Diamond islets — Coral Sea — posted March 2016

diamond islets centralWho wouldn’t like to cruise to a group of deserted Coral Sea Islands without leaving the comfort of Australian waters? In the spring of 2013 we Diamond islets Cruise mapspent 18 days on our 14m cat visiting the four pristine Diamond Islets, located 500 kilometres north east of Townsville. Below is our account that was published in Australian Multihull world.


South Diamond Islet

Right on cue, the ocean’s deep blue expanse gave way to a mix of brilliant sapphire colours that surrounded a sandy beached pimple, its scraggy green top was swarming with thousands of sea birds. After leaving the outer reef we had sat on seven knots for 23 hours, and it was exhilarating to finally arrive at South Diamond Islet. Four Green Turtles were just laying placidly on the beach, with small waves washing over them. Our anchorage was tolerable in moderate seas about 250m from the cay; the ocean floor below was half sand / half coral heads, rising from ten me to within three me from the surface. Our vessel was safe. The water was crystal clear, although the coral was in poor condition because of storm damage sustained from cyclone Yasi in 2011.

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We dropped the anchor on a sandy patch amongst coral heads and kept the chain short–that is the only way to anchor around the Diamonds.

Observing our surrounds, it became apparent we were in the middle of a turtle mating area, as several groups were copulating close by. We jumped in for a snorkel and witnessed a female with four males queuing up to service her. One impatient male was trying to dislodge the active male by biting at his fins. Later we realised this biting behaviour was common and seeing males with bites out of their back fins was not unusual. Being a romantic, my partner decided to make our first objective to observe and photograph mating turtles. We were lucky and found some midnight lovers on the beach and shot some interesting video of a couple mating on the ocean floor.

Females sometimes swim to the beach for a rest, especialy when groups of males are fighting for mating rights .

Females sometimes swim to the beach for a rest, especially when several males are fighting for mating rights.

Our first beach landing was interesting—we headed to the cay armed with our best cameras, and high expectations of capturing images of birds, as well as nesting turtles, silhouetted in a red sunset. It was high tide, and the ocean swell was wrapping itself around the beach making for a tricky surf landing. No problems for this boy – this was right in my wheelhouse — run up on the back of a wave, cut motor, leap out and get the dingy as far up the beach as possible…OOOPS…SLIGHT MISS CALCULATION… a very large wave snuck up while I was in la-la land; too late to follow this one in. I gunned it, and the last thing I remember was pointing vertically down at the beach! WIPE OUT! Somehow the dinghy finished right side up; First mate was under it, and I was laying next to a spinning prop. Must remember to attach the cut out cord to my wrist next trip in! Rubber duck had somehow finished right side up. Our cameras floating in their large water tight bag; how fortunate we were. First mate thought it all very funny; I was too busy wiping the egg of my face to laugh!


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Quite a few turtles die when they become caught up or just exhausted amongst the rocky windward side of all these Islets.


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The eastern side of the cay’s water’s edge had nasty rock formations; a deadly trap for nesting turtles unlucky enough to get wedged among them. Several dead turtles were a testament to the hazard. I noticed one turtle had been washed head-first into a nasty crevice; it was alive and flapping in desperation; as the tide was soon to recede it had no hope of extraditing itself. As much as I hate to interfere with nature, I couldn’t just stand by, so I spent half an hour pushing and pulling and finally seeing it safely back in the sea. I hoped she would get her energy back and land on the beach next time. My little rescue mission felt good, although my aching back and bruised fingers never felt quite as excited.

Boobies are our favourite marine birds. Three types nest in big numbers on these islets.

Masked Boobies nest on the beaches.

Masks Boobies nest on the beaches.

Brown Booby-- they usualy make their nest amongst the vegetation away from the beach.

Brown Booby– they usually make their nest amongst the vegetation away from the beach.

Red footed like be of the ground and usually rest and nest on branches

Red-footed like be of the ground and usually perch and build their nest amongst branches.

East Diamond Islet

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Trying to catch a fish during our 35 kilometre trip to East Diamond Islet was more difficult than expected. Trolling three lures we were constantly hooking Grey Whaler reef sharks—it was such a pain getting the hooks out of their mouths—especially for them—I had to use my little bolt cutters and sacrifice my trebles several times. We eventually settled for a couple of Jobfish and a small Dog Tooth Tuna to supplement our provisions. They cooked up nicely on the BBQ.

A small Dogtooth Tuna.

             A small Dogtooth Tuna.

East Diamond is the pristine anchorage of the group: a spectacular bay offers excellent protection from south thru to north east winds, and a little shelter from northerly and south westerlies. The chart number AUS614 is detailed and is very accurate.

The Islet was superb for observing turtles and sea birds. Hundreds of turtles each night crawled up the beach to lay their eggs, and marine birds were everywhere. I have never seen so many Lesser frigate birds, about 2000, and

Frigate birds

                           Frigate birds

when hundreds decided to glide the up drafts to the stratosphere, it was an amazing sight to behold.
It’s possible to climb the navigation tower, and the bird’s-eye view gave us an excellent islet prospective.
The Cay had the full complement of marine bird species; our favourites were the petite white capped Black Noddies and Red Footed Booby birds that nest in the branches of shrubbery.
The juvenile Red Footed Boobies also loved to gather on our bow rails, and we often found ourselves standing next to them chatting away in birdy talk: it’s a bit like baby talk. They would come and go like teenagers meeting at the arcade; sometimes up to 40 visitors at once. Fortunately, our pets preferred spending their nights on the islet: so poop mess and smell were minimal.

