Now, the signature whistle is a whistle that's specific to an individual dolphin, and it's like a name.  And this is the best-studied sound, because it's easy to measure, really,
Fluieratul-semnatură e un fel de fluierat specific unui anumit delfin, un fel de nume al acestuia.  Acesta e cel mai studiat sunet, fiind foarte ușor de măsurat.