Lihou Reef, we’ve finally arrived. Crystal-clear water was only a footstep away. We donned masks and fins, and instantly free fell into another dimension, a salubrious drug of choice that became our habit for the next four weeks.

Pic shows us anchored behind Turtle Islet at the NE end of the atoll.

We were now inside a vast elliptical string of reefs that stretched over 60nm long and 20nm wide. Five vegetated cays, 15 sand cays, and a deep lagoon were waiting for us to explore. It is one of the world’s biggest and least visited atolls, just 360 nautical miles east of Cairns. Almost untouched, being a protected national park since 1982. I had re-powered our 14M Powercat Flash Dancer, so no more procrastination, late spring 2022 was a perfect time to visit. We travelled to Lihou from Townsville, then had stopovers at the Diamonds and Herald cays on our way back to Cairns. A six-week 940 nautical mile sojourn.

Our initial R&R was behind Hermit Crab Islet. Marine birds of every description covered the island, and easy dingey access was a bonus. It is a well-sheltered anchorage in solid trade winds. Later, we found Diana, Edna and Lorna cays also work well. Observation Cay was our sweet spot during blustery North easterlies.

This rough map is derived from our C Maps helm chart. It shows approx locations of the vegetated cays and a few of the sand cays we visited. The Light yellow is the best area for great lagoon diving peaks.


Unfortunately, there are no beautiful coral gardens around the anchorages. It’s pretty much all bare coral rock. But it’s a different story in the centre of the lagoon, where many peaks rise sharply to the surface. Soft and hard corals, covered walls, and nutritious algae combined with 50-65 m depth attracted exciting pelagic action.

On nearly every dive, there was a period where activity seemed to be everywhere. Visibility was always at least 30 m, up to 50 m. My most vivid memory was our first lagoon dive, where a wall dropped 30 m before gradually reaching the bottom. It seemed I could see forever. We floated in space, surrounded by schools of curious fish; on the periphery were more than 20 curious sharks, plus dog tooth, tuna, mackerel, barracuda, and more. A three-meter silvertip shark with an entourage of hundreds of rainbow runners was spectacular.

I love to see life through my camera lens, but on many occasions at Lihou, life was too big – an epic panorama. I often left the camera and just floated with the seascape in awe. We had magical scenes similar to this at 9 of the 12 Lagoon peaks we dived. Forget the cute creatures, sea snakes and Nemo; this is spectacular, big-view pelagic territory.

Inside the lagoon, this peak had a nice smattering of coral at 20-30m

Our hydrographic C-MAP charts of Lihou were excellent, so there were no nasty surprises, and finding pics marked on the charts as either rock near the surface or coral patches is fine. But anchoring to dive with no dinghy backup person on board takes a little thought. The possibility of swift currents that move up, down and around the lagoon has to be considered. We have found that anticipating where the title stream is draining and flooding around coral sea reefs is complex and can vary markedly from day to day. Sometimes it’s possible to anchor close by and utilise the dinghy. Other times, having a lightweight, manoeuvrable boat is handy and becomes our dinghy. Whichever way you look at it, diving in these places is always an adventure. Fortunately, my first mate is an excellent dive manager. On top, she feeds out a 25-meter safety rope: underneath, she is in control and an excellent navigator. By diving on small peaks at slack water, we could lap around the rise and still have plenty of exit time for decompression and any possible scenarios.

Looking up at our anchored vessel is always interesting, especially when many sharks are underneath.

We love our Underwater photography, but cameras make good sea anchors, so when conditions are problematic, we leave them behind.

Lihou Reef Marine birds

Above the water it’s the birds who dominate the scene. Their prolificness, especially on the grassed islands during the spring nesting period, is astonishing. Are there enough little fish and squid to sustain them? It seems so. Brown Boobies are the most eye-catching, and, Noddies are everywhere. At times flocks of Sooty Terns cover the sky. My favourite terns are the shy little Black Naped Terns whose white plumage stands out against the aqua seascape. There is also a smattering of Frigates and a few minor species, and we noticed a Pelican that must have lost its bearings.

Black Naped Terns

After a while, you start to identify with much of their behaviour. Mum and dad take care of the kids, and then there is the training on how to fly and hunt, the rescues, and the parental stress when they get into trouble. Any parent would relate to all the happenings.

Some species have little or no fear of humans, while others are skittish. At least out here, there are no aggressive seagulls to steal their eggs. All the same, we took great care to keep our human disturbance to a minimum.

Boobies are coming to visit us as the sun rises over one of the cays.

While sitting at the water’s edge one day, we watched a mother noddy return from the ocean. She identified her chick among hundreds of look-alikes with a couple of verbal exchanges. The longer we stay in these places, the more we notice and empathise.

Chicks are waiting for a feed. Wheres mum?

Lihou Reef Turtle time

Turtle tracks and potholes cover every beach. Spring is that mating and nesting time. They take their time with both and are very successful. Observation cay was the only place we saw a significant death rate. Its vast bear expense must occasionally cause disorientation, and about 20 had died from heat exhaustion over recent years before returning to the sea.

