Last Chance to See

gibber some more. The blades of the helicopter rotor are spinning mere inches from a tower of ice.
    She sighs. “Well, it will probably edit up into something,” she says and turns the tape off again.
    We take one more mind-wrenching turn around the giantice sculptures and then head off down the ravines once more, which now seem almost domestic by comparison.
    There is one other passenger in the aircraft: Don Merton, a benign man with the air of a vicar apologising for something. He sits quietly, occasionally pushing his spectacles back up the bridge of his nose and murmuring, “Yes, ah yes,” to himself, as if this all confirmed something he’d always rather suspected. In fact, he knows the area very well. He works for the New Zealand Department of Conservation and has probably done more than any man living to preserve the threatened birds of New Zealand.
    We are once again very close to the rock wall of the ravine, with hundreds of feet of sheer drop beneath us, and I notice that we are following a long narrow path that runs along an impossibly narrow ledge inclining gradually upward toward a spur overlooking a broader sweep of valley. I suffer from terrible vertigo. Being six foot five means I sometimes get giddy just standing up, and the very sight of the path gives me black swimmy nightmares.
    “We used to come up that quite a lot,” murmurs Don, leaning forward to point at it.
    I look at him in astonishment and then back at the terrifying path. We are hovering now just feet from it and the dull thudding of the rotor blades is reverberating back at us. The pathway is just a foot or two wide, grassy and slippery.
    “Yes, I suppose it is a bit steep,” says Don with a gentle laugh, as if that was the only reason they didn’t do it by bicycle. “There’s a track and bowl system up on top of that ridge ahead of us. Want to take a look?”
    We nod nervously and Bill flies on.
    I had often heard the term
track and bowl system
bandied about by New Zealand zoologists, and they had bandied it about so casually that I hadn’t wanted to say that I hadn’t the faintest idea what they were talking about. I decided to start from the premise that it had something to do with satellite dishes and work it out gradually from there. This led tomy being in a state of complete incomprehension for about two days before I finally plucked up the courage to admit my ignorance.
    A track and bowl system is nothing whatever to do with satellite dishes. It does, however, share with them this feature—that it is likely to be found in high, open places. It’s a rather odd name for an extremely odd phenomenon. A track and bowl system doesn’t look particularly dramatic, and indeed if you were not a New Zealand zoologist, you might pass one by without even noticing it, but it is the site of one of the most peculiar pieces of behaviour performed by any animal on earth.
    The helicopter sweeps out beyond the ridge into the open valley, turns and approaches the ridge again from the other side, lifts on the updraught, turns slightly again—and settles. We have landed.
    We sit in stunned silence for a moment, scarcely believing what we have just landed on. The ridge is only a few yards wide. It plunges for hundreds of feet on either side, and falls away rapidly in front of us as well.
    Bill turns and grins at us. “No worries,” he says, which I thought they only said in Australia. This is the kind of thought you need to distract you at moments like this.
    Nervously we climb out and, tucking our heads under the turning blades, scramble out onto the ridge. Spread out around our promontory is a deep, jagged valley plunging away from us on three sides, softening in its contours at its lower levels. Just beyond us it makes a sharp left turn and proceeds by a series of sharp twists and folds to the Tasman Sea, which is a hazy glimmer in the far distance. The few clouds, which are not that far above us, trace the undulations of the valley with their crisp shadows as they make their way slowly along it, and this alone gives us a clear sense of scale and perspective.
    When the thudding blades of the helicopter are finally still, the spacious murmur of the valley gradually rises to fill thesilence: the low thunder of cataracts, the distant hiss of the sea, the rustling of the breeze in the scrubby grass, the keas explaining who they are to one another. There is one sound, however, that we know we are not going to hear—not just because we