• Home
    • Algae
    • Corals
    • Everything Else
    • Eels
    • Kingston, Norfolk Island
    • Nudibranchs, Sea Slugs and Flatworms
    • Octopuses
    • Out On A Swim Index
    • Reef Fish
    • Sharks
    • Sea Anemones
    • Sea Stars
    • Sea Urchins and Sea Cucumbers
    • Turtles
    • Underwater
    • Videos
  • Out on a swim - blog
  • About
  • Contact + Subscribe
Menu

Norfolk Island's Reef

Discover a fragile paradise – Norfolk Island's beaches, lagoons and coral reef
  • Home
  • Explore
    • Algae
    • Corals
    • Everything Else
    • Eels
    • Kingston, Norfolk Island
    • Nudibranchs, Sea Slugs and Flatworms
    • Octopuses
    • Out On A Swim Index
    • Reef Fish
    • Sharks
    • Sea Anemones
    • Sea Stars
    • Sea Urchins and Sea Cucumbers
    • Turtles
    • Underwater
    • Videos
  • Out on a swim - blog
  • About
  • Contact + Subscribe

Out on A Swim

‘Out on a swim’ is a coral reef blog that tells the stories of the characters who live under the waves and what has caught my eye when ‘out on a swim’ in the lagoons of Norfolk Island. It is also a record of the difficulties Norfolk Island’s reef faces, like many others around the world, as a result of the poor water quality that has been allowed to flow onto it.

This page shows the most recent blog posts. For the complete catalogue, visit the ‘Out on a swim index’ page.

This blog is rated in the Top 20 Coral Reef Blogs in the world.

Eclipse butterflyfish – Chaetodon bennetti, Norfolk Island

Celebrating Biodiversity Month on Norfolk Island

September 7, 2025

September is Biodiversity Month – the perfect time to celebrate the astonishing variety of life on Norfolk Island’s reef. From new fish sightings to coral mosaics, every observation is a reminder of how much there is still to learn and protect.

Read more about why biodiversity matters, globally and right here in our lagoon.

Read More
In Biodiversity Tags biodiversity, Fish, corals, Norfolk Island, Emily Bay, Slaughter Bay
Comment

Mr Lemonhead, the yellow boxfish (Ostracion cubicus) 8 August 2025, Norfolk Island

Biomimicry: How a Boxfish Caught Mercedes Benz’s Eye

August 10, 2025

Meet Mr Lemonhead – our lagoon’s teeny yellow boxfish with a big design legacy. He inspired a Mercedes Benz concept car, proving how nature is full of surprises. And he shares the lagoon with other critters whose tricks have also shaped real-world inventions.

Read More
In Fish Tags Fish, fish species, Norfolk Island, Mercedes Benz, biomimicry, design
Comment

Hynophora pilosa colony, Norfolk Island

Warning signs: what Norfolk Island’s reef is telling us

June 11, 2025

Day 4 of a week-long photo series from Norfolk Island, shared during the UN Ocean Conference in Nice. Today’s post spotlights a Hydnophora pilosa colony where white syndrome appeared suddenly and spread quickly, taking out around a quarter of the coral. In the months that followed, algae quietly filled the gap – a subtle but telling shift from coral to algae that’s happening across the reef.

Read More
In Environmental degradation Tags corals, coral reef, Norfolk Island, White syndrome, coral disease, UNOceanConference, UNOC2025, Water quality
Comment

Cute as buttons – Astrea curta

February 20, 2025

Astrea curta corals are ‘small, moderately plocoid [flattened], distinct, and almost circular’ . Normally grey-green in colour, you can see from the images here, ours are often beautiful rich gold, although they do vary. They have a neat growth habit and button-like corallites, which can grow in columns, spherically or flattened. Large colonies of these can form gorgeous undulating bumps.

Read More
In Corals Tags corals, Astrea curta, Norfolk Island, Emily Bay, Slaughter Bay
Comment

Slaughter Bay, Norfolk Island, March 2020

From 'Watch' to 'Warning'

January 26, 2025

Last week, the chance of coral bleaching in Norfolk Island’s inshore lagoons was raised from ‘Watch’ to ‘Warning’ and will more than likely rise to Alert levels one and two in coming weeks. So why do I worry about water quality all the time when bleaching seems inevitable these days and so the reef is probably doomed anyway? Read on to find out.

