"Do you want to go first and get it over with, or wait to see how it's done?" Mick asks Lorna. She looks grim. "Is that my only choice?" she says.

You can hardly blame her. We've been in our kayaks for only a few minutes and already we're faced with a set of rapids that Mick, our guide, cheerfully tells us is called "Boat Crusher". When we signed on for a couple of days canoeing down the Northern Territory's Katherine River, we thought meeting the occasional crocodile would be our biggest challenge: white water didn't enter the picture.

As we bumped and lurched in the 4WD across the tropical savannah to the launching site, however, Mick's partner Jen explained that because the stretch of river we'll be paddling along has no suitable nesting sites for saltwater crocodiles and therefore no females, the only crocs we may see would be juveniles "and even then not if they see you first". A dozen gaudy kayaks will be too scary a prospect for a teenage saltie - and the more common smaller, freshwater crocodiles are even shyer.

It's a weight off my mind, to be honest, especially as sleeping on the river bank just metres from the water is part of the plan.

But now there's this to worry about. Mick is standing in the river downstream, instructing us on how to tackle the current swirling through the jumble of rocks ahead and repeating that if we tangle with a boulder we should embrace the experience - literally. "Lean into the rock," he shouts, "and hang on to it. If you try to push away you'll be in the water, guaranteed." Lorna selflessly demonstrates this, and Mick fishes her out with one hand, catching her kayak with the other. She's none the worse for it - the water's shallow and warm, the day hot - and as Jen sends us through one by one, the rest of us somehow bumble through with no casualties. I glimpse a dead kangaroo on the bank as I zip past and someone asks afterwards who else smelt it. "All I could smell was my fear," says Michael, straightening his helmet.

At the next set of rapids Lorna gets spun around and comes through tail-first, nerve-jangled but dry, and Mick nods: "Some people manage better backwards." But by the third stretch she's got it sorted and skims through like a pro, paddle held high like the rest of us, enjoying it now for the burst of speed and the excitement, making it a game not to touch any rocks or flood-deposited logs.

Not that the long calm sections are dull: it's wonderfully peaceful and relaxing to go with the flow, floating along under the silver-tipped and weeping paperbarks, watching dazzling rainbow bee-eaters perform aerobatics as they chase insects, and listening to kookaburra laughter echo through the treetops. I spot an azure kingfisher shimmering over the water, a great-billed heron chuckling to itself on a dead branch and a white-bellied sea-eagle swooping overhead mobbed by a flock of protesting ravens and galahs. Motionless on a low branch is a baby freshie, just 40cm long and hoping not to be noticed; Jen is standing in her canoe and spies others in the water, plus river rays, barramundi and turtles - but no salties.

I see a golden tree snake cut across my bow and slither up the bank; and ahead of me, Rebel glimpses a dingo that's been chasing a couple of wallabies through the bushes. When we reach the sandy beach that's to be our camp for the night, there are animal tracks everywhere, and I take care to arrange my swag so other bodies are between me and any night-time bush-whacking animals. But, in the end, they're the last thing on my mind when I wriggle into bed.

Mick and Jen have served us roast beef at a long table with cloth and candles, and we've chatted for hours as the three-quarter moon rose, spotlighting the flood debris caught in the fork of a tree 10 metres above our heads. We've sat by the driftwood campfire afterwards with hot chocolate and TimTams, toasting our toes as the sand cooled; and then we've drifted away to our swags to tuck ourselves up and lie watching for shooting stars and satellites.

Tomorrow there will be more rapids to make us grin, hot springs to bathe in while little fish nibble our feet, and ancient rocks to sit on at lunchtime while pied butcherbirds serenade us with their melodious song. But for now there's just the river rushing past, the stars wheeling overhead, and nothing to do but sleep.

Mick is based in Katherine and offers a range of river trips:

Knot's Crossing Resort
has a range of accommodation in Katherine; or Coodardie Station, 120km beyond Katherine, provides accommodation on a working Brahman stud farm.

For more information, go to www.tourismnt.com.au.
Pamela Wade was a guest of Tourism Northern Territory.