The Lac Du Der has become one of the most important roosting sites in Western Europe for the Common Crane during the migration periods. In November and in februari-march, up to 70.000 Common Cranes come to sleep at this huge artificial lake, which serves as a drinking water reservoir for the Isle de Paris. During the previous decades, the number of wintering birds kept on increasing. Nowadays the site holds also important numbers of wintering Cranes. Up to 10.000 Common Cranes are feeding during most of the winter in the fields and meadows around the lake.
On the last day of our journey at the lake, we witnessed a wonderfull wildlife spectacle: thousands of Cranes came to sleep to the lake, while the sun was going under. On the contrary to the previous days, when most of the birds only flew in after sunset, the birds were earlier this day. Moreover, the sunset was amazingly spectacular and the sky first colored bright orange, and later on went red and purple. The sight of the purple sky with flying cranes and the sound of thousands of trumpetting birds made our journey unforgettable.