DOC Marine Species Technical Advisor Kristina Hillock says the two dolphins were spotted by a member of the public on Thursday 19 October, near Te Kouma's Sugarloaf Wharf. Te Kouma is a few kilometres south of Coromandel Town.
It's just the third time in 60 years the species has been spotted in the Firth of Thames – and Kristina says the two dolphins may be the same animals seen off East Cape a week ago.
"We occasionally get reports of Hector's dolphins on the east coast of the North Island, such as around Hawke's Bay and the eastern side of Coromandel Peninsula – but their usual habitat is around the South Island," Kristina says.
"That makes the sighting of this pair particularly important to us: If we can relocate the dolphins, we'll try to get a small skin sample from them for scientific purposes."
The skin sample would provide genetic information that would help determine which subspecies the animals came from.
Anyone who sees the Hector's dolphin can report it directly to 0800 DOC HOT.
"If you do spot the dolphins please maintain a respectful distance, but do record the date, time, GPS coordinates (if available), the time spent near the dolphins, the direction the animals are moving, and descriptions of the location and activity of the dolphins," Kristina says.
Videos and photos of the animals are also beneficial for DOC's marine scientists, as imagery or footage helps confirm the species and any identifying marks on individual animals.
A small group of Hector's dolphins were spotted off the coast of Coromandel's Hot Water Beach in 2020. In September and October 2022 there were several sightings of a Hector's dolphin between Mahurangi Harbour and Mangōnui (Doubtless Bay), but DOC staff weren't able to get a skin sample from this dolphin.
Hector's dolphins are recognisable through their distinctive rounded dorsal fin, shaped like Mickey Mouse's ear. They are grey and white with black markings.
Hector's dolphins are classified as 'nationally vulnerable', with an estimated population of 15,700 individuals.
Māui dolphins are classified as 'nationally critical' with an estimated 54 animals aged one year or more within the survey area on the west coast of the North Island.
Although it's possible the dolphins spotted in the Firth of Thames are from the Māui subspecies, it is considered unlikely.