Moa fed on nectar-rich flowers from flax and tree fuchsia, according to scientists analysing fossilised moa dung near Karamea.
Landcare Research scientists have just completed a detailed analysis of 35 samples of fossilised dung (coprolites) from a remote and difficult to access cave in the sub-alpine environment.
Until now, not much has been known about what moa ate in those areas.
The researchers, led by Dr Jamie Wood, descended steep bluffs to reach a high altitude cave in the Kahurangi National Park.
In the cave's entrance they found the coprolites - some still sitting on top of the rocks where they had been deposited centuries ago.
"Radiocarbon dating revealed they were deposited as long ago as 7000 years, making them the oldest moa coprolites yet discovered," said Professor Alan Cooper of the University of Adelaide.
The researchers identified at least 67 plant species from them, including the first evidence that moa fed on the nectar-rich flowers from flax and tree fuchsia.
The presence of intact seeds suggested moa were an important seed disperser for a range of alpine plants.
Dr Janet Wilmshurst of Landcare Research said the research had implications for understanding the ultimate demise of moa.
"It has always been a bit of a mystery how moa could have been exterminated so quickly from the remote mountainous parts of New Zealand. The abundance of pollen in the coprolites from spring and summer flowering plants suggests that moa were only up there during warmer months and may have come down to lower altitudes in winter where they could have been easier game for hunters," Dr Wilmshurst said.
The results of their study have been published in the international journal PLoS ONE.
- The Greymouth Star