Introduced by Leslie Clague
This is the second instalment in the serialisation of Jim Hilton’s talk to the Nelson Science Society, and covers scientific approaches, and the role of the browsing Moa in the evolution of New Zealand’s biodiversity.
(For the first instalment see http://kapitiindependentnews.net.nz/will-poisons-save-new-zealands-biodiversity-part-1/ )
Science ethics and information overload
By Jim Hilton
The Royal Society of New Zealand has a code of ethics which covers issues of professional integrity. It spells out that scientists should represent themselves as experts only in their field of competence and that credit must be given for others ‘ ideas and contributions’. It advises that statements made to the public must be done without distortion or unjustified extrapolation.
My scientific training is in Biology, Geology and Chemistry. More specifically my training focused on animal and plant ecology, animal and plant behaviour and population ecology. The ideas I present tonight are not new. I have stolen them from all over the place.
“Information overload” is a huge problem for scientists. Reading scientific papers and publications, then sorting them out, is a nightmare for me personally. When I do finally stop reading and make a sensible conclusion? Fortunately many experts in their fields start writing books as they get toward the end of their careers, summarising their ideas and condensing the “Information overload” into something more digestible. I’ve been reading these sorts of books for years.
I’m sure one of the main reasons mankind has got itself into trouble with poisons, is because science today looks at things in smaller and smaller detail.
I’m not the first person to conclude that if we keep examining things in minute detail, eventually we will know everything about nothing. I like to step back and look at the big pictures. Otherwise we will never see the “wood (forest) for the trees.”
New Zealand comes out of the sea
About 35 million years ago New Zealand sank below the ocean, becoming a chain of islands, the largest of which was present day Central Otago. But a fresh period of mountain building started and our present day Southern Alps gradually rose from the sea.
That’s a good place to start the New Zealand biodiversity story, because a lot of the South Island was later covered in ice. Many of our unique plants and birds were lucky to survive at all. It was at the time (when NZ was a chain of islands) that our giant Moa split into nine different species, a species on each island.
The amazing range of New Zealand Moa
Understanding the role of Moa and our other browsing birds is crucial to understanding why we have NO need to poison our introduced wildlife. As New Zealand rose from the sea, it took on its present shape and the different species of moa fitted into the habitats for which they were best suited.
The largest species was the Giant Moa, the tallest bird that ever lived. It was at least three metres tall at full stretch and weighed on average 167 kg. The smallest species was the Little Bush Moa weighing in at 15 kg. It was about the size of a goose. The Heavy Footed Moa weighed in at 200 kg. They were swamp dwellers with short stumpy legs.
The Upland Moa was a specialist high country browser, well adapted to living around the snowline with feathers right down to its ankles. It weighed in at 30 kg. The Crested Moa was the rarest. It, too, was an alpine species. Its stronghold was northwest Nelson.
Estimates of the numbers of Moa in New Zealand when the Maori discovered the land about 800 years ago have varied from five to 12 million. Recent studies, however, suggest it was more like one million. They were certainly very common though and the main diet of Maori for the 13th and 14th centuries.
Part 3 of this series will look at Moa hunting and the experience in other countries with native fauna extinctions.