Dear colleagues, We are preparing a review paper, including new records, on bending dorsal fins in free-ranging cetaceans, which is poorly documented. Being sure of similar events recorded worlwide, we invite you to collaborate in this study, offering co-authorship. If you have such type of data and would like to joint this study please send email to: filipe.alves@ciimarmadeira.org Thanks in advance, Cheers, Filipe Alves Marine biologist, PhD CIIMAR-Madeira Oceanic Observatorium of Madeira - ARDITI CV and publications: http://home.ciimarmadeira.org/index.php?page=filipealves