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Norfolk Island's Reef

Discover a fragile paradise – Norfolk Island's beaches, lagoons and coral reef
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  • Out on a swim - blog
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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.

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A small school of scissortail sergeants with one interloper, an Indo-Pacific sergeant, Norfolk Island

Same, same, but different – confusing fish identities

May 25, 2023

There are a few fish species in Norfolk Island’s bays that are easily mixed up. Here’s four commonly confused pairs, with a few pointers to help you identify them.

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In Fish species Tags Fish, fish species, coral reef
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Purple velvet sea star, Leiaster leachii, as it broadcasts spawn into the water column, Norfolk Island

Casting your offspring to the currents – sea star reproduction

May 8, 2023

In May on Norfolk Island, the day after the full moon and at low tide, I witnessed an enormous Leach’s sea star, Leiaster leachi, as it broadcast its gametes into the water column. What an amazing WOW moment! And what a privilege to witness such a rare event. Here are some images and video of the action.

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In Sea stars Tags sea stars, starfish, reproduction, spawning, Leach's sea star
2 Comments

Close-up of the underside of the acropora coral colony after being toppled in a storm

The resilience of corals

May 6, 2023

On Norfolk Island’s reef, acropora coral colonies upturned in storm surges in September 2020 initially struggled to survive, but now they are now showing signs of new, healthy growth. This incredible photo is of those early days as it struggled. You can read more and see what it looks like today in my latest blog post, here.

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Crustose coralline algae, Norfolk Island

Pretty in pink – the real coral reef builders

April 8, 2023

Animal, vegetable or mineral? What are crustose coralline algae? Are they important? What role do they play on our coral reefs?

There’s a lot to learn about coralline algae. For a humble lifeform, they really pack a punch.

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In Ecosystem Tags algae, coralline algae, crustose coralline algae, coral reef, corals, sea urchin, coral recruitment
1 Comment

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.

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In Environmental degradation, Fish species Tags Environment, Environmental protection, water quality, biodiversity, grandchildren, Norfolk Island, Emily Bay
4 Comments

Black Blenny, Enchelyurus ater found in Slaughter Bay, Norfolk Island

Black Blenny - a new record for Norfolk Island

March 25, 2023

This is a copy of the Australian Fishes journal post about new fish sightings on Norfolk Island: ‘This observation [of a black blenny] highlights the power of citizen scientists working with professional ichthyologists to achieve important outcomes,’ Mark McGrouther, Senior Fellow at the Australian Museum.

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In Fish species Tags black blenny, fish species, Fish, new species, Australasian Fishes project, Australian Museum
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Doris, a week after she was taken into rehab

Doris – just one turtle?

March 24, 2023

Many of the turtles that live in Norfolk Island’s coral-reef lagoons are juveniles. In other words, they are the future of their species, and an important piece in the genetic jigsaw. Yet they seem to fall through the cracks when it comes to being protected by the EPBC Act.

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In Environmental degradation Tags Operation Doris, Turtle rescue, Green sea turtle, water quality, EPBC Act
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One of the pair of ‘sometimes’ resident snubnose darts, Norfolk Island

A pair and a spare – snubnose darts on Norfolk Island's reef

March 23, 2023

Norfolk Island’s reef is small and intimate. We can count the numbers of some species of fish on one hand, and that is how I can watch the comings and goings with interest as I swim among them. I love the stories that play out and which I get to witness – these snubnose darts (Trachinotus blochii) are a case in point.

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In Fish species Tags Snubnose dart, fish, fish species, fish behaviour
3 Comments

A sea mat on the edge of the reef where the waves break, Norfolk Island

A tale of two corals

March 22, 2023

My March focus on Norfolk Island’s reef could almost go on for a full year, there’s so much to write about. But time dictates, so I will confine my efforts to one concentrated effort of randomness! Randomness, because there has been no plan to my posts. They have evolved as the month has progressed. Today I highlight two very different corals commonly seen, but not necessarily common.

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In Corals Tags corals, coral reef, soft coral, hard coral, water quality, biodiversity, IUCN Red List, Vulnerable
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Bubbles of oxygen forming on algae, photobombed by a tiny sea slug, sp, Elysia

Bubble and fizz – a quick guide to coral reef chemistry

March 21, 2023

March is often the warmest month on Norfolk Island’s reef, so it's no surprise that the algae are very busily photosynthesising and flourishing. Yesterday, I noticed that the algae had created a thick carpet of bubbles. As I swam my face was gently brushed by thousands of tingling bubbles, fizzing to the surface. It was quite a sight. And a rather weird sensation. So what is going on here?

