A distressed bottlenose dolphin stranded for a second time on the Tūtūkākā Coast has been euthanised.

The Department of Conservation (DoC) received a call about a dolphin beached on the Ngunguru Sandspit near Whangārei last night. Project Jonah also sent three local volunteer marine mammal medics.

They worked with local hapū Ngāti Taka, Ngāti Korora and Te Waiariki at sunset to refloat the dolphin, believed to be around 3 metres long and weighing 300kg-400kg.

Hopes were high as rescuers watched the fully grown dolphin swim out to sea.

However, DoC spokeswoman Abigail Monteith said the dolphin was found stranded this morning but with no obvious signs of injuries.

Multiple attempts to refloat the dolphin were unsuccessful, she said.

Iwi, marine experts, and DoC decided the “most compassionate course of action” for the dolphin’s welfare was euthanasia.

“The dolphin displayed signs of distress after the refloating efforts and persistently returned to the shoreline.”

Monteith said hapū performed a karakia and the dolphin would be buried on-site.

“DoC would like to thank local hapu Ngāti Taka, Ngāti Korora and Te Waiariki, Project Jonah and Massey University.”

Anyone concerned about marine mammals in distress should immediately call 0800 DOC HOT (Department of Conservation) or 0800 4 WHALE (Project Jonah).