A deceased turtle at Observation Cay. A nesting masked booby is in the background.

We love to see turtles when we’re diving. Resting on the bottom, often, curious — we could be a prospective mate! Or we could be some kind of a shark, so they hi-tail it at surprising speed, with powerful legs flapping like giant petrel fins.

Lorna Cay

Lorna was one of our most enjoyable places. It was easy to zip back into the lagoon peaks for diving, and we especially liked the extensive sand areas at both ends making for easy dinghy access. One glassy calm day, I sat on the edge of the little shallow bay which had formed at the north end at low tide. Right before me, multiple turtles were being romantic; tawny sharks were cruising amongst schools of baitfish, and a few naughty chicks wandered down from the vegetated area to sit in my shade along with the usual hermits. A magical time. I dozed off in my nature dream time until the tide came in, and an inconsiderate wave washed me back to my dinghy.

Back on the boat, I felt this day was too good to end. We had parked on the Ocean side of the reef at 18 m depth, close to where it begins to descend to 600 m. I thought it was a good place for a night dive. Then I was reminded about the Tiger sharks. We hadn’t seen any, but they were here, waiting for a slow, flapping mammal resembling a sick, dying turtle to feed on! Thanks first mate, for pointing that out! With a strobe burning brightly for comfort, I jumped in. No tiger sharks, just a harmless, White tip shark checking on its territory. Soon I was surrounded by Trevalley and Red Bass, very excited about the tiny shrimp I was stirring up. A couple of Butterfly fish and many multiple feather stars brightened the scene. I like night diving.

White Tip reef shark
Night dive happenings

Queen Christina ship wreck.

The 100 m-long steamship sits conveniently on the top of a reef. Although it dates back to 1899, it’s still an excellent snorkel at low tide. Its anchor and prop are intact, and quite a few reef fish make it their home. Worth a visit.

Lihou Lighthouse

It’s one of the furthest offshore lighthouses in the world, and at 33m high, it is an impressive structure. We climbed six ladders to get to where we reached a sign saying to keep clear. To late, we were there and enjoying a fantastic view of the reef below.

We have visitors.

We didn’t expect to see another boat, but after three weeks of solitude, we were interrupted in the most friendly way by John from the national parks. And right behind us was the MV infamous. It was choc full of bales of flotsam and volunteers collecting rubbish from remote locations and erecting signs.

A recently published Coral Sea cruising guide and the feasibility of more boats appreciating Australia’s remote coral sea territories is improving. With the possibility of increased traffic, national park authorities stressed the importance of visitors taking precautions not to transfer seeds or insects from one location to another inadvertently. Part of our own biosecurity edict is to minimise wander time spent on the more vulnerable vegetated cays. Plus, after each visit, we swim and use our outside shower to wash further and soak clothing and shoes.

A big thanks to Marine Parks for erecting new signs (SW Cay) and picking rubbish like this drift net. (Although the hermit crabs liked the shade)

A sandy picnic.

That heavenly picnic on an ocean beach is not out of the question — there are many tiny sand cays with no vegetation and very little birdlife to disturb. But you won’t be alone. The sand is moving; Hermits are on the crawl, and many more enjoy a siesta in the shade of a coral rock or some washed-up debris. Around the edges, Pale-lined rock crabs scamper everywhere, Ghost crabs pop out of the sand with their big claws, and then the Red-eyed reef crabs scurry to the nearest ledge. Low tide around the rock pools is also a busy time for feisty, small grey eels. Watching one pursue a small fish trapped in a rock pool was an action-packed event. I was barracking for fishy, but the eel wasn’t about to give up and eventually won the day.

Ghost Hermit Red Eye

Fiesty Grey Eel Ocean Beach Picnic

After four weeks, it was time to head back home to Cairns. But first, we utilised the incredible underwater visibility for a morning of underwater portraiture. My first mate donned her worst dress, favourite hat and sunnies, and we were happy kids playing in the park.

My favourite portrait
Thanks for checking out our web site. Cheers Rob and Syl

Suggested further Coral Sea information……

  • Coral Sea Marine parks – for gov info you need click here
  • Australia’s Coral Islands & Marine Park cruising guide book by Peter Sayer-the only complete guide.
  • To check out more of our destination stories about Coral Sea reefs and atolls, click below.

Diamond Islets click here

Ashmore Reef click here

Herald cays click here

Marion Reef click here

Willis Islets click here

Coringa Islets click here

Osprey Reef click here

Bougainville Atoll click here

Magdelaine Cays click here

Flinders Reefs click below

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  1. Bill Gardyne on 5 June 2023 at 12:01 pm

    Thanks Syl and Rob, your blogs are always lovely to read and your photos utterly spectacular.

    I have Lihou on my bucket list for later in the year. Hopefully the wind and cyclone gods will be kind.

    • Robin Jeffries on 8 July 2023 at 9:05 am

      Hi Bill, I hope the weather is kind to you. Cheers Rob

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