Bird migration routes are already studied by a range of approaches such as the oldest, marking. Swans have already been marked using a nick around the beak due to the fact about 1560 in England. Scientific ringing was pioneered by Hans Christian Cornelius Mortensen in 1899. About us: For everyone https://petskyonline-onlinestrore.blogspot.com/2025/07/rethinking-animal-store-why-petsky-is.html