The Department of Conservation is investigating the cause of death of a suspected Māui's dolphin, found on a beach in western Waikato.
© DOCThe Department of Conservation is investigating the cause of death of a suspected Māui's dolphin, found on a beach in western Waikato.
A suspected Māui's dolphin has been found dead near Te Akau on the west coast, 20 kilometres north of Raglan.

A local man discovered the dolphin on the beach on Sunday and reported the sighting to DOC.

Two DOC rangers who responded to the report and assessed the site, took measurements and photos of the dolphin before removing it from the area.

Less than 100 of the critically endangered species are left and its death has been met with sadness by the Department of Conservation (DOC) staff and iwi.

DOC acting operations manager for Waikato, Lucy Roberts said the dolphin was a female and it was suspected it washed ashore with the incoming tide.

"It was in very good condition. There's nothing there that can give us any indication of the cause of death."

There have been five recorded Māui's dolphin deaths since 2008 with the last reported death occurring in Port Waikato in January of this year, attributed to shark predation.

Māui's dolphin are the rarest and smallest of the world's 32 dolphin species and have only been found on the West Coast of the North Island.

A recent estimate of the Māui's dolphin population indicated that there are 57-75 individuals over one year of age.

The dolphin has been sent to Massey University veterinary pathology specialists in Palmerston North so the cause of death can be determined. Roberts said it was expected this process would take five to seven days.

A tissue sample will also be sent to the University of Auckland for genetic analysis to determine sub-species identification. This would determine whether it was a Hector's or a Māui's dolphin, she said.

There are no indications yet to the cause of death, and DOC will await findings from Massey University.

Forest & Bird marine advocate Anton van Helden described the death as tragic.

"Any Māui's dolphin death is a considerable blow. The population so small that every individual matters."

The population currently stands at 63 animals over the age of one.

"We know that a population of this size can only sustain one death every seven years, to have any chance of recovery. There have now been two reported Māui's deaths in seven years.

"Raglan is a hotspot for Māui's dolphins - it's right in their range. This animal is highly likely to be a Māui's dolphin."

Iwi have requested return of the remains once necropsy testing has been completed.