Chook migration routes are already examined by several different procedures including the oldest, marking. Swans are marked by using a nick over the beak given that about 1560 in England. Scientific ringing was pioneered by Hans Christian Cornelius Mortensen in 1899. A lot of substantial birds (like eagles and vultures) https://kingbookmark.com/story20429219/the-greatest-guide-to-why-petsky-store