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MARCH 2007 SHORT COMMUNICATIONS 59

Table 1. Number of flocks of European Honey-buzzards Table 2. Number of flocks of European Honey-buzzards
recorded, and number of hours observed, 25 April–20 May recorded, and number of hours observed at migration
2004, at migration stations at Pantelleria and Marettimo stations, 25 April–20 May 2004, at the Straits of Messina
islands, central Mediterranean Basin, as a function of and Panarea Island, central Mediterranean Basin, as
prevailing wind direction and time of day. a function of prevailing wind direction and time of day.

FLOCKS *{ HOURS * FLOCKS *{ HOURS
PANTEL- MARET- PANTEL- MARET- STRAITS OF STRAITS OF
FACTOR LERIA TIMO LERIA TIMO FACTOR MESSINA PANAREA MESSINA PANAREA
Prevailing winds Prevailing winds
N-NNE 96 14 39 42 N-NNE 594 127 135 146
W-WNW-NW 111 67 123 107 WSW-SW-SSW 124 68 39 35
WSW-SW-SSW 9 24 78 30 Time of day
Time of day Morning 244 82 101 82
Morning 28 10 88 52 Midday 327 70 98 103
Midday 42 62 99 78 Afternoon 224 74 68 68
Afternoon 146 37 78 49
* 5 P , 0.05 for prevailing winds.
* 5 P , 0.05 for prevailing winds. { 5 P , 0.05 for time of day.
{ 5 P , 0.05 for time of day.
gration showed an evident peak during the afternoon at 5 2, P , 0.05; Table 2). Among flocks recorded at Pa-
Pantelleria and during midday at Marettimo (x 2 5 47.19, narea, at least 31 (13.7%), containing 1290 (30%) birds,
df 5 2, P , 0.01; Table 1). bypassed the island, flying directly toward Stromboli, ap-
Straits of Messina–Panarea. 795 flocks were recorded parently coming from the island of Salina (Fig. 1). They
at the Straits of Messina (in 267 hr of observation), 226 were seen using soaring flight over the sea, probably flying
flocks at Panarea (in 253 hr of observation), and 186 and in thermals deviated over water by the wind (see also Agos-
88 birds migrated alone at the two sites, respectively. Flocks tini et al. 2005a) but, apparently, their altitude was never
contained 11 509 and 4210 birds, with an average flock size higher than our observation post.
of 14.2 6 0.6 (SE) and 20.1 6 2.2 (SE) birds, respectively Finally, it is interesting to note that the proportion of
(maximum flock size was 227 at Panarea). In this region, flocks reported during south-westerly winds was higher at
prevailing winds were from N-NNE and WSW-SW-SSW. Al- the Straits of Messina–Panarea than at Marettimo–Pantel-
though at both sites European Honey-buzzards were seen leria (x 2 5 27.29, df 5 1, P , 0.01, Table 3), although,
mostly during N-NNE winds, the proportion of flocks re- during such wind conditions, a greater proportion of the
corded at Panarea during south-westerly winds (34.9%, N hours of observation was made at the last two locations (x 2
5 195) was higher than that recorded at the Straits of 5 15.27, df 5 1, P , 0.01, Table 3).
Messina during such atmospheric conditions (17.3%, N
5 718; x 2 5 27.33, df 5 1, P , 0.01, Table 2). The circa- DISCUSSION
dian variation of the migratory flow differed at the two European Honey-buzzards crossing the southern and
sites; the peak occurred during midday at the Straits of northern side of the Channel of Sicily, via Pantelleria
Messina, during the morning at Panarea (x 2 5 7.65, df and Marettimo, used the same pathways they did during

Table 3. Number of flocks of European Honey-buzzards recorded, and number of hours observed, 25 April–20 May
2004, at the two study areas during south-westerly and other wind directions.

FLOCKS * HOURS *
STRAITS OF MARETTIMO– STRAITS OF MARETTIMO-
FACTOR MESSINA–PANAREA PANTELLERIA MESSINA–PANAREA PANTELLERIA
Prevailing winds
Other winds 603 292 446 336
WSW-SW-SSW 192 33 74 108
* 5 P , 0.05 for prevailing winds.