Helen van Berkel discovers a precious natural highway, not far from the roar of Auckland traffic.

It doesn't look like a battleground. The Okura River estuary looks just like one of the many tidal creeks wriggling deep into Auckland's insides from the coast. On the other side of the great, grey-green river is the grey-green canopy of the Okura Bush Scenic Reserve and between us and the grey-green waters of Long Bay Regional Park is a bare green peninsula farm.

But it is a battlefield: this is the northern edge of Auckland's urban area, also known as the green belt. This is the bulging seam holding back Auckland's house-hungry hordes who are eyeing this pretty coast as their future neighbourhood.

The civilian casualties in this battle are summertime godwits -- currently in Alaska for the northern summer -- and the stilts and the oystercatchers and dotterels balanced on rocky reefs, mostly submerged now in the high tide.

The birds noisily chide us as we approach but subside to chat among themselves when they realise our goal is the upriver mangroves.


As we head into skies darkening with an approaching westerly storm, the birdsong continues: I won't pretend I recognise them all but I think there are tui, piwakawaka (fantail) and kereru (woodpigeon) and perhaps kotare (kingfisher). The estuary teems with mullet, flounder and stingrays, and locals tell me dolphin and even orca have been seen here. But the most exciting fish I see is the one I didn't: something jumps out of the water with a good-sized splash just beyond the reach of my paddle.

My usual kayaking mate was unavailable, so my companions on this late-autumn Sunday afternoon are Peter and half a dozen others on a have-a-go-at kayaking fun day. An unexpected bonus was that Peter provided the kayaks, which meant no hosing-down nonsense stood between me and a hot shower when I got home.

The only noise as we paddle west is that of the birds and the soft splashing of our paddles. Along the shore, small jetties extend into the creek. Kayaks and dinghies are pulled up on grassy banks and muddy beaches. Sometimes the creek widens into a smooth bay, the water, sometimes grey, sometimes brown, reflecting the mangroves and trees on the shore. Our prows slice almost silently through the still water, unzipping our westerly path. Then the banks close in and mangroves brush against our craft. The gushing sound is a skinny ponytail of a waterfall, dropping several metres over a rocky cliff. The further west we go the louder the traffic sounds become. East Coast Rd and the Northern Motorway thrust great concrete legs into this creek, arteries for car-bound Aucklanders clattering home from their weekend homes in the north.

It's appealingly mysterious down here in the shadows; mere metres from a road that is often bumper-to-bumper with commuter traffic in the mornings, cars rumbling by overhead, their occupants having no idea that we're here. The roadways overhead are vital arteries for the swollen body that is Auckland, and so is this little creek, probably the last untouched still lovely estuary close to suburbia on this coast, its cleansing tides bringing food and nutrients to creatures we don't see and of whose presence we are mostly unaware.

The tide turns as we near the end of the navigable waterway. Fallen trees block the way and knotty lumps of sunken pines pose a hazard. Peter says he'd like to see these trees removed. Why, I wonder aloud, isn't their decay just a part of the cycle of life and death?

No, he points out: these are non-native pines and not a natural part of this habitat.

We turn and glide back on the ebbing tide. The trip back is far faster than the upstream journey and hauling my kayak ashore at the boat ramp, I'm surprised to see two hours have effortlessly slid by.

The oystercatchers and dotterels, standing on rocky reefs that have now widened to broad shelves, ignore us, focused instead on the tasty goodies the tide has deposited at their feet, and grateful to have their estuary to themselves once more.

Need to know

• To find out more about Okura tours see online here.

• To find out more about protecting this coastline see here.