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In Environmental degradation Tags Algae, coral reef, corals, photosynthesis, reef chemistry, water quality
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Emily Bay, Norfolk Island, #thecoloursarereal!

Beneath the waves in Emily Bay, Norfolk Island

March 20, 2023

Looking across Emily Bay, do you wonder what is beneath the waves in there? Although this is not strictly part of Norfolk Island’s reef, it is part of one continuous ecosystem; therefore, in today’s March focus on Norfolk Island’s reef I thought it was worth showing you what you can see at your feet as you wade into the shallows.

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In Ecosystem Tags Emily Bay, Snorkelling, Fish, fish species, ecosystem
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Stunning Emily Bay, Norfolk Island.

Tiptoeing through the government silos

March 19, 2023

In the 1960s we had reports voicing concerns around water quality, but nothing was done. When the Commonwealth of Australia’s EPBC Act came into force in 1999, nothing was done. Surely it is high time the issues of failing and inadequate infrastructure, deficient Norfolk Island laws and unsatisfactory protections were fixed once and for all?

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In Environmental degradation Tags Environment, Environmental protection, government, government policy, environmental protections, water quality, sewerage, coral reef, endemic, threatened species, biodiversity
2 Comments

Acropora coral overgrown with algae, Norfolk Island

We can't say we weren't warned

March 18, 2023

Today’s post for the March focus on Norfolk Island’s reef is a letter. Just that, and nothing more. The authors of this letter have very generously given me permission to reproduce it here. In it, Dr Kellie Pendoley and Dr Martin Goldsmith warn us about the future of Emily Bay. Written nearly eight years ago they give the coral reef habitat five to ten years before it is gone as we know it.

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In Environmental degradation Tags Environment, coral reef, corals, Environmental protection
2 Comments

Threadfin butterflyfish, Chaetodon auriga, Norfolk Island

Butterfly, flutterbyfish

March 17, 2023

Butterflyfish are flighty, brightly coloured and beautifully conspicuous on our coral reef in their bright yellows and oranges, white and black livery. On Norfolk Island we regularly see fourteen species, just a small portion of the more than 100 species, globally. Large numbers of butterflyfish are a good sign of a healthy reef.

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In Fish species Tags butterflyfish, Fish, fish species, biodiversity, coral reef
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Yellowstripe goatfish, Mulloidichthys flavolineatus

By the hair of a goatfish's chinny chin chin!

March 16, 2023

If you go for a snorkel on Norfolk Island’s reef, one family of fish that you are bound to see is members of the goatfish family. I have seen have six different species inside our lagoons. You can see them all here.

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In Fish species Tags goatfish, Fish, fish species
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Adult female elegant wrasse, Norfolk Island

Ageing elegantly – the elegant wrasse's lifecycle

March 15, 2023

It’s always fascinating to see how fish change in appearance as they mature. Today’s blog post features the elegant wrasse, Anampses elegans. But not only do they change how they look, they also change how they socialise and move about the reef.

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In Fish species Tags fish species, Fish, Elegant wrasse
2 Comments

Norfolk Island blenny, Parablennius serratolineatus

Norfolk Island's endemics on record

March 14, 2023

It is fascinating to me that, in terms of biodiversity, there is still a slight feel of the frontier to Norfolk Island. So remote and isolated from any other land mass, it stands to reason that we have some different species that are found only here. On such is the Norfolk Island blenny.

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In Biodiversity Tags fish species, Fish, endemic, Norfolk Island, Norfolk Island blenny
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A bluestreak cleaner wrasse (Labroides dimidiatus) cleaning a coral sea gregory (Stegastes gascoynei)

One small fish for one big job

March 13, 2023

Bluestreak cleaner wrasse, Labroides dimidiatus, are important critters on our coral reefs. These fish offer a swim-through full-body maintenance shop for other fish species – their clients – nibbling away dead skin and any nasty ectoparasites that might be living on their clients. There’s a lot to be learned about a reef from watching these busy little fish.

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In Fish species Tags Bluestreak cleaner wrasse, cleaning stations, Fish, reef fish, fish species, parasites, Fish behaviour
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Low tide at Cemetery Bay, Norfolk Island

A rare gem – Cemetery Bay, Norfolk Island

March 12, 2023

No focus on Norfolk Island’s reef would be complete without a look at Cemetery Bay. It’s worth strolling along this beautiful beach at low tide. It is the island’s dog beach, so you will see plenty of locals out walking here, but better still is what you can see in the water – healthy corals happily growing right up to the beach.

