NEW ZEALAND: Researchers probe past with pooh

Scientists have won funding to study the fossilised stools of birds including the extinct moa, in a bid to find out what impact the giant bird and its avian peers had on New Zealand's forests.

Moa, a group of flightless birds reaching as much as 3.5 metres in height and hundreds of kilograms in weight, dominated New Zealand's forests and grasslands until the arrival of humans. But exactly what impact they had on that vegetation is unknown as moa have been extinct since about 1500 CE.

Dr Jamie Wood and Dr Janet Wilmshurst from Crown research institute Landcare Research, along with Professor Alan Cooper and Trevor Worthy at the University of Adelaide in Australia, hope to shed light on that issue.

They will examine a large collection of 1,500 coprolites (fossilised faeces) from moa and other birds whose species of origin are currently unknown. First, Wood will extract and analyse DNA to determine which bird species deposited each coprolite.

The preserved dung will then be examined for seeds and leaf fragments to see what plants the birds ate. This analysis will indicate not just diet, but also ecological zone, sex, and even season.

The team will also study soil from relatively unmodified forests across New Zealand, to examine how forest understorey composition has changed over the last 1,000 years. This will span the periods with moa, without any large herbivores at all, and with introduced herbivores such as deer and goats.

The study was recently awarded NZ$768,000 (US$522,000) over three years by the New Zealand government's Marsden Fund for basic research.

John.Gerritsen@uw-news.com