LAUSR

returned to the project. All Proyecto Eremita birds are fitted with unique coded darvic rings. Only the observation in  was confirmed to be an adult. Most birds making the crossing seem likely to be hand-reared juveniles. The birds that crossed towards Morocco in early November  did not, however, coincide with a disappearance from Proyecto Eremita. In  a total of  northern bald ibises were observed crossing or part-crossing the Gibraltar Straits in nine separate observations. Many of these sightings undoubtedly involved the same birds passing, but  birds (observations on three separate dates) were observed crossing to the south. It is possible that at least some of the birds returned to Spain undetected during this period. A minimum of  birds were seen crossing to Morocco on  September , and it is possible that the six observed on  November were surviving birds from that larger group, attempting the crossing back to Spain (having already set off north from Morocco). The Proyecto Eremita reintroduced population has now successfully bred  free-flying ibises, and  pairs bred in the wild in  with no significant intervention. These birds remain largely sedentary (regularly moving up to  km but rarely more than this). Austrian work to establish free-flying ibises reported multiple long-distance movements (several hundred km) of mainly juveniles, and only by enclosing the birds each autumn did they remain in the area (Fritz et al., , International Book Yearbook, , –), and enclosure in autumn is also used at Proyecto Eremita. Whether this population will develop a regular dispersion or migration pattern to the south remains unclear, and the continued monitoring and marking of the free-flying Proyecto Eremita juveniles is important, to differentiate between these and the possibility of sightings involving the slowly increasing, fully wild Moroccan birds dispersing to the north. We thanks the full Migres Foundation team, and specifically Andrés de la Cruz, Carlos Torralvo, Erin Arnold and Alberto Lobo for their observations.