Read More
In Corals Tags corals, coral bleaching, heatwave, resilience, water quality, Norfolk Island
Comment

From little things – watching them grow

January 4, 2025

Small numbers of different fish species is not an unusual phenomenon on Norfolk Island’s reef, but it does demonstrate what a tiny, precious, coral reef ecosystem we have, when we can count individuals on one hand and watch each of them grow, like these little blackeye thicklips, a member of the wrasse family.

Read More
In Fish Tags fish, fish species, Blackeye thicklip, iNaturalist, Norfolk Island, coral reef
Comment

Emily Bay at low tide, early morning, December 2024

A year in review – 2024 on Norfolk Island’s Reef

December 27, 2024

It is five years since I began wielding a camera underwater in Norfolk Island’s lagoons and my third ‘year in review’ for this ‘Out on a swim’ blog. And what a journey it has been. At least this year I have some great news to report, but – a bit like a curate’s egg (partly bad and partly good) – there are also some downers. Find out what 2024 has meant for Norfolk Island’s reef.

Read More
In Environmental degradation Tags Norfolk Island, coral reef, corals, coral health, water quality, environment, environmental protections
Comment

The Emily Bay’s massive ‘brain’ coral, Paragoniastrea australensis, photographed on 6 July 2024

While you were sleeping ...

July 10, 2024

This massive and incredibly slow-growing Paragoniastrea australensis sits in Emily Bay on Norfolk Island and is one of our most recognisable bommies. While all looks reasonably calm during the day, at night, while you are sleeping, the surface of the coral colony seethes with millions of tiny tentacles busily reaching out to find food, while others aggressively ward off opportunistic interlopers.

Read More
In Corals Tags corals, coral reef, bommie, Emily Bay, Norfolk Island
Comment

The view across Emily Bay and Slaughter Bay’s contiguous reef at low tide. Quintal’s Passage can be seen as two parrallel lines of rocks. It runs from Emily out to sea.

Blasting a passage through the reef, Norfolk Island

April 6, 2024

We have shaped Kingston, Norfolk Island, to suit our own ends, whether it is by draining the swamp, undertaking major earthworks, or by using it for agriculture and grazing. Our interventions have placed the reef at risk. But simultaneously, the confluence of human activity and a unique natural environment have created a place of incredible significance, which deserves some special management to preserve all its facets.

Read More
In Ecosystem Tags Kingston, World Heritage Area, Norfolk Island, Water quality, Quintal's passage, coral reef, coral health, coral disease, Colonial settlement
Comment

High tide and pounding waves on Norfolk Island’s coral lagoon, southern shore, looking east towards Point Hunter

Norfolk Island reef's autopsy reports

March 3, 2024

More reports to add to a long catalogue of reports were delivered to the general public over the last few days on Norfolk Island’s water quality and reef health. Reassuringly, they all say the same thing. Our poor water quality is affecting the health of our reef. So the science must be good! So when are we going to do something about it?

Read More
In Environmental degradation Tags water quality, reports, Norfolk Island, coral health, coral disease, World Heritage Area
Comment

Green moon wrasse, Emily Bay, Norfolk Island

I only have fish eyes for you!

February 22, 2024

Do fish have eyes that move independently? Well, no, not really, but, yes, sort of, in some species, sometimes!

Read on for a brief ‘Fish eyes 101’ summary of how they work.

Read More
In Fish Tags fisheye, Fish, fish species, anatomy, Norfolk Island, Emily Bay
Comment

A territorial banded scalyfin, Parma polylepis (aatuti), Norfolk Island

Know your damsels – multispine damselfish versus banded scalyfins

February 7, 2024

The banded scalyfins and the multispine damselfish are arguably two of the most common species in Norfolk Island’s lagoons. People often confuse them, particularly the juveniles, so here are some photos to clarify which are which. Once the differences have been pointed out, you’ll never confuse them again.

