman Association.

The article addressed the historical occurrence of sturgeons in Slovenia, specifically the sterlet (Acipenser ruthenus) and Russian sturgeon (A. gueldenstaedtii). The revision found reliable evidence of historical presence, such as photographs, scientific publications or even preserved specimens. Not surprisingly, the two largest sturgeon species, beluga (Huso huso) and ship sturgeon (A. nudiventris), were also recorded just across the border, merely 30 kms from Slovenia.

Before the construction of the Iron Gates dam in 1970, all sturgeon species migrated from the Black Sea to the suitable spawning habitats of Sava, Drava and other Danube tributaries to reproduce.

The latest record of a sterlet in Slovenia was confirmed in 2001 (Govedič & Friedrich, 2018) and the Russian sturgeon was last spotted in 1883 (PMS). The Sterlet is protected and listed in the Annex 1 (List of protected species of animals) and 2 (List of animal species whose habitats are protected) of the Decree on the protected wild animal species and in the Red list of Threatened species of Slovenia where it is categorised as rare. On the other hand, even though the Russian sturgeon was present in Slovenia in the past, it is not included or mentioned in any of these documents.

Other endangered and protected migratory species, targeted by the MEASURES project, Common nase (Chondrostoma nasus), Common barbel (Barbus barbus), Cactus roach (Rutilus virgo) and Vimba bream (Vimba vimba) were also presented in the article.

The initial steps of the habitat mapping were also described. Wintering and feeding habitats were identified via analysis of satellite photos (using Google Earth) and scanning the riverbed of Mura and Lower Sava River in Slovenia as it was already described in our MEASURES Interreg News (14st February 2019).

Both rivers were heavily regulated in the past, as evidenced by comparison with the military photos of the relevant stretches from the 19th century which were published in the article. The mostly natural river ecological corridor can be seen from these photographs from not so long ago.

… when Danube sturgeons were not one of the most endangered species in the world.

You can download and read the story, in Slovenian, by clicking HERE.