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In Corals Tags Cemetery Bay, corals, Coral, coral reef, rockpools
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Just some of our beautiful corals on Norfolk Island

A boring, brown reef?

March 11, 2023

People say that Norfolk Island’s reef is rather boring and brown when compared to the Great Barrier Reef. While it may not be as colourful, I think you have to agree that it is anything but boring brown!

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In Corals Tags corals, coral reef, Coral, Great Barrier Reef, Norfolk Island, biodiversity
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Featured
From ridge to reef: unpicking the Waterway and Wetland Strategy
July 24, 2026
From ridge to reef: unpicking the Waterway and Wetland Strategy
July 24, 2026

Norfolk Island’s draft Waterway and Wetland Strategy will guide work for the next ten years. I support its intent, but it needs to be clear, practical and measurable – joining the dots from ridge to reef so we know whether public money is improving water quality and helping the reef.

July 24, 2026
Reef reality in pictures
July 13, 2026
Reef reality in pictures
July 13, 2026

Let the pictures do the talking. This is the reality on Norfolk Island’s reef today, laid out in a two-minute video.

July 13, 2026
The red seaweed behind low-methane beef
June 28, 2026
The red seaweed behind low-methane beef
June 28, 2026

A small red seaweed on Norfolk’s reef has become part of a much bigger story. Asparagopsis taxiformis can look like a delicate red feather duster or, at another stage of its life cycle, like a tiny cottony pom-pom. It is beautiful, easily overlooked, and now being used in the cattle industry to help reduce methane emissions. This post looks at the reef oddity behind the low-methane beef story – and why repeated local observation can be more useful than it first appears.

June 28, 2026
From coral scar to aatuti farm
June 20, 2026
From coral scar to aatuti farm
June 20, 2026

Aatuti are bold little algae farmers, but how does one of their farms begin? Over the past year, I have been following several coral patches as small white scars became algal footholds, then larger defended patches. I still cannot say what caused the first wounds, but the photo sequences show something fascinating: on a reef where algae is already gaining ground, even tiny changes on the coral surface can become part of a much bigger story.

June 20, 2026
Norfolk’s water quality – when action is reported as outcome
June 15, 2026
Norfolk’s water quality – when action is reported as outcome
June 15, 2026

A recent Australian Government media release presents investment, monitoring and catchment works as progress on Norfolk Island’s water quality. Some of that work is useful, and some of it was badly needed. But activity is not the same as proven improvement. This post looks at Kingston sewerage, wetlands, cattle, acid sulfate soils, groundwater and reef health, and asks whether Emily Bay and Slaughter Bay are actually being better protected.

June 15, 2026
How surgeonfishes got their name
June 14, 2026
How surgeonfishes got their name
June 14, 2026

Surgeonfish are named for the sharp little scalpels near their tails, but on Norfolk’s reef their more useful work happens at the other end. Pencil surgeonfish, bluespine unicornfish and their relatives help browse algae across the reef – a small daily job that becomes very valuable on an algae-rich lagoon reef like ours.

June 14, 2026
A shrimp storm
May 28, 2026
A shrimp storm
May 28, 2026

While setting my research cams last week, I swam into what looked like an underwater snowstorm. It appeared to be the aftermath of a mass moulting event, with large numbers of tiny, translucent shrimp-like exoskeletons drifting together near the surface.

May 28, 2026
Kingston dredging: what happens when a reef does not fit the framework
May 28, 2026
Kingston dredging: what happens when a reef does not fit the framework
May 28, 2026

This correspondence with DCCEEW is about more than one dredging proposal. It is about what happens when an ecologically distinctive place is assessed through standard tools that do not always make its most important values easy to see. I am publishing it here because that is something we need to be aware of, both on Norfolk Island and more broadly in Australia.

May 28, 2026
Kingston dredging: the project advances, the questions remain
May 24, 2026
Kingston dredging: the project advances, the questions remain
May 24, 2026

Kingston dredging is edging closer, and the paper trail is growing. This post brings together earlier correspondence with the Department and the latest media release so readers can see what has been asked, what has been answered, and what still remains unclear about the project, its rationale, and the protections proposed for the reef.

May 24, 2026
The lime-green coral in Slaughter Bay – a 40-year paper trail
May 17, 2026
The lime-green coral in Slaughter Bay – a 40-year paper trail
May 17, 2026

Green Mountain – the name I give this coral in my database – is a coral I’ve photographed for years as I swim past. Then I found its backstory in the Norfolk Island National Parks archives: a rough map, reused paper, a note in the margin – ‘still thriving’. That’s how baselines begin.

May 17, 2026

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