If possible, leave found young birds where they were found
The Environmental Agency informs
Spring is also the time when the offspring of many bird species leave the protective nest. Here, outside the nest, they are fed by the adult birds for several weeks and only gradually become independent.
During these weeks, concerned citizens repeatedly ask the nature conservation authority what should be done with young birds that have been found. Without a parent bird nearby, young birds often give the impression that they need human help to survive. Most of the time, however, the adults are simply foraging at the time of observation. Feeding intervals vary depending on the species. For example, the intervals between feedings are quite long for bird species with a crop, such as birds of prey and pigeons. You should therefore first observe from a reasonable distance and unnoticed by the adult birds for a longer period of time whether the young are really no longer being fed. In principle, they should be left where they are found.
If no feeding is detected during uninterrupted observation for about an hour, it is permitted to temporarily take the young bird into care if there is sufficient expertise, time and accommodation available, without contravening the applicable nature conservation regulations. Further information can be found at www.wildvogelhilfe.de.
In cases where the young birds are obviously in danger, e.g. if they are sitting at the side of the road, you should deviate from this principle and place the bird in a protected place such as a hedge or tree. However, the young birds must not be moved too far away from where they were found so that the adults can still hear the begging sounds of their offspring. In contrast to other young wild animals such as deer, hares or rabbits, birds can be safely picked up in such situations. Human odour is meaningless to the adult birds.