This work is a qualitative analysis of the ornithological diversity in the area of Metauro river estuary and its lower course (Fano, Marche, Italy), a set of little wetlands of great birdlife conservation interest, defined in an urbanized context. Data collection took place through standardized censuses and ornithological observations in situ, from September 2010 to September 2020, integrated with an accurate bibliographic research on historical data. A total of 253 species have been recorded in the site; 59 (23.32%) breed in the area, whereas 50 (19.76%) species are vagrant and 72 species (28.57%) are included in the Annex I of the Birds Directive (79/409/CEE). We determined the following indices: NP/P (ratio between the number of species non Passerines and Passerines) = 1.94, O.V.I. (Ornithological Value Index) = 20.80. The data relating to species of conservation interest and vagrant are reported in detail, in order to provide useful information for interventions for greater protection of the area. The high ornithological diversity and species richness highlighted in this study confirms the regional and national importance of the Metauro river estuary and the wetlands in its lower course, providing further data and giving support to more incisive conservation interventions, made necessary by the ever-increasing impact of disturbance and low naturalistic protection, that threatens the existence of the various and small biotopes of this important naturalistic area.

An analysis of the observations of Boreal Owl Aegolius funereus in the Marche region, also regarding a recent recovery of an adult of the species, which appears to be the southernmost movement in Italy.