The Bottlenose Dolphin which is commonly found in Plettenberg Bay sometimes shows curiosity towards humans. Occasionally, they can be found rescuing injured divers by raising them to the surface. They also do this to help injured members of their own species. In November 2004, a report of dolphin intervention came from New Zealand. Four lifeguards, swimming 100 meters (328 ft) off the coast near Whangarei, were approached by Great White shark the dolphins herded the swimmers together and surrounded them for forty minutes, preventing the shark from attacking, as they slowly swam to shore.
Researchers of the Bottlenose Dolphin Research Institute first quantified data about solitary bottlenose dolphin diving behavior in the presence and absence of boats. Dolphins responded more to tourist than fishing vessels. Driving behavior, speed, engine type and separation distance all affect dolphin safety.