Questions were asked of the organisation after it was revealed that Ngai Tahu was in negotiations with Rotorua's Agrodome, with the possibility of purchasing the tourist attraction.
Neither organisation wished to talk about the project until negotiations were complete.
In May, the first sod was turned on a $10 million upgrade of Rainbow Springs Kiwi Wildlife Park, which Ngai Tahu Tourism took full ownership of in the 1990s.
The iwi plans to open a new water ride; teach visitors about the ecological evolution of New Zealand; create an interactive children's playground; and open an auditorium for hosting free-flight bird displays at the Rainbow Springs venue early next year.
The South Island iwi also owns and operates Franz Josef Glacier Guides and Glacier Hot Pools, the Hollyford Track (Southern Alps), Dart River Jet Safaris (Queenstown), Shotover Jet (Queenstown), and Abel Tasman Kayaks and Aqua Taxi in the Abel Tasman National Park. However, Te Arawa kaumatua and Tiki Tere Trust chief executive Jim Gray said he was concerned that if Te Arawa did not do something soon the iwi would miss the boat in terms of tourism investment.
"All Ngai Tahu have to do now is buy the Lakeland Queen, Skyline Skyrides or Hell's Gate and they would own all of the major tourist attractions in town with no likelihood for Te Arawa to buy them back," Mr Gray said.
Mr Waaka said the group should be looking to think outside the square.
"Maybe the Agrodome was not up for sale and Ngai Tahu made them an offer they could not refuse?
"But it worries me that our city is dying, there are many shops closed and no new ones going in.
"Te Arawa could re-inject some life into our city," Mr Waaka said.
Te Arawa Group Holdings chief executive Roger Pikia said the iwi had about $36 million in assets and had produced a long-term investment strategy governed by best practice and due care.
"We are in our second year of operation. Our priority remains in building a robust business that has the systems, capability and processes in place to maximise opportunity and value for our shareholders.
"The group will consider investment opportunities on a case-by-case basis, and make decisions based on sound financial information, and, that fit within the group's investment strategy.
"The priority will always be around ensuring best practice in all facets of our operation in line with the very clear expectations of our shareholders."
He said independent group director Wally Stone, who as former chairman of Ngai Tahu Group Holdings, was pivotal in the tribe's commercial success. Mr Stone is also former chairman of Tourism New Zealand and is present chairman of Whale Watch Kaikoura.
The group had identified key investment in a range of areas including geothermal, agribusiness, forestry, tourism and property.
"Our focus will always be on appropriate investment that seeks to grow our assets and value for this and future generations," Mr Pikia said.