The captain of a fishing trawler is bemused by Moko's attraction to his vessel, after the dolphin rejoined his boat in the Bay of Plenty.
Moko is now basking in Tauranga Harbour, after following the trawler Eskdale into dock from a fishing expedition near White Island.
The Eskdale's skipper, known only as Sprat, said he could not explain why the large bottlenose had chosen his boat in a heavily used shipping lane, and stayed with it for days at a time.
"It could be the music," he said. "We play a bit of AC/DC as we travel and he seems to like that."
At Christmas the Eskdale lured Moko away from Gisborne, where he had resided for several years since leaving his home beach in Mahia.
After the crew swam with him in the Gisborne harbour, the dolphin travelled more than 400km in the boat's wake to Whakatane.
"He seems to like the boat's stabiliser. He hangs around, rubbing himself against it, and swimming in the warm water which the boat discharges."
He said Moko may have warmed to their gentle treatment, referring to a number of incidents in Gisborne where the dolphin was given rough handling by eager onlookers.
"We're not whacking it with an oar or anything, he's well looked after here."
A former minder for Moko said he was attracted to the bright colours of fishing boats, and was probably drawn to the orange buoys which the Eskdale trailed behind it.
A Gisborne businessman, who owns a game fishing boat and hosts sightseeing tours, has offered the Eskdale's skipper $3000 to lure Moko back to Gisborne's waters.
Sprat said he wouldn't consider it.
"It's too far to go, and we like his company. The crew don't wanna lose him."