emerald gudgeon

The emerald gudgeon (Romanogobio skywalkeri) is a recently described fish species (Friedrich et al. 2018), which according to the current state of knowledge is endemic to Austria. As far as currently known, the species only occurs in the Upper Mur, where it inhabits gravel banks that are rapidly flooded.

The emerald gudgeon split off from its closest relatives several million years ago and is therefore significantly older than the other native endemic fish species. There is evidence that the R. skywalkeri is a relict species for which the Upper Mur, which was unglaciated during the last glacial maximum, served as a glacial refuge. The discovery of a new vertebrate species in Central Europe is remarkable from a scientific and ecological point of view and underlines the importance and value of the Mur and other alpine rivers as a habitat. However, very little is known about the biology of the species, except that it seems to have a higher oxygen demand than other native gudgeon species.

The project at the University of Graz, which is endowed with approx. EUR 84,000 and headed by Dr. Stephan Koblmüller started on February 1st, 2023.

In the project, the actual distribution of the emerald gudgeon is to be determined using water samples (eDNA and diagnostic qPCR based on the DNA barcoding region). For this purpose, mainly the tributary rivers of the Upper Mur are examined, but also other rivers on a random basis. Another goal is to determine population size and connectivity (using population genomic data). Since the species apparently has a very limited range, population size and subpopulation connectivity plays an important role in ensuring the long-term survival of the species. Last but not least, awareness-raising among the public and stakeholders should be carried out and the emerald gudgeon should be established as a flagship species.