The Hapai Te Hauroa Maori Public Health posted on its Facebook page: "It is with great sadness that we note the passing of Dr Apirana Mahuika.
"Dr Mahuika of Ngati Porou was a leading force in Maori and iwi development over many years and several of us had the privilege to have crossed paths with him."
Dr Mahuika was honoured by Police Commissioner Mike Bush in October for the "significant work he has undertaken to ensure NZ Police upholds their commitment to Maori and the Treaty".
He was chairman of the Te Kotahi Research Institute at the University of Waikato, and was an ordained Anglican Minister for more than 50 years.
In 2012 the Royal Society of New Zealand described him as a "leading figure in most of the major political and topical issues that have confronted iwi in recent years".
"His passion for the promotion and protection of Ngati Porou Taonga and Te Reo ake o Ngati Porou is unrelenting and he is committed to the self-determination of Ngati Porou whanau/hapu and to education and the pursuit of excellence in all endeavours."
Former National MP Tau Henare also tweeted a tribute to Dr Mahuika, describing him as "more than a kauri".
"His passing will cut a swathe through the forest," he said.
Dr Mahuika had died early this morning, Mr Henare said.
Others on Twitter described the Maori leader as "one of the greats".
The late Sir Paul Holmes named his son with ex-wife Hinemoa Elder after Dr Mahuika following a helicopter crash in 1989 on the East Coast which took the life of TVNZ cameraman Joe Von Dinklage.
Sir Paul was quoted as saying he would always do right by Maori after the crash, in gratitude for the care he and his fellow survivors received after swimming to shore.
He gave Reuben the name Reuben Thomas Apirana Holmes, after Dr Mahuika, who was known as 'Api'.
"It was deeply emotional and spiritual. We were gathered in the Shanks' house when we got in from the sea," Sir Paul said in an interview with The Listener in 2012.
"Rana [Waitai] arrived in his police commander's car with Api, and Api said, 'Shall we say a prayer?' because Joe was missing.
"Well, I've never forgotten it. That's why Reuben's got his name."
New Zealand First Leader Winston Peters said Dr Mahuika was a leader who stood out.
"He had the ability to cross all divides and had a special ability to draw people together.
"He was a man of strong faith, a tremendous advocate for his iwi and a man of vision who could inspire those around him.
"In a real sense this is the end of a great era."
Green party co-leader Metiria Turei said Dr Mahuika was a formidable leader, who was always very gracious.
"He was strong and stubborn but always respectful. He challenged my views and I challenged him back."
Dr Mahuika was a bastion of Ngati Porou leadership, and a Treaty of Waitangi scholar.
He was open to embracing new and innovative ideas - including green ideas - if they were for the betterment of his people, she said.
Labour leader Andrew Little said Dr Mahuika was a born leader, not only as the head of Ngati Porou, but as an ordained Anglican minister for more than 50 years, and was also a teacher and scholar.
"Uncle Api, as he was affectionately known, worked tirelessly to improve the lives of his people through education and his drive for self-determination and self-reliance for Ngati Porou.
"He also worked hard for all New Zealanders though his work as chair of the Iwi Leadership Forum and the positions he held on at Waikato University's Climate Change and Te Kotahi Research Institute and on many other boards.
Labour's MP for Ikaroa-Rawhiti, Meka Whaitiri, said Ngati Porou had lost a great leader.
"His passion and commitment will be remembered not only by his whanau but by all of Maoridom."
Police Commissioner Mike Bush said the police had lost "a truly honourable friend, mentor and great leader".
"Words cannot express our sincerity for a man who gave so much to make this country a safe place for all New Zealanders and the love that he had for his people.
"Uncle Api, as he was affectionately known to New Zealand Police, was a long serving member of the Commissioner's Maori Focus Forum. He was instrumental in strengthening New Zealand Police's relationship with Maori, and was one of the key architects of our Responsiveness to Maori programme.
"In 1996, Uncle Api gifted New Zealand Police a whakatauki, which was designed to reflect the belief that together, Maori offending and victimisation could be reduced. The words of the whakatauki were subsequently brought to life through the Police tohu.
"Late last year I was privileged to be able to present Uncle Api with a green stone carving of this whakatauki, recognising him for the significant work he had undertaken to ensure that we uphold our commitment to the Treaty and to Maori."
Mr Bush said he was honoured to represent New Zealand police and previous Police Commissioners in thanking him for laying down the wero, sharing his knowledge and advancing New Zealand Police's thinking when working with Maori communities.
"Uncle Api started the journey for our organisation and continued to guide us through unchartered waters in the development of a world class model of partnership between Maori and New Zealand Police.
"His mana and wairua will live on. "
Treaty Negotiations Minister Chris Finlayson said Dr Mahuika was a fantastic person and he was really saddened he had gone.
"I loved the guy like a father," he said.
"He was an utter force for good for Ngati Porou."
He was a staunch Ngati Porou man; it meant everything to him, Mr Finlayson said.
When he appointed Dr Mahuika to the Historic Places Trust, he had told the minister that Friday meetings would not suit him because he regularly went to the District Court for sentencings on Friday for young Ngati Porou men who got into trouble.
Mr Finlayson said he had planned to visit him at home in mid-January before leaving for Europe but Dr Mahuika had been too unwell.
Education Minister Heki Parata said Dr Mahuika had devoted his life to fostering, strengthening and supporting the development aspirations of Maori and he took a particular interest in education.
He had recognized the transformative effect it could have on lives from pre-school right to post graduate study.
"In doing so, he followed in the footsteps of his namesake Sir Apirana Ngata."
She said she great heart from the fact that the subject for his masters' thesis was the influence of women leaders in Ngati Porou - Ms Parata's own iwi.
Maori Party co-leader and Maori Development Minister Te Ururoa Flavell said Te Tairawhiti and te ao Maori "have lost a great leader of our time."
"Dr Api Mahuika exuded rangatiratanga. He was unrelenting in his promotion and protection of all Ngati Porou taonga - from its fisheries, foreshore and whenua to Ngati Porou reo and tikanga."
He was at the vanguard of early Treaty claims and settements including the Maori fisheries settlement, the landmark Wai 262 claim and the Ngati Porou land claim, Mr Flavell said.
During his long tenure as chairman of Te Runanga o Ngati Porou, the iwi authority increased its asset base, established social services such as Ngati Porou Hauora and formed the first iwi education partnership "Whaia te Iti Kahurangi" with the Crown.
His oratory skills in te reo Maori and English are legendary, said Mr Flavell.
Co-leader Marama Fox said Dr Mahuika's ability to articulate his views and immense knowledge on the marae and in hui would be greatly missed.
"He was a scholar and a gentleman."
