The young female bottlenose dolphin put Opononi on the map when she surfaced in the Hokianga Harbour in the autumn of 1955, reportedly after her mother died, and, over time, built confidence with the locals. By summer she was swimming with children, entertaining people with her capers and creating a media sensation.
Thousands of holiday-makers braved the Hokianga's metal roads to see her, her antics even including allowing children to sit briefly on her back. Opononi's hotel and camping ground were fully booked, and the town enjoyed a tourism and publicity boom that has never been matched.
Heightened interest brought its own issues, however. Opo was occasionally jabbed with oars, and there was the odd scuffle for her attention. Once somebody even took a pot-shot at her. Concerned locals formed the Opononi Gay Dolphin Protection Committee, and called on the government to protect her.
As a result, an order in council came into effect at midnight on March 8, 1956 making it an offence to take or molest any dolphin in the Hokianga Harbour, and carried a 50 ($100) fine. It didn't work.
"Sadly Opo was found dead the next day, jammed in a crevice between rocks," Brooke said. (One possibility is that she was killed by fishermen using gelignite).
"Her death drew messages of sympathy for the people of Opononi, including one from the Governor-General."
Writing in the July 1958 issue of 'Te Ao Hou,' Piwai Toi, one of the first people to see Opo close up, recorded his thoughts:
"Why did the dolphin come to live in the Hokianga River in the year 1955? She was seen following rowing boats during February of that year. On Easter Saturday in March 1955 a memorial for Kupe was unveiled, after whom this river was named the Hokianga, or 'Return of Kupe'. Mr Hohepa Heperi, a Maori elder who was brought up in the Hokianga, said to us: 'Opo is the fish of peace, a legacy from Kupe.'
"She died on some rocks above Koutu Point, about three miles up-river from Opononi. The Maori name for these rocks is Te Kauere o Kupe. It was towards the end of March 1956 that Opo died. These coincidences are certainly strange."
Opo was memorialised in a stone statue by Russell Clark, erected in 1960 down the road from her grave. After suffering vandalism, the statue was replaced with a bronze casting in 2013.