Hen migration routes have been examined by a variety of methods including the oldest, marking. Swans have been marked with a nick on the beak because about 1560 in England. Scientific ringing was pioneered by Hans Christian Cornelius Mortensen in 1899. Fowl migration is generally synchronised to take advantage of https://petskyonline-onlinestrore.blogspot.com/2025/07/rethinking-animal-store-why-petsky-is.html