Read More
In Fish species Tags fish species, fish, damselfish, aatuti, Norfolk Island
Comment

Norfolk Island’s inshore reef during low tide and at sunrise

A year in review – 2023 on Norfolk Island's reef

December 29, 2023

Sadly, the year didn’t bring any obvious improvements to Norfolk Island's reef in terms of reductions in incidences of coral disease, or runaway algal growth. And while some fish seem to have departed the scene, another species has re-established its home. Here’s a rundown of what I've been doing during the last four years of observations, and what I've seen happening on our reef in 2023.

Read More
In Ecosystem Tags 2023, Norfolk Island, coral reef, Fish, fish species, water quality, coral health, White syndrome
4 Comments

Free weed!

December 22, 2023

I couldn’t resist posting these beautiful images of floating seaweed. Enjoy!

Read More
In Biodiversity, Algae Tags seaweed, algae, Norfolk Island
Comment

Acropora coral, Norfolk Island, 14_StairwayReef, 14 November 2021

The journey from coral reef to rubble

December 16, 2023

For two years, I have stopped by and photographed this beautiful Acropora coral formation in Emily Bay on Norfolk Island. In my database for this colony, I called the folder 14_StairwayReef; 14 for the geographic location on a map, followed by my romantic name for it. Today it is just so much rubble.

Read More
In Environmental degradation Tags corals, coral reef, White syndrome, coral disease, Norfolk Island
Comment

White syndrome on a Hynophora pilosa colony, Norfolk Island, 23 November 2023

The spatiotemporal dynamics of a coral disease

December 9, 2023

A pictorial study of the spread of white syndrome, over time, in a Hynophora pilosa colony on Norfolk Island. This beautiful coral colony is in the middle of the channel that runs between the contiguous Emily and Slaughter Bays, in Norfolk Island’s inshore coral reef lagoon. It’s one of my favourite places to pause and admire the scenery, when I’m out on my swim.

Read More
In Environmental degradation Tags corals, coral reef, Norfolk Island, White syndrome, coral disease
Comment

A bubble-tip anemone, Norfolk Island

Do sea anemones hold the key to immortality?

October 17, 2023

A close relative of corals and jellyfish, sea anemones are soft-bodied animals that ensnare passing prey with their stinging tentacles. No one really knows how long they can live, but in the wild they are thought to live for more than a hundred years. They have some clever adaptations that contribute to their longevity. Maybe they can teach us their secrets for a long life!

Read More
Tags Sea anemone, Norfolk Island, marine invertabrates, immortality, telomeres
Comment

Acropora corals, Norfolk Island’s reef

Brown? Yes. Boring? Definitely not!

October 11, 2023

Norfolk Island’s reef is one of Australia’s most southerly. It isn’t showy like the Great Barrier Reef, and I often hear the comment that it is a little dowdy – boring and brown. I’m here to tell you that it is anything but.

For this little photo essay I randomly selected just a handful of my many ‘boring, brown’ coral images to demonstrate my point. I barely scratched the surface of my photo library, yet I think you will agree, the diversity is just amazing!

Read More
In Corals Tags corals, Norfolk Island, coral reef, Great Barrier Reef, Coral, biodiversity
1 Comment

Emily Bay, full moon rising, by Norfolk Island photographer Joelene Oliver

Full moon, low tides and Norfolk Island’s reef

June 2, 2023

With the low, low tides associated with a full moon, the bays on Norfolk Island are like a huge, calm swimming pool, giving us some great snorkelling opportunities. These low tides should also let us view the causeway, which will no doubt be exposed too. This post explores these opportunities as well as what the low tides mean for corals. Read more in this fact packed blog post.

Read More
In Corals Tags Norfolk Island, Full moon, Low tide, HMS Sirius, causeway, Emily Bay, Slaughter Bay, coral reef, corals, plastic, plastic pollution
2 Comments

My grandson

For the sake of our grandchildren

March 26, 2023

What will my grandson see when he is old enough to snorkel on Norfolk Island’s reef? Will there be anything left as I know it? Or will he think it is all great because of that hoary old phenomenon called ‘shifting baseline syndrome’? This record of all my photos and observations will give him some idea of what we had in our bays in the 2020s.

