Those damn endangered Hawaiian green sea turtles! Can't they read? Or at least listen to the pre-snorkel briefing?
You must have heard the breakfast announcements? As we were sailing out to Molokini Island, off the south-eastern tip of Maui, the team in charge of our Trilogy catamaran had been insistent.
These are rare creatures, they'd explained. They're shy. They need to be left alone. Feel honoured if you see one. But keep your distance. Humans aren't allowed within 10 metres of them.
Our family had taken that on board as we jumped off board. We adjusted our masks and began snorkelling into the almost-perfect crescent that is Molokini. We didn't see a single green sea turtle at Molokini, and felt quite proud of ourselves for not disturbing its natural habitat.
But then, after lunch, our catamaran sailed close to Makena Bay. After five minutes in the water, we had seen a green sea turtle. Look, there it is, my 14 year-old son had said.
Indeed, there it was – metaphorically anchored on the bottom, some 10 metres below a gaggle of humans as if reinforcing its knowledge of turtle legislation.
So, having glimpsed the turtle, I swam on. But a couple of minutes later my other 12-year old son began slapping flipper. "Dad, you're missing it," he said. "We're swimming with the turtle!"
Should I reprimand him for an over-fertile turtle imagination? Or reprimand him for transgressing the 10 metre rule?
But when we swam back, I couldn't believe what I was experiencing. If this Hawaiian green sea turtle was shy, so was Miley Cyrus.
The turtle was swimming on the surface in a crowd of snorkel-wearing strangers, seemingly oblivious to any ecological announcements or prescribed distances.
After perhaps five minutes on the ocean surface, the turtle plunged a metre or two beneath the waves and started flipping her way westwards towards the breaking waves.
We followed a discreet way behind for 10 minutes, knowing this was one of the great aquatic safari experiences of our lives.
She showed no sign of discomfort, disquiet or despair. Quite the contrary, we humans felt she was luring us – like the Sirens of Greek mythology – on to rocks. Sure enough, one of the Trilogy guides interrupted our reverie, pointing out we were getting dangerously close to where the relentless Pacific surf was about to pound into coral shore of Makena Bay.
But back to Molokini. From the air, the crater is one of the most spectacular spots on earth – an almost perfectly formed hemisphere, a crescent-shaped volcanic moon in a deep blue ocean, an unoccupied Santorini of the Pacific.
Today Molokini is recognised as one of Hawaii's most popular scuba diving and snorkelling venues. But it wasn't always so. In World War II, the US Navy bombarded Molokini with heavy artillery because – apparently – the island resembles a non-moving Japanese battleship.
For a decade after 1975, the navy carried out a program of detonating any unexploded munitions it found within the crater, devastating large areas of coral before it was stopped by public outcry.
Thankfully, these days, concern for Molokini's environment is more alert. To be honest, too many cruise boats are still allowed to moor in the crater in the peak morning hours when the waves are shallower and the snorkelling easier.
But at least each tour boat has its own fixed mooring (rather than dropping an anchor which would cause new damage to the coral).
And none of us is allowed to touch Molokini from the water, let alone step upon it. It is now an official Hawaiian seabird sanctuary with at least two species nesting on the island – Bulwer's petrels and wedge-tailed shearwaters.
Really, though, it is the aquatic life (rather than the seabirds who feed off it) which draws international visitors here to Molokini.
The crater is said to be home to 250 species of fish.
What do we see? The most common species, of course. They include black triggerfish, yellow tang, Moorish idol, parrotfish, butterflyfish and bluefin trevally.
With so many tour operators in Maui offering essentially the same trip to Molokini and the Green Turtle Coast, how do you choose the right one?
Ultimately it comes down to a few crass questions.
How much do you want to spend on a day trip? Which ports are most convenient? (Ours went from Ma'alaea harbour, near Lahaina.)
What sailings best suit you, morning or afternoon? And how much extra are you happy to invest for safety, a reasonably stable crossing to and from Molokini, the thrill of being on a sailboat rather than a "stink boat".
You know the clincher that persuaded us to choose Trilogy over the cheaper alternatives?
The quality of the buffet... But then swimming after turtles is hungry work.
Hawaiian Airlines flies daily from Sydney and four times weekly from Brisbane direct to Honolulu, using new Airbus A330-200 aircraft. Connections from Melbourne and other Australian cities available with preferred partner Virgin Australia.
Hawaiian Airlines also has around daily Boeing 717 flights between Honolulu and Kahului airport, Maui.
Sail Trilogy is considered one of Hawaii's premium snorkelling and scuba experiences. See sailtrilogy.com
Steve Meacham travelled at his own expense.
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