DNA may show moa on way out before hunting

A New Zealand moa specialist plans to spend more than $800,000 on a study of North Canterbury moa fossils, which he says will show whether the birds were in decline before Maori began hunting them to extinction.

Richard Holdaway's study will use DNA technology to work out whether the moa population that existed before human settlement was stable, national science academy the Royal Society said in a statement announcing the Marsden Fund grant.

Before Maori arrived, it is thought the only predators killing moa were powerful yet nimble Haast eagles.

The eagles were able to kill the moa they caught with a single strike to the head or neck, but died out within a few hundred years of Maori arriving, and some historians have pointed to their main food supply, moa, being eradicated by Maori hunters.

Dr Holdaway, a palaeobiologist, plans to use genetics, biochemistry and physics to discover secrets of both the moa and their environment.

A team led by Dr Holdaway, of Palaecol Research Ltd, will try to find out what North Canterbury moa ate, whether their diet changed with age, whether they lived in family groups and how large their populations were.

Radiocarbon dating will be used to try to determine the ages of some bones at two major deposits in North Canterbury.

Ancient DNA data will help identify the species of the moa bones, their sex, estimates of population sizes, and family relationships.

Stable isotope analysis will provide insights into what the birds ate, and from what area.

The two deposits of moa bones were found at the Pyramid Valley swamp in 1939 and 65 years later, 5km away, beneath Bell Hill Vineyard.

These two swamps trapped birds of all ages, and included at least four species of moa from a period extending back 4000 years.

DNA research has already shown that there were two species of giant moa in New Zealand, and that the females were nearly twice as large as the males.

- NZPA