Distribution and abundance of bullhead (Cottus gobio L.) populations in waters of east Emilia-Romagna region (Italy)

The river bullhead (Cottus gobio L.) is defined as a “Low Risk” species by the IUCN, but is very sensitive to changes and decreasing of environmental quality of living habitats, in particular due to riverbeds artificialisation. Moreover, the species is severely threatened by the predation on juveniles by trouts released into watercourses for fishing. The aim of this research is to analyse river bullhead populations describing their distributions and abundances and looking for biotic and abiotic factors that may influence them. The study area is extended along the eastern sector of the Emilia-Romagna region and includes from east to west the following river basins and sub-basins: Savio, Fiumi Uniti, Lamone, Reno, Panaro and Secchia. The research was carried out collecting fish fauna from 77 sampling sites of 27 different watercourses distribuited at more than 300 meters height above the sea level. The obtained results, compared and integrated with the use of Regional Italian Journal of Freshwater Ichthyology, 2014 vol. 1 Atti XIII Congresso Nazionale Associazione Italiana Ittiologi Acque Dolci – Sansepolcro (Ar) 312 Ichthyological Cards, provide a synthetic vision on the real distribution of river bullhead in the Adriatic sector of the eastern Tosco-Emiliano-Romagnolo Appennines and add information about their populations structure and abundance