Weekend leisure: Fossil hunting

The Takapuna reef fossil forest. Photo / Steven McNicholl

Dionne Christian and her family rummage around in nature's past on a fossil-hunting expedition.

My youngest daughter will one day be reminded of her first fossil hunt, thanks to how she described it to her grandmother: "I went to the beach to look for dinos, but I didn't find Rudy or Buck and a giant eagle ate my icecream."

Translated by her older sister: "We went to the fossil forest on Takapuna Beach but there were no dinosaur bones, especially not characters from the movie Ice Age 3 who aren't even true. We ate icecreams after, and she dropped hers on the sand, because she wouldn't stop running around, so a seagull ate it."

Given the association of fossils with dinosaurs, it was only natural that as soon as we told the kids we were going fossil hunting, they thought we'd be digging up brachiosaurus bones.

But the term fossil describes the preserved remains or traces of any animals, plants and other organisms from the very dim and distant past - we're talking millions, sometimes hundreds of millions, of years ago.

Fossil hunting brings us up close and personal with a time so remote many of us can barely begin to comprehend what the world would have looked like.

It's a great way to get outdoors for some exercise that doesn't feel like exercise and switch kids on to learning some basic scientific principles. Finding a fossil can lead to all sorts of questions related to biology, climate and environmental change, geology, geography and so on.

So we found ourselves on Takapuna Beach at low tide, picking our way across clumps of pock-marked black boulders and splashing in rock pools. Takapuna Beach (along with Ihumatao in south Auckland) is home to one of the best examples of prehistoric forest remains preserved in an ancient lava flow.

"Now imagine," said the girls' fossil-hound father, "that there are lots of trees growing here and that it's not a beach but a forest and suddenly red-hot lava is flowing all around the trees because just over there - what is now Lake Pupuke - was a volcano, which blew up. These rocks are the leftover remains of the lava where it oozed around trees and burnt them down. It left holes - like tree footprints."

A visit might not be the equal of finding a tooth from a T-Rex, but it certainly caught the imagination of Miss Nearly Seven.

Her dad was around the same age when he bought two fossilised fish at a South Auckland Rock and Mineral Club show in the Old Papatoetoe Town Hall. They're skeletal remains, preserved in sandstone - amazingly well given they're several millions of years old. He still has them on display in the living room.

We've reignited his interest in fossil hunting thanks to James Crampton's and Marianna Terezow's informative and well-illustrated The Kiwi Fossil Hunter's Handbook, a Fathers' Day gift.

Aimed at families and novice fossil hunters, the book is a comprehensive and accessible beginners' guide, which covers what fossils are, how they're formed, where and how to find them in New Zealand and the best sites around the country for budding fossil-hunters. It also includes a "fossil collecting code" which talks about the right way to go about such endeavours.

Inspired by the book and our afternoon at Takapuna Beach, the next step was to go fossil hunting in our own backyard.

We have a stream at the bottom of the garden and while we didn't have any idea if it's in an area likely to yield fossils, we took the kids down for a look.

We didn't find anything - fossil hunting can be a slow process - but I was delighted to learn that the stream is one of the few in Auckland where we might just have stumbled across a fossilised mollusc from the Miocene (around 20 million years ago). A few years ago, a group of palaeontologists unearthed "several hundred" fossils in the area.

While Auckland isn't the greatest place to find fossils because the rocks are volcanic or deep water sediment with very sparse fossil remains, there are a number of recommended sites in The Kiwi Fossil Hunters Handbook.

These would make good day or weekend trips: Mathesons Bay near Leigh, Puti Point on the north shore of Kawhia harbour and Mangapohue in the King Country, among others.

NEED TO KNOW

Want to find out more about fossil hunting? Then you might like to contact:

* The Auckland Geology Club

* North Shore Rockhounds Club

* South Auckland Rock and Mineral Club and the Papakura Lapidary Club. Ph (09) 276-7456