Auckland conservationists are waiting to hear what action the government will take to protect the North Island Hectorâs dolphin. The population of the small, playful mammal, regarded as the worldâs rarest dolphin, is down to about 100 â most of which swim and ride the swells in inshore waters from Manukau Harbour to Raglan Harbour. Conservationists blame more than a century of set netting for the decline of the dolphin. This year, two Hectorâs dolphins were washed up near Kariotahi, south of Manukau Harbour. Modelling of the population has calculated that the North Island Hectorâs dolphin could become extinct if more than one dolphin is netted in a five-year period. The Waitakere branch of the Royal Forest and Bird Protection Society is concerned that measures proposed to protect the dolphin will not go far enough and supports a West Coast marine mammal sanctuary for the dolphins.