This is very sad but it appears that poachers have killed several of the dolphins who protected swimmers from a great white. The Scotsman reports:
The mutilated carcasses of the two bottlenose dolphins were found on Wednesday in the Awaroa River, which branches off the upper reaches of Whangarei Harbour on North Island’s east coast.
Staff from New Zealand’s Department of Conservation (DOC) believe the dolphins died about two weeks ago after drowning in fishing nets set out by criminals poaching fish. DOC officer Richard Parrish said their tails had been hacked off, probably to free them from the net.