Spring raptor migration at Ustica, southern Italy

The island of Ustica, lying at 38°42’N 13°12’E in the Tyrrhenian Sea, is approximately 60 km north of western Sicily and 270 km northeast of the Cap Bon promontory in Tunisia (fig.1). Although covering an area of only 7,600 ha, its isolation makes it attractive to migrant birds. In order to establish the importance of Ustica for the spring migration of raptors in the Mediterranean basin, counts of migrating raptors were made from the highest point of the Falconiera promontory, which dominates the northeast coast of the island, between 22nd March and 20th May 2002.Each spring, thousands of raptors cross the Mediterranean Sea between Africa and southern Italy during their northward migration to European breeding areas. Within this region, the largest concentrations have been reported at the Strait of Messina, between southern mainland Italy and Sicily (fig. 1). Corso (2001) documented an average of 26,062 raptors migrating across the Strait of Messina each spring between 1996 and 2000 (table 1). At this site, raptors crossing the Strait of Sicily, between the Cap Bon peninsula and western Sicily, converge with those migrating northTable 1. Number of raptors observed on Ustica, southern Italy, from 22nd March to 20th May 2002. These are compared with those recorded at the Strait of Messina during spring migration 1996-2000, based on data from Corso (2001). Species Honey-buzzard Pernis apivorus Black Kite Milvus migrans Short-toed Eagle Circaetus gallicus Marsh Harrier Circus aeruginosus Hen Harrier Circus cyaneus Pallid Harrier Circus macrourus Montagu’s Harrier Circus pygargus Pallid/Montagu’s Harrier Circus