To some people, crabs are ugly, aggressive scavengers that nip the toes of unsuspecting bathers in cartoons. To biologist John Walsby they are beautiful, complex creatures whose lives are full of intruiging secrets.

Imagine an underground reservoir so large that it has its own tides. A spring of such clarity that the term "crystal clear" is actual, not imaginary. Where distance is deceptive, and divers in its waters seem to hang suspended, as if in space.

What an improbable animal is the seahorse! With a horse's head, a possum's tail, eyes like tiny glass fishbowls and fins that wave like chiffon frills, the shy creatures have intrigued and delighted us since ancient times. But these thoroughbreds of the sea are now in danger of their lives. Ground up for medicines, sold, sightless and stiff, as souvenirs, captured alive for home aquariums, seahorses in many parts of the world have a hard ride ahead of them. A combination of public awareness and aquacultural research - some of it being conducted in this country - may yet turn the tide for these fascinating animals.

Placid or storm-tossed, the surface of the sea is merely the portal into Earth´s largest domain, the ocean realm. For 15 years, Tauranga-based marine biologist and photographer Kim Westerskov has dived his home waters of the Bay of Plenty and found myriad subjects for his camera.

Two-thirds of the Earth’s surface is covered by ocean, with an average depth of nearly four kilometers – making deep-ocean seafloor the commonest environment on our planet. Through our vast extended economic zone, New Zealand controls a disproportionately large slice of that mysterious terrain. What is down there? Scientists from National Institute of Water and Atmospheric Research have the job of finding out. In September 2001, they took their equipment – including a bottom lander, here being hoisted over the side of the research vessel Tangaroa – to the Chatham Rise, one of our most important deep-sea fishing areas.

Holding your breath: It’s as simple as that, and as hard. Try it now as you read. Take a quick deep breath… hold… and read on. Right now you are trying to assess how much air you’ve managed to cram into your lungs. You’re facing the sure knowledge that very shortly, probably inside a minute, you will experience an overwhelming urge to breathe, to open your gullet and suck in great life-sustaining drafts of fresh air. How will you cope with that moment when it arrives?

The forests of the sea can grow up to half a metre a day, but as we now know, they can also teach us about Earth’s ancient climate.

Photographer Darryl Torckler travels the length of the country, revelling in the underwater riches of New Zealand’s marine environment.

Enter the dark realm of New Zealand’s largest freshwater resident, the longfin eel—a monster that has become the stuff of countless myths and legends.

A self-taught diver who was never daunted by a challenge but took it on with a mixture of enthusiasm, determination and improvisation.