Birds. 1113 



A List of the Migratory Birds of Provence, with Observations on the 

 Dates of their Migration. By M. J. Duval- Jouve, Professor of 

 Philosophy in the College of Grasse. 



It is probably a task of greater difficulty in Provence than in any 

 other part of Europe, to observe with precision the dates of the arri- 

 val and departure of birds of passage. This difficulty I conceive to 

 be in a great degree attributable to the geographical position and cha- 

 racter of the country. The interior is occupied by mountain ranges, 

 some of which are so lofty as to retain the snow on their northern ac- 

 clivities throughout the entire summer. The plains stretching towards 

 the sea are low, and consequently enjoy a much higher temperature, 

 so that on the approach of summer it is still cold on the mountains, 

 even when it has become very hot in the plains. Cold and wind have 

 great influence in retarding or accelerating migration : and it often 

 happens that those species which are descending towards our coast, 

 either from our own mountains, or the more northern provinces of 

 France, arrest their flight and stay for a longer or shorter time on the 

 hills of moderate height. In many instances food has a direct influ- 

 ence on migration : for instance, at Castellane, which is about thirty- 

 six miles from Grasse, there is not a single thrush to be seen through- 

 out the summer ; but at the end of September, when the juniper-berries 

 are ripe, the thrushes arrive in immense flocks, and remain there about 

 six weeks, or till the middle of October, when they descend to the le- 

 vel lands, which are thickly planted with olive-trees, whose fruit is 

 then ripe, and among these they remain until the olive -harvest is over 

 and the trees completely stripped. 



The autumnal migration extends over a considerable time. The 

 first heavy rains seem to arouse the migratory impulse, and to bring 

 the earliest travellers towards our shores, but it requires a greater de- 

 gree of cold to cause the main migration. Often after we have expe- 

 rienced severe cold, the weather again becomes mild, and the move- 

 ment then seems suspended for a while, indeed, until wintry weather 

 again sets in, and compels the travellers to resume their journey. I 

 have observed that sometimes when the early autumnal rains have 

 fallen in sufficient quantity thoroughly to cool the earth and atmos- 

 phere, and when a light wind has blown from the north-west, the birds 

 of passage have arrived in immense flocks, and the sportsmen have 

 made great havoc among them : but this is not the case when the 

 north-west winds have not been preceded by rain. When the autum- 

 nal rains are late, this general early movement does not take place, 

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