This video says about itself:
An escaped Sacred Ibis on the Apaj Fishponds in the Kiskunsagi National Park, Hungary. The ring on the left leg is blue FW and on the right leg is IBIS ZOOSB 21. Is there anybody who missed this bird?
updated: the bird was escaped from Salzburg Zoo!
See also this report.
Due to escapes from zoos, the sacred ibis is spreading in western Europe now.
Update 2013: here.
Wintering birds in the Oudeland van Strijen: here.