Video: Diver frees dolphin snared by fishing line The video shows a diver repeatedly attempting to free the dolphin from a fishing line tangled round its torso and flippers. Initially the man uses his hands to disentangle the dolphin, before resorting to a knife to cut the line. The dive operators who uploaded the video make clear that the man involved was an experienced diver with thousands of hours of experience, and that they "do not advocate attempts by lay person to rescue marine life."