Storm petrels were recorded along a transect line in the Strait of Gib
raltar from August to the middle of November and in December. No hint
for migration of the Mediterranean population through the Strait could
be revealed. The presence of Storm Petrels is enhanced in October/Nov
ember. Throughout autumn about 82 % of the Storm Petrels steadily flyi
ng east or west flew east. Estimates yield only 1100-1700 storm petrel
s leaving, but 6300-9500 entering the Mediterranean during daylight, w
hile about 12,000 pairs are known to breed in the Mediterranean.