Immature Red-footed Boobies battling for landing rights.

Immature Red-footed Boobies battling for landing rights.

A brown Booby flies past the Noddies . toward the immature Red-footed Birds

A Brown Booby flies past the Noddies. Toward the immature Red-footed Birds perched on  weather beaten shrubbery.

Soon after we arrived the winds dropped to five—ten knots and stayed that way for a week.The water visibility was an amazing 50 me at times.
We had a few scuba dives, mostly on a bommie that rose from 42 me, and was situated about 800 meters from the island. No schools of snapper or jacks here, but a good smattering of Chevron Barracuda, Grey Whaler, and White Tip reef sharks; big Dog Tooth Tuna could be seen circling. A superb swim through cave was home to some of the best Gorgonian Fan Coral I’ve seen, and I noticed a couple of Nudibranch. Not a bad spot, but unfortunately this was the only obvious deep water bommie about.
Snorkelling around the main reef was OK but not outstanding. Always plenty of Turtles. One male turtle was very enthusiastic about mating with me, and I ended up holding it away with my hand on his head; as if saying “pull your head in mate, wrong species!” Little reef sharks were numerous, but our favourite sharks were the docile curious Tawny Sharks. They were no doubt well fed from multitudes of local crustaceans, who would have to be the most successful animal group on the islets. The beach was covered with thousands of Hermit crabs and scampering about the water’s edge were a multitude Rock crabs.
I enjoyed playing cat and mouse with the spritely Pale Lined Rock crabs, trying to capture the perfect photo, which of course, I never got.

Pale-lined rock crab

                            Pale-lined rock crab

Land hermit crabs are very socialable.

                                               Land hermit crabs are very sociable.

Red Hermit Crab

                                 Red Hermit Crab

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                                                   Beautiful Gorgonian Fan Coral.

Shooting a tiny sea slug

                 Shooting a tiny sea slug



Chevron Barracuda

                  Chevron Barracuda

One beautiful quiet day we decided to try our hand at underwater portraiture. Sylvie put on a dress and sunnies and free dived; I sat on the bottom with my scuba tank taking shots till her little lungs complained. It was fun anyhow—we have potential.

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After an idyllic week, we moved ship west to explore the central and west islets. We returned when the winds turned North Westerly. A yacht stopping over on its way to Australia from Vanuatu was the only other visitor. It was pleasant to share stories with another human for a couple of days.

Central and West Diamond Islets

Birds at West Diamond Islet.

                                                                                     Birds at West Diamond Islet.

These two cays are very similar to South Diamond Islet, with an indentation on the NW side of the reefs allowing reasonable anchorage about 200—300 me out from their beaches; OK in light to moderate SE wind conditions. The beach landings gave us more choice opportunities for a wipe out with our dingy; I admit to having become very cautious by then.
The Islets were home to many thousands of marine birds. One young booby landed on my camera lens. Obviously, it had no knowledge of focal length what so ever!

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There were many hundreds of nesting turtles, and we noticed one had become haplessly jammed under a rock ledge, which had slid back on top of her as she filled in her nest. It looked as though she had been trapped there just the one night, so we judged that being out of the sun, she may have had enough strength left to get herself out if only we could just free her up! After three hours of digging, we were elated when she finally made her way back to the water. I doubt whether any humans set foot on these little islets from one year to the next, so this has to be the luckiest nesting turtle in the Coral Sea.

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Despite the Diamonds isolation, it was disappointing to see the rubbish around the shores. It had been carried by ocean currents from South East Asia. Just shows what washes out of one’s country’s drains can end up thousands of miles away, in someone else’s back yard.

We enjoyed a few days exploring, swimming, diving with the reef sharks and watching the turtles go by. The first mate had created the worlds most advanced banana and pumpkin cake, and with gusty northerly conditions threatening we decided on a retreat to the southern edge of East Diamond.

Back to East Diamond Islet.

We seemed to have temporarily gained a new pet, a small Tawny shark that swam around beside us while we snorkelled. I found an unusual Moray eel, and the first mate got to pick up more plastic rubbish from the islet. We dismantled a fishing net attached to a bamboo pole that probably had been washed down from the water people in Borneo or Philippines. The nesting turtles would have thanked us if they could.

Tawny shark

                        Tawny shark

Spotted Moray Eel

Spotted Moray Eel

We came across a badly mauled turtle on the beach. It looked like a Tiger Shark had grabbed hold of it, partly crushing it, and chewing off a front fin. I don’t think it would survive very long; that’s nature. It some what put us of our late afternoon snorkel, so we weren’t too upset about leaving the next day.

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All was good with our boat. We had ample fuel and food supplies, so with our enthusiasm still intact we headed in the direction of the Magdelaine Cays and the Willis Islets.

One of the best anchorages in the far eastern Coral Sea

East Diamond Islet chart complements of navionics. One of the best anchorages in the far eastern Coral Sea

We have wonderful memories of the 18 days we had exploring the 4 islets.

  The three smaller Islets are all within 20nm of pristine East Diamond Islet.Cart compliments of Navionics.

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Click here to view all out images of the Diamond Islets.

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