Temptation islands: Wild encounters you can only have in this part of the world

The dogs surge up the trail towards the sound of tumbling water. In each hand I grasp a leash connected to a panting, wagging bundle of furry joy. At the waterfall we unclip the leashes and the dogs plunge into the jade-hued swimming hole, paddling and grinning as they cool off. Few can resist joining them for a dip. Swimming with wildlife in the Cook Islands usually involves turtles, rays, whales and other marine creatures. But today we're splashing with a less exotic species: homeless pups from the SPCA shelter on Rarotonga, the largest of 15 islands in an archipelago scattered like emeralds over two million square kilometres of blissful blue Pacific Polynesian Triangle.

For a donation of $NZ25 ($23), visitors can enjoy the SPCA's Waggy Tail Walking Experience on Rarotonga's south shore, here at Wigmore's Waterfall or on a pristine beach nearby. It's an unfailing mood lifter where everyone wins: the dogs revel in affection and exercise, and the humans - well, same.

"What these dogs crave most is human contact," says Dave Pokia, SPCA president, as his charges sprawl at our feet. "They always enjoy a walk, but some visitors give them a brush, have a play or a chat."

He currently has 40 residents; a jigsaw of breeds so mixed you can only guess at their ancestry. Quite a few have distinctively short legs, a feature attributed by local legend to a prolific visiting corgi rumoured to have royal connections.

Each dog costs about $NZ4 a day to feed, and as the SPCA relies solely on sponsors and donations, the tourist walks provide a lifeline. Funds also support the SPCA's free desexing program - essential for maintaining a canine population the small island can support. The homeless pups are in great hands with Dave and his dedicated volunteers, but it's still a poignant situation for a pup in a place where a dog's life on the outside is so utopian.

On Rarotonga, fringed with 32 kilometres of pristine beaches and encircled by a turquoise reef lagoon with balmy shallows, pets wander as freely as the humans who come to cast away their cares. Hens, cats and dogs roam white sands and tropical gardens, and snooze in the sunshine's soothing embrace.

On the beach at boutique Nautilus Resort, where you can grab a free kayak or SUP for a paddle on the lagoon, friendly pups have been known to hitch an occasional lift on a board. As I sip a pina colada at the Nautilus poolside bar, with a pooch dozing at my feet, I wonder if there's any better recipe for relaxation: barefoot luxury, endless blue, plus unofficial therapy dogs.

Later, I'm seeking the company of a different species, where the Avaavaroa Passage flows through the lagoon and a gap in the reef out to the deep ocean. It's home to Rarotonga's largest population of sea turtles and eagle rays.

The passage's powerful, conveyor-belt current demands experienced guides - and ours pack extra propulsion. On the beach, Ariki Adventures team introduces us to a gadget straight from James Bond's toolkit: a sea scooter. This battery-powered, hand-held contraption resembles an outsized hairdryer and moves you through the water faster, enabling maximum turtle viewing and safer swimming through those potent rips. I'm feeling major Aquaman energy as we power out towards the reef.

Our guides lead us to an underwater neighbourhood where several gigantic turtles recline on rocks while little fish clean their shells. A turtle spa, says Cody, our guide, as we gaze in frank awe at a grande dame the size of a coffee table. She's estimated to be close to 90 years old.

These turtles are all female. Are the males hanging out somewhere in a turtle man cave? Sadly not, says the Ariki team. Nearly all green turtles are born female, outnumbering males by about 116 to one. Warmer ocean temperatures produce more female babies, and you don't need to be David Attenborough to grasp the reproductive implications of global warming for this vulnerable species. During our 90-minute swim, graceful turtles weave among us. As one approaches, I back up, conscious of the strict no touching rule. She follows, and her dark, unfathomable gaze holds mine for a long, magical moment before she glides away. I've had an audience with a queen.

Unforgettable animal encounters are everywhere in the Cook Islands. On neighbouring island Aitutaki, we snorkel and swim amid a dreamlike lagoon vista where sea and sky seem as one, and gleaming white swathes of untouched sandbar punctuate the endless wash of blue.

Beneath the palms on Aitutaki's tiny motu Maina, I discover red-tailed tropic birds nesting on the ground beside fluffy white chicks who resemble snowballs with faces. In the water, I'm circled by a stately Napoleon wrasse about a metre long - another marine monarch. Neither creature is afraid; here in the gentle, laid-back Cooks, there's little reason to fear humans.

When it's time to depart, we await our flight at the beachfront Islander Hotel bar, opposite Rarotonga airport, enjoying a last look at the ocean. As if on cue, a humpback whale breaches right outside. There could be no better farewell flourish.

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Getting there: From March 27, Jetstar is launching a fourth weekly service between Sydney and Rarotonga, with one-way fares from $249.

Staying there: On Rarotonga, Nautilus Resort (nautilusresortrarotonga.com) has luxury villas (sleeps three) from $NZ882 ($808) a night. On Aitutaki, beachfront adults-only Etu Moana's (etumoana.com) villas boast stunning garden and lagoon views and start at $NZ680 a night, breakfast included.

Touring there: SPCA Waggy Walks are daily at 9am, $NZ25. See cispca.yourholiday.me. A 90-minute Turtle Sea Scooter Safari with Ariki Adventures is $NZ189 per person, with five per cent donated to the Cook Islands Sea Turtle Conservation Society. See arikiexperience.com/turtle-sea-scooter-safari

Explore more: cookislands.travel

The writer was a guest of Jetstar and Cook Islands Tourism.