Nuovi dati sulla distribuzione di Aphanius fasciatus (Valenciennes, 1821) nella ZSC/ZPS IT3330005 "Foce dell'Isonzo - Isola della Cona" (Friuli Venezia Giulia)

Abstract - The present study is a contribute to the knowledge of the Aphanius fasciatus distribution within the ZSC (SAC)/ZPSIT3330005, “Foce dell’Isonzo - Isola della Cona”. To obtain quantitative data, fish have been sampled using a seine in eight sites within the ZSC (SAC) boundaries, partially overlapping with those of the Natural Regional Reserve of the Isonzo River Mouth. Monitoring activities have been carried out from May to November for two years (2015-2016) and allowed to gain information about presence and densities of Aphanius fasciatus within the sandbank zone at the center of the SAC, with mean densities equal to 7,25±6,44 ind/100m2 in 2015 and to 8,75±14,90 ind/100m2 in 2016. Present data allow to define the distribution areas of A. fasciatus within the studied environment and represent a useful series of information to comprehend the population dynamics for the considered species, listed in the Annex II of the Habitat Directive 92/43/EC and in the Annex III of the Bern Convention on the Conservation of European Wildlife and Natural Habitats.