Seasonal changes in bird assemblages of a remnant wetland in a Mediterranean landscape: implications for management

Seasonal bird assemblages (both breeding and wintering) in a Mediterranean remnant wetland were described by a sample-based approach. Species richness, diversity index and the number of equally common species had higher values in winter than during the breeding period. At the guild level, wetland-related species were more represented in winter, either in terms of species richness or of frequency of occurrences. In winter, the availability of food resources related to seasonally flooded areas and the increment of the habitat heterogeneity increased the species richness and diversity, especially for wintering wetland-related species. The nature of the study area, a small remnant wetland embedded in a man-disturbed and land reclaimed landscape, explains the high rate of synanthropic species either in terms of richness or frequency of occurrences. Among these species, the Italian Sparrow (Passer italiae) was observed to use intensively the rush beds (Juncetalia maritimi habitat type) during the breeding period for foraging and fledging, owing to the abundance of suitable prey. Although these latter results require further studies, the utilization of wetlands by a declining Italian endemic, the Italian Sparrow, evidenced as these type of habitat may contribute to conserve threatened species other than waterbirds, providing support during the breeding season. Key words: wintering season, breeding season, synanthropic species, matrix effect, Passer italiae.