Last Tuesday, a small crowd gathered on the road between Überlingen and Sipplingen on the shore of Lake Constance. With their heads far back, the visitors leaned against the crash barriers and watched the spectacle above their heads: at a height of 23 meters, Anne-Gabriela Schmalstieg presses herself deep into a large rock niche in the sandstone. Her yellow T-shirt can be clearly seen from below and identifies her as the foster mother of the ibises, who are picking at mealworms next to her, unimpressed by the dizzying height. They have not yet recognized their offspring, who are crouching close together in the wooden boxes, next to Anne.
For the Molasse rocks, there is concrete evidence of historical Northern Bald Ibis occurrences and even today, with their natural niches, they still offer the best conditions for nest-building. To establish the colony, human-led migrations started here every year between 2017 and 2019, in which a total of 88 young birds were brought to Tuscany and released. Anne-Gabriele Schmalstieg and Corinna Esterer were their foster parents at the time and are now working as bird managers to look after the colony.
This year, in the second year of breeding activities, the colony near Überlingen consists of seven nests with 17 young birds growing up in an artificial breeding wall. The colonization of the Molasse rocks as a natural breeding structure was initiated on Tuesday. For this purpose, three nests with a total of eight young birds were transferred to a suitable rock niche about 600 meters below the breeding wall. The chicks, now about three weeks old, were lifted into the rock niche with a lifting platform and placed in three prepared nests. Afterwards, the six parent birds were let out of the boxes next to their chicks. But the parent birds initially showed no interaction with their offspring. They only ate the mealworms offered and then flew back to the artificial breeding wall. Even after four attempts, none of the three parent pairs accepted the chicks at the new nest location until the evening, but the first interactions could already be observed. After a mild night, which the eight chicks spent alone in the rock niche, the first success was finally achieved on Wednesday after further attempts. Around noon, a pair of parents returned to the niche on their own after a short flight around, and a little later they could be observed feeding their chicks there for the first time.