Page 3 - Corso_Cardelli _2004

Migration of Pallid Harrier across the central Mediterranean

Andrea Corso

140. The Strait of Messina, southern Italy, from Capo Peloro, at the northeastern tip of Sicily; this site is
good for counting migrant harriers Circus crossing the Strait, especially in poor weather (see text).

Results spring 2001, when 132 were counted during
Migration of Pallid Harriers at the April-May (plus another 20 during February-
Strait of Messina March), was clearly exceptional (Corso in
Between 1984 and 2001, a total of 459 Pallid prep.). Early migrants, in February-March, and
Harriers were observed during the spring those observed at nearby sites which are not
migration (fig. 2). During this period, our data part of the Messina project, are not included in
show a marked increase in the numbers fig. 2, so the true numbers using this flyway are
recorded in spring, with a mean 6.7 birds per clearly greater than fig. 2 suggests.
year between 1984 and 1993, and a mean of The increase shown may be due in part to
49.0 per year during 1994-2001. We estimate better knowledge of the field identification of
that the number of northbound Pallid Harriers small harriers in recent years, which means a
has been 100+ per spring since about 1998; greater proportion of females and immatures

150

100

50

0
84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01
Fig. 2. Numbers (total) of Pallid Harriers Circus macrourus recorded in spring (April and May), Strait of Messina,
southern Italy, 1984-2001. A grand total of 459 individuals was recorded in these 18 years (mean = 25.5, range:
0-132). During 1998-2001, counts were also made in February-March (Cardelli & Corso in prep.) but these are
not included in fig. 2. Furthermore, in 1998, 45+ Pallid Harriers were recorded from a site close to
our study area (see text); these are also not included here.

240 British Birds 97 • May 2004 • 238-246