Read More
In Environmental degradation, Fish species Tags Environment, Environmental protection, water quality, biodiversity, grandchildren, Norfolk Island, Emily Bay
4 Comments
Older Posts →
Featured
Celebrating Biodiversity Month on Norfolk Island
Sep 7, 2025
Celebrating Biodiversity Month on Norfolk Island
Sep 7, 2025

September is Biodiversity Month – the perfect time to celebrate the astonishing variety of life on Norfolk Island’s reef. From new fish sightings to coral mosaics, every observation is a reminder of how much there is still to learn and protect.

Read more about why biodiversity matters, globally and right here in our lagoon.

Sep 7, 2025
The fate of a coral colony when it succumbs to white syndrome – four years on
Aug 24, 2025
The fate of a coral colony when it succumbs to white syndrome – four years on
Aug 24, 2025

I’ve tracked one plating Acropora coral from 2021 to 2025. In just a few weeks, white syndrome wiped it out. Nearly four years years on, it’s still smothered in algae and sea squirts, with only the tiniest hint of new growth. It’s a stark reminder: without tackling the root cause, we’re just watching the same sad story repeat itself.

Aug 24, 2025
The Candy-Striped Cleaner Keeping the Reef Healthy
Aug 17, 2025
The Candy-Striped Cleaner Keeping the Reef Healthy
Aug 17, 2025

Candy-cane stripes, long white feelers, and a reef spa on offer – the banded coral shrimp waves its antennae to advertise cleaning services to passing fish.

Aug 17, 2025
Biomimicry: How a Boxfish Caught Mercedes Benz’s Eye
Aug 10, 2025
Biomimicry: How a Boxfish Caught Mercedes Benz’s Eye
Aug 10, 2025

Meet Mr Lemonhead – our lagoon’s teeny yellow boxfish with a big design legacy. He inspired a Mercedes Benz concept car, proving how nature is full of surprises. And he shares the lagoon with other critters whose tricks have also shaped real-world inventions.

Aug 10, 2025
Patchwork Corals: How Colonies Fuse to Form Living Mosaics
Aug 3, 2025
Patchwork Corals: How Colonies Fuse to Form Living Mosaics
Aug 3, 2025

Some corals wear more than one colour for a reason. When Paragoniastrea australensis colonies fuse early in life, they form living mosaics. A beautiful reminder of coral cooperation on Norfolk Island’s reef.

Aug 3, 2025
Reef relief
Jul 28, 2025
Reef relief
Jul 28, 2025

Today, 28 July, is World Nature Conservation Day. After the dry 2024, Norfolk Island’s reef is looking healthier – a brief reprieve as less water - laden with nutrients - flowed into the lagoon. These photos show what’s possible. It’s a reminder that recovery is within reach – though renewed runoff could quickly undo the gains.

Jul 28, 2025
Emily Bay's big 'brain' coral
Jul 20, 2025
Emily Bay's big 'brain' coral
Jul 20, 2025

In Emily Bay, Norfolk Island, a single coral bommie – Paragoniastrea australensis – has stood for decades as a micro-reef, harbouring diverse marine life and local memories. Once photographed in 1988 and still thriving today, it remains a keystone of reef biodiversity and a living link between past and present.

Jul 20, 2025
Biodiversity matters
Jul 14, 2025
Biodiversity matters
Jul 14, 2025

Over five and a half years of snorkelling Norfolk’s lagoon, we’ve documented 23 fish species not previously recorded in this area. Some are local ghosts, others climate migrants. These observations help us understand and protect what makes our reef so special.

Jul 14, 2025
Poop power
Jun 17, 2025
Poop power
Jun 17, 2025

Not all poop on a reef is bad poop. In fact some kinds of poop can be a reef’s most important invisible engine. Fish poop, bird poop – even poop that gets eaten again by other fish – all of it keeps the ecosystem ticking over in a way that’s nothing short of extraordinary.

Jun 17, 2025
Glimpses of recovery: what the reef could be if we let it
Jun 13, 2025
Glimpses of recovery: what the reef could be if we let it
Jun 13, 2025

Day 6 of this photo series from Norfolk Island coincides with the final day of the UN Ocean Conference in Nice. After a week of documenting decline, today’s post offers a different view – what reef recovery can look like when conditions improve. Drought in 2024 gave the reef a break, and the results were unmistakable: healthier corals, lower disease, and more fish. This is what’s possible if we act.

Jun 13, 2025

Latest Posts

© 2025 